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Ensure a strong level of
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Select lifecycle-centric manufacturers who minimize the negative
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Vol. 57, Number 5
JUNE 2020
16 | How to maintain hospital
functionality during construction
Referring to NFPA 99 helps engineers minimize
impacts in hospital and health care projects.
Replacing, extending or removing existing systems
will result in outages; here are tips on how to avoid
22 | How to apply NFPA 99 in the
design of health care facilities
ON THE COVER: A hybrid operating room, incorporating sophisticated imaging technology into the operating
theater, began operations in a major urban hospital in the
southwestern United States last year. Courtesy: ShauLin
Hon, Slyworks Photography, Johnston, LLC
5 | Viewpoint
Will a pandemic change building codes?
6 | Infection control technologies
for building design
Building design and operations need to consider infection control technologies in the wake of the
COVID-19 pandemic
10 | Basics of NFPA 99 changes
for hospital design
How engineers should navigate the changes to the
2018 edition of NFPA 99
Examine three areas of NFPA 99 that are often
discussed during the design and construction of
a health care facility
28 | How to apply NFPA 99 to medical
gas, telecommunication systems
Engineers should understand NFPA 99 — along
with other guidelines and codes — when designing
health care facilities
36 | Strategies to
improve chiller
plant performance,
Learn how to design chilled
water systems that meet the
thermal comfort demands
and achieve operational and
energy efficiencies
42 | Green, zero energy and energyefficient buildings
How do you design an energy-efficient building?
Learn about codes and standards, building energy
terminology and design goals
48 | MEP Roundtable
How is COVID-19 affecting retail, restaurants?
CONSULTING-SPECIFYING ENGINEER (ISSN 0892-5046, Vol. 57, No. 5, GST #123397457) is published 11x per year, monthly except in February, by CFE Media, LLC, 3010 Highland Parkway,
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hereby disclaims any liability to any person for any loss or damage caused by errors or omissions in the material contained herein, regardless of whether such errors result from negligence, accident or any other cause whatsoever.
consulting-specifying engineer
June 2020
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Principal, Metro CD Engineering LLC, Columbus, Ohio
Senior Electrical Engineer, Johnston, LLC, Houston
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Brentwood, Tenn.
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Will a pandemic change
building codes?
COVID-19 is forcing engineers to think differently
about a building’s engineered systems
he focus of Consulting-Speci- functions during construction and other
fying Engineer’s June coverage pertinent issues, let’s look ahead to what
was thrown out the window will happen in the future.
a couple of months ago as the
Hospitals are complex structures
coronavirus pandemic swept across the with stringent codes already, so codes
world, hitting the United States especial- and standards may not need to shift as
ly hard. While energy efficiency, chilled dramatically as they would for other
water and other technical topbuildings. Based on converics are important to engineers
sations I’m having right now,
and building professionals,
other building types may see
a few other things moved up
extreme changes in the next
the priority list.
code cycle. Code cycles typHospitals and health care
ically are on a three-year
facilities bubble to the top
timeline, so knee-jerk reacof nearly every conversations likely will not happen.
tion I’ve had with engineers
Ongoing research and new
Amara Rozgus,
lately. Whether it’s an artitechnology will drive the
cle about modifying convendiscussions — and possibly
tion centers and stadiums to
some arguments.
treat COVID-19 patients en masse or a
Major employers already have told
Q&A about how engineering firms are their workforce that employees will
changing their workforce to be fully not be returning to the office any time
virtual, the topic of the coronavirus soon, and some will never return to
takes over the discussion.
an office. This shift in how business
Some firms and their hospital is done may change the face of engiexperts are just now coming up for air, neering; according to research done by
after months of assisting clients with Consulting-Specifying Engineer, office
pandemic-related design challenges. buildings are the No. 1 building type
While the pressurization needs of a hos- engineers design or retrofit.
pital are not new to mechanical engiHerd immunity and a vaccination
neers, the immediate need of modifying will allow life to return to pseudo-norexisting buildings or designing isolation mal, however that will take time, so
tents impressed upon me the dedication K-12 and higher education adminisof these building experts. The urgency trators will have to consider their stuof the matter and the commitment of dents’ safety in the short term. This
consultants, manufacturers, contrac- demands a shift for some schools, such
tors and others creating these facilities as renovations in large auditoriums or
showed the world how building experts new technologies added to enhance
can really shine in tough situations.
indoor air quality.
It also put a spotlight on the issue of
Until then, please share your knowlcodes and standards, such as NFPA 99: edge and understanding of products and
Health Care Facilities Code. While sev- systems that, with verified information,
eral articles in June focus on the updates can improve buildings now and change
to NFPA 99, ensuring a hospital still codes or standards in the future. cse
Vice President, WSP USA, Orlando, Fla.
Electrical Engineer, McGuire Engineers Inc., Chicago
consulting-specifying engineer
June 2020
By Dustin Schafer, Henderson Engineers, Kansas City
Infection control
for building design
Building design and operations need to consider infection control
technologies in the wake of the COVID-19 pandemic
he recent spread of the pandemic coronavirus (COVID-19) has brought several new questions to the forefront with
respect to the design and operation of
the buildings in which we spend much
of our time, specifically when it comes to infection
Many of us are asking “how clean are our buildings, really?” and, “what can be done to control the
spread of viruses in a high-density space?” Topics
like surface cleaning and air purification practices
that were once the sole domain of the health care
industry are now top of mind in discussions about
workplaces, restaurants, education facilities, retail
spaces and grocery stores. With this renewed interest comes a new market for many high-quality sanitation and air filtration products — but separating
the valid claims from the noise can be difficult.
In this article, we’ve summarized some of the
more effective existing technologies for infection
control in buildings. We’ll briefly discuss how each
works along with some of their risks and benefits.
There’s a variety of technologies that can play a role
in reducing the potential for the spread of infection
within a building and as your partner, we at Henderson stand ready to help you select the correct
technology to suit your specific application.
HEPA filtration
A standard air high-efficiency particulate air
filter looks and acts much like any air filter in that
it captures but does not kill contaminants. The
HEPA designation means that the filter assembly was designed and tested to capture 99.7% of
particles in the air passing through it that are 0.3
microns in size. The 0.3-micron size represents
Figure 1: Highefficiency particulate air filters can
be very effective
in capturing and
removing viruses
from air streams, as
long as they pass
through the filter.
Courtesy: Lance
Schmittling/Henderson Engineers
June 2020
consulting-specifying engineer
Figure 2: Bipolar
ionization generators
create positively and
negatively charged
oxygen ions, which
bind to contaminants in the indoor
air. Courtesy: Lance
Schmittling/Henderson Engineers
the most difficult particle size to capture so the
99.7% capture rate actually represents the worstcase efficiency of the filter. For particles that are
larger or smaller than 0.3 microns, the capture rate
Since most viruses are less than 0.3 microns,
HEPA filters can be very effective in capturing and
removing viruses from air streams, as long as they
pass through the filter. However, because HEPA
filters are typically installed in the ductwork and
therefore must rely on the room airflow patterns
to carry contaminants to the filter, small particles
like viruses circulate in the room for an extended
time before eventually making their way to the filter for capture. In general, while highly effective
and reliable, an in-duct HEPA filter is more appropriate in preventing cross contamination between
spaces than it is in guaranteeing removal of contaminants from a given space.
• Proven technology, no moving parts, easily
• Effective at particle entrapment.
• Effective at protecting space-to-space
• Only captures particles from the ducted
air — not within the space.
While highly effective and reliable,
an in-duct HEPA filter is more appropriate
in preventing cross contamination
between spaces.
Bipolar ionization
Bipolar ionization generators create positively and
negatively charged oxygen ions which bind to contaminants in the indoor air, either causing them to
drop out of circulation in the room or to be captured
by a mechanical filter within an air handling unit.
When properly installed, operated and maintained,
bipolar ionization systems can reduce dust and mold,
capture odors, reduce volatile organic compounds
and reduce viruses and bacteria in the air.
Ions generated by these devices typically have a
relatively short life span, so it’s important to regularly
pass room air over the ion generator to ensure sufficient contact. Typically, bipolar ionization generators are installed in the ductwork or directly in the
air handling unit, but recirculating room units are
available through some manufacturers. With any
ionization product, it is important to investigate the
potential to create ozone, which has proven negative
effects on human health, as a byproduct of operation.
• Some increase in energy usage due to increase
air pressure drop and motor work.
• Little additional pressure drop added to
• Increased maintenance due to filter
• Requires no re-engineering of existing
HVAC system.
consulting-specifying engineer
June 2020
• Emitter wear and calibration requirements.
• Only captures particles from the ducted
air — not within the space.
• Potential to create ozone byproduct.
Active particle control devices
Active particle control devices perform similarly to a bipolar ionization generator, with one
important distinction. Rather than charging oxygen molecules to act as a contaminant attraction
device, active particle control devices charge the
contaminant particle itself, causing it to aggregate
with other smaller particles to form a larger conglomerate particle that can be captured by a downstream air filter. These devices effectively increase
the filtration ability of the downstream filter by
grouping smaller particles together.
• Little additional pressure drop added to
• Requires no re-engineering of existing
HVAC system.
• Emitter wear and calibration requirements.
• Only captures particles from the ducted
air — not within the space.
• Potential to create ozone byproduct.
Pathogens and infectious droplets travel further
in dry air, especially when the relative humidity is
below 40%, which is partly why we tend to see more
illness in the drier winter months. By maintaining indoor relative humidity between 40% to 60%,
building operators can reduce the risk of spreading airborne infectious diseases in their facilities. In
most climate zones across the U.S., maintaining this
range requires not only the dehumidification technologies that are traditionally designed in HVAC
systems, but also the less common technologies that
add humidification to spaces.
• Creates a less hospitable building climate
for viruses.
• Reduces static.
• Increases occupant comfort in winter.
• Does not capture or kill pathogens.
• Consumes water for humidification.
• Can add significant cost to the system
Ultraviolet sterilization
Anyone who has ever gotten a sunburn is
familiar with UV light’s ability to degrade organic materials. Given the proper contact time and
intensity, UV light can inactivate viruses and bacteria — rendering them harmless. UV lights can
Figure 3: Ultraviolet light, with
a wavelength
between 200 and
280 nanometers,
has proven to be
the most effective
for infection control while inflicting
minimal damage to
humans or other
mammals present
in the space. Courtesy: Lance Schmittling/Henderson
June 2020
consulting-specifying engineer
be installed in an air handling unit or even directly
in the space itself, but the light must directly contact the pathogen in order to be effective. There is
no travel distance or “conditioning” of the air that
takes place.
UV light, with a wavelength between 200 to
280 nanometers has proven to be the most effective for infection control while inflicting minimal
damage to human skin or other mammals present
in the space. There are many novel applications of
“in-room” UV sterilizers specific to almost every
application, including stationary lights or portable devices mounted on robots for off hour surface
• Can destroy microorganisms like mold,
bacteria and germs.
• Applicable in a room-based or air handlerbased setting.
• Does not filter contaminants from the space
Vaporized hydrogen
peroxide injections
On the more aggressive end of the spectrum
for room sterilization technologies is the injection of vaporized hydrogen peroxide directly into
the space. Hydrogen peroxide is a potent sterilizing agent that has been used to decontaminate
buildings infected with a range of biological contaminants from anthrax spores to exotic viruses.
The process is performed by injecting vaporized
hydrogen peroxide into a sealed vacant space and
is usually used more as an intentional sterilization
procedure rather than a routine part of normal
building operation.
• Highly effective at destroying microorganisms
like mold, bacteria and germs
Elevated body temperature detection
One way to control the risk of infection in
your facility is by detecting potentially contagious
patrons before (or as) they walk through your
doors. To do this, one widely discussed solution is
the application of thermal imaging to detect elevated body temperatures. These systems work by using
infrared radiation to evaluate temperature differences on the surfaces of the skin or other materials. A variety of devices exist with this technology
including ceiling/wall-mounted cameras, handheld
thermal imagers or devices integrated into existing
security or building automation systems.
• Passive devices that can be integrated into
existing systems.
• Real-time feedback on potential infected
occupant entering the building.
• Potentially slows down building entry which
could complicate social distancing.
• Can be expensive to administer at multiple
access points.
As a society, our awareness of how quickly potential pathogens can spread has increased
dramatically in just the span of a few months. We
understand the importance of human health and
furthermore, we understand that our economic
livelihood as individuals, as a nation and even as a
world depends greatly on our ability to move about
freely without concern for the spread of infection.
While safety and comfort have always been priorities for those who design and operate the buildings in which we live, work and play, the COVID-19
pandemic has added another factor to be considered. However, with the proper application of active
infection control technologies like those listed here,
we are confident we can meet this challenge head
on to help us all get back out in our communities as
quickly as is safely possible. cse
• Not practical for wide disinfection of occupied/finished spaces like office buildings or
Dustin Schafer is director of engineering and senior
vice president at Henderson Engineers. This article
originally appeared on Henderson Engineers’ website.
Henderson Engineers is a CFE Media content partner.
• Room temperature and humidity require
tight controls for efficacy.
M More
• Requires pre-cleaning of all surfaces before
Find more resources at www.csemag.com, including:
• Weekly newsletter: www.csemag.com/
consulting-specifying engineer
June 2020
By Tom Divine, PE, Johnston, LLC, Houston
Basics of NFPA 99 changes
for hospital design
How engineers should navigate the changes to the 2018 edition of NFPA 99
he 2018 edition of NFPA 99: Health Care
Facilities Code, continues to build on the
risk-based approach to facility design
that had been established in the 2012
edition. This article addresses changes to
the 2018 edition that affect the design of mechanical, electrical, plumbing and fire protection systems
in health care facilities, specifically covering chapters
in the code that directly affect those disciplines.
Chapter 4 is also included to capture its clarification of responsibility for risk assessments, which has from time to time
been presumed to fall to the design
team. New Chapter 15, Dental Gas
and Vacuum Systems, is not covered
• Learn the details of specific
changes to NFPA 99-2018.
here, due its limited applicability to
health care facility design.
• Understand the general impact
of changes to requirements for
Major changes include requiregas and vacuum systems .
ments for oxygen concentrators and
• Know the limited impact of
corrugated metal tubing in Chapter
the sweeping changes to the
5, Gas and Vacuum Systems, and the
chapter covering electrical
reorganization of Chapter 6, Electrisystems.
cal Systems.
Minor changes appear in chapters dedicated to
plumbing, heating, ventilation and air conditioning
and fire protection.
Chapter 4: Fundamentals
NFPA 99 Chapter 4 was introduced in the 2012
edition, where it presented the transition from
occupancy-based to risk-based requirements.
Chapter 4 mandated risk assessments and defined
risk categories for activities, systems and equipment
based on the outcomes of those assessments. In the
2015 edition, Section stated that the “governing body” held the responsibility for determining the risk categories of patient care spaces.
That nomenclature resulted in a level of confusion among users of the code. Some interpreted it
to mean that local authority having jurisdiction or
state accreditation boards were responsible for producing those risk assessments. The intent of the
code is that the governing body of the health care
June 2020
consulting-specifying engineer
facility itself has that responsibility. That intent is
clarified in new Section 4.2.1, which requires that
the “health care facility’s governing body shall
establish the processes and operations that are
planned for the health care facility.” New Section calls for risk assessment to be provided to
the AHJ for its review where the AHJ requires it.
Chapter 5: Gas and Vacuum Systems
NFPA 99 Section relaxes the
requirement for exits in an outdoor central supply system or storage of positive-pressure gases,
requiring two exits only when the area of the
installation exceeds 200 square feet. The 2015 edition had required two exits regardless of the area,
leading to convoluted designs for small facilities.
Note, though, that still requires two
exits for cryogenic for bulk cryogenic liquid systems, regardless of size.
Section and (10) clarify requirements for heating of central supply systems and
positive-pressure gas storage locations. The previous edition called for heating by indirect means,
without any quantitative description of requirements. The 2018 edition prohibits fuel-fired equipment in the gas source or storage room and restricts
the temperature of the heating element to 266°F.
Steam, hot water and electric heating systems
meeting this requirement are permissible in this
Section requires that unconnected gas
cylinders be stored in locations that comply with, covering design and construction of storage locations, and with, covering ventilation for those locations. Section, Storage,
which encompasses, is cited in as
applying to both new and existing systems. Under
the 2015 edition of NFPA 99, this requirement
would apply to existing systems. The 2018 edition
adds text stating that approved existing systems
shall be permitted to continue in service, abrogating this specific requirement for existing storage
Figure 1: A hybrid operating room, incorporating sophisticated imaging technology into the operating theater, began
operations in a major urban hospital in the southwestern United States last year. This room was part of a larger renovation, encompassing five new operating rooms, two hybrid operating rooms, blood bank, pharmacy, central sterile processing unit, post-operative care and an oral surgical clinic. Courtesy: ShauLin Hon, Slyworks Photography, Johnston, LLC
Requirements for oxygen concentrators are new
to the 2018 edition. Oxygen concentrators have
not been addressed in previous editions of NFPA
99, though they’ve been covered in standards used
outside the United States for several years. Oxygen
concentrators take on a special importance in areas
that are not easily serviced by oxygen suppliers.
The specific requirements for oxygen concentrators
are too numerous and complex to allow a detailed
description here, so references to the code itself are
provided instead.
Requirements for concentrator units appear in
Section Additional requirements for
oxygen central supply systems using concentrators
are stated in Master alarm requirements
for central supply systems using concentrators are
found in Section describes
requirements for operating controls and
for operating alarms and local signals. NFPA 99
Section covers requirements for local
alarms when concentrators are part of the central
supply system.
New requirements for inlet filtration of central supply systems for vacuum appear in Section The intent of vacuum filtration is to
restrict the movement of particulates in the vacuum
Figure 2: Copper
gas piping is shown
in the ceiling space
of a hospital. Courtesy: Johnston, LLC
system and thereby provide a measure of protection for persons maintaining or inspecting vacuum
equipment. While the code requires that the filters
shall be installed on the patient side of the vacuum
producer — the vacuum pump — it doesn’t state
whether the filters should be upstream or downstream of the receiver, leaving this decision to the
system designer.
At least two filter units or bundles are required,
with isolation to allow one filter to serve the system
while the other is replaced. Filter efficiency is specified at “0.03 micron and 99.97% HEPA,” though
“0.03 micron” may well be a typographical error,
consulting-specifying engineer
June 2020
Figure 3: A
2-megawatt generator was installed
indoors at a medical facility. Courtesy: Johnston, LLC
The changes to NFPA 99 Chapter 6
are almost exclusively editorial, with very
little in the way of substantive changes
to requirements.
intended to be “0.3 micron.” Also required are a
means to allow the user to observe accumulations
of liquids — typically a sight glass — and a petcock
to relieve vacuum in the filter canister.
A new section was added to Annex A: Explanatory Material, connected to Section,
clarifying that the intent of the requirement that
a zone valve be “readily operable from a standing position,” is that it be operable by a person of
average height, standing in front of the valve, with
both feet on the floor. It appears that some operators may have tried to certify zone valves mounted
high on the wall, under the theory that an operator
standing on a ladder or stepstool was “in a standing position.”
New Section permits corrugated
medical tubing for positive-pressure Category 1
systems, in addition to hard-drawn seamless copper
Type L and Type K. The tubing must be listed and
the listing must include testing to demonstrate that
CMT systems can be consistently gas-purged with
results comparable to hard-drawn copper medical
gas tubing.
June 2020
The CMT must also meet an array of criteria
specified in, and
Installation restrictions for CMT appear in new
Sections and Turns, offsets and
direction changes in CMT systems shall be implemented with fittings, or by tubing bends no tighter than the tubing’s listed minimum bend radius.
Mechanically formed, drilled and extruded teebranch connections are prohibited in CMT systems.
A number of errata have been identified in
Chapter 5 and its corresponding entries in Annex
A: Explanatory Material. All of those errata are
erroneous or outdated references to other locations
in the code.
Chapter 6: Electrical Systems
NFPA 99 Chapter 6 was reorganized. The changes to Chapter 6 are almost exclusively editorial,
with very little in the way of substantive changes
to requirements. The intent of the reorganization
was to make Chapter 6 more logical and usable.
The numbering system was simplified, with fewer
subheadings. Some portions were relocated to place
them with related requirements. Chapter 6 had
accumulated a number of duplications and many
of those were removed. Related requirements were
brought together. Other goals of the reorganization were to bring the chapter into closer compliance with NFPA 99 style guidelines and to change
the flow to a more risk-based approach.
One of the consequences of the extensive editorial reorganization is the difficulty of identifying
substantive revisions in any meaningful way. Nearwww.csemag.com
ly all of the text has been altered, but the requirements remain almost entirely unchanged. The
nature and extent of the revisions don’t allow for
comparing sections in the previous edition to identify changes. Consequently, every section in the
2018 edition’s Chapter 6 is marked as revised. Due
to the difficulty of identifying substantive revisions
in the code and the small number of changes, an
effort is made here to describe all of the substantive changes to Chapter 6. Nevertheless, this list it
may be incomplete.
Section shows requirements for receptacles in “clinical laboratories.” A new section in
Annex A: Explanatory Material defines a clinical
laboratory as “a space where diagnostic tests are
performed as part of patient care.” The corresponding section in NFPA 99-2015,, appeared to
apply to laboratories in general. The revision clarifies that this section applies only to clinical laboratories and not, for example, research laboratories
that may be house in the health care facility. The
receptacle requirements are unchanged.
The 2012 and 2015 editions of NFPA 99 both
declared in Section that “operating
rooms shall be considered to be a wet procedure
location, unless a risk assessment conducted by the
health care governing body determines otherwise.”
This default designation as wet procedure locations
triggered requirements for special electric shock
protection, typically in the form of isolated power
systems or ground fault circuit interrupters.
In the 2018 edition, that requirement survives
unchanged as Section New text in Section clarifies that special electric shock protection is not required in the operating room if a risk
assessment determines that the room is not a wet
procedure location.
Section 6.5.2 requires that Category 2 spaces served by either a Type 1 or a Type 2 essential
electrical system be served from a transfer switch,
and at least one other circuit that is served from
either the normal power distribution system or
from a different transfer switch. This requirement
is new to the 2018 edition. Previous editions contained a similar prescription for Category 1 spaces, requiring circuits specifically from the critical
branch and from either normal or from a separate
critical branch transfer switch; however, no such
requirement existed in the previous editions for
Category 2 spaces.
Category 2 spaces may be served from either
a Type 1 or a Type 2 EES, as provided in 6.5.1. A
Type 2 EES has only two branches and does not
have a critical branch, as described in
Therefore, the requirement for Category 2 spaces
does not reference a specific branch. The requirements for the life safety branch sharply limit the
types of loads that it may serve, so this requirewww.csemag.com
Figure 4: A zone
valve box is shown
installed in a hospital corridor. Courtesy: Johnston, LLC
ment will nearly always be met with circuits from
the equipment branch.
Fuel cell systems were permitted as an alternate source for an EES in the 2015 edition, in
Section, provided that they could energize load within 10 seconds of an outage, had at
least one redundant unit, had an adequate on-site
fuel supply and a continuing source of fuel and
were backed up with a portable generator connection. In practice, fuel cells are rarely appropriate for health care use due to their generally
small capacities, their inability to meet the 10-second rule from a cold start and the difficulty of
storing adequate amounts of their gaseous fuels.
NFPA 99-2018 also permits fuel cells and adds the
requirement that they be listed for emergency use,
in Section
The 2015 edition, in Section, requires
that main circuit breakers and feeder circuit breakers be inspected annually and periodically exercised in a program established in accordance with
manufacturer’s recommendations. This same
requirement appears in the 2018 edition in Section, along with the additional requirement that those breakers also be maintained in
accordance with manufacturer’s instructions and
industry standards. This requirement is specifically
noted as applicable to both new and existing facilities, as part of 6.7.4, in Section 6.1.3(12)
Chapter 8: Plumbing
NFPA 99-2018 Chapter 8 has only one revision.
Section 8.3.6 requires that special water systems
comply with FGI guidelines or with, “the appliconsulting-specifying engineer
June 2020
Figure 5: Gas outlets were installed in the headwall of a patient bed
location. Courtesy: Johnston, LLC
cable ANSI-reviewed standard.” The 2015 edition was less specific, calling for compliance with
Facility Guidelines Institute guidelines or “other
appropriate publicly reviewed nationally published
Chapter 9: HVAC
Chapter 9 shows limited revisions, with few substantive changes.
In the 2015 edition, Section requires
that exhaust fans be connected to the essential electrical system. NFAP 99-2018, using the same section
number, adds a requirement that a risk assessment
be conducted for installations without an essential
system to determine whether continuous operation
must be provided by some alternate means.
Section revises requirements for medical
plume evacuation. Three alternative methods of evacuation are provided in the 2015 edition: a dedicated
exhaust to discharging outside the building, high-efficiency particulate air filtering and direct connection to
a return or exhaust duct and sterilization by chemical
and thermal and return to the space.
The 2018 edition revises each of those methods. For dedicated exhaust systems to the outdoors,
exhaust must be 25 feet from building openings or
places of assembly, at an elevation different from air
intakes, in a location where prevailing conditions
won’t divert the exhaust to occupied areas or prevent dispersion. For connection to existing return
or exhaust systems with HEPA filtering, the 2018
edition adds a requirement for gas phase filtration.
In the third alternative, the requirement for sterilization is replaced with a point of use smoke evacuator for air cleaning.
Chapter 16: Features of Fire Protection
Features of Fire Protection appeared as Chapter 15 in the 2012 and 2015 editions. It was renumbered as Chapter 16 to make way for the new
Chapter 15, Dental Gas and Vacuum Systems.
June 2020
consulting-specifying engineer
The most interesting change to Chapter 16 in
the 2018 edition is Section, which allows
for omission of fire alarm notification appliances, both audible and visual, in patient care spaces,
when a risk assessment indicates that their presence
may adversely affect patient care and an alternative means of notification is provided. This section
was numbered in the 2015 edition, which
allowed visual notification appliances to be used in
lieu of audible appliances in critical care areas.
The new section is much broader; it allows
patient care spaces to be occupied without visual or
audible fire alarm notification appliances, provided
that a risk assessment warrants it and some means
of alternative notification is provided.
It has long been the practice in hospital design
to omit notification appliances from patient sleeping rooms, with good reason. For higher acuity patients, the decision of whether to evacuate
will likely depend as much on the patient’s medical needs as on any physical threat. It would seem
unwise to expose the patient or visiting family, to
signals that would initiate mandatory evacuation in
any other milieu.
However, until now, there have been no references to this practice in any of the codes. There is
often quite a bit of confusion in the permit process,
as the fire marshal tries to reconcile the needs of
patients with the black-letter requirements of the
codes. While few local jurisdictions enforce NFPA
99, this provision gives design and construction
teams a leg to stand on in discussions with local
authorities about notification appliances in patient
sleeping rooms.
Four new sections covering portable fire extinguishers have been added to Chapter 16. These sections describe requirements for fire extinguishers
in specialty spaces. In MRI rooms and associated
spaces, extinguishers must be nonferrous, to avoid
unwanted or even catastrophic, interaction with
strong magnetic fields ( In kitchens and
other cooking areas, where there is, “a potential for
fires involving combustible cooking media,” Class K
extinguishers, specifically designed for fires in animal or vegetable fats, are required (
Clean agent fire extinguishers are required in telecommunications entrance and equipment rooms to
avoid damage to electronic equipment (
Clean agent or water mist extinguishers are required
in operating rooms ( It is worth noting that
carbon dioxide extinguishers comply with definition of clean agent as defined in NFPA 10: Standard
for Portable Fire Extinguishers and that definition is
copied into NFPA 99 (3.3.23). cse
Tom Divine is a senior electrical engineer at Johnston, LLC. He is a member of the Consulting-Specifying Engineer editorial advisory board.
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By Richard Vedvik, PE, IMEG Corp., Rock Island, Ill.
How to maintain
hospital functionality
during construction
Referring to NFPA 99 helps engineers minimize impacts in hospital and
health care projects. Replacing, extending or removing existing systems will
result in outages; here are tips on how to avoid problems
s hospitals and health care facilities
react to the federal adoption of the
2018 editions of NFPA 99: Health
Care Facilities Code, NFPA 101: Life
Safety Code and other NFPA codes,
upgrading the mechanical, electrical, plumbing, fire
protection, medical gas and technology systems will
inevitably require outages to existing systems.
Designers can learn to identify and predict system impacts and outages early during the design
phase so the conversation can occur before construction. Proper outage mitigation and planning
will save time, stress and money during construction, while minimizing concerns to patient comfort and safety.
There are no provisions in code to suspend the
requirements of an occupied facility for any duration of time. The expectation of a state licensing
authority or other authority having jurisdiction is
that the facility will meet code requirements when
occupied. While remodel or alteration projects are
expected to have impacts to the building systems,
the facility is not absolved of patient care or safety
risks during those times.
System upgrades or replacements may be due to
end-of-life replacements, AHJ enforced improvements or they can be desired by the owner after
performing the risk assessment referenced in NFPA
Figure 1: This shows an example of an operating room after equipment is added. Designers
should consider the final usage of critical care
spaces, taking into account how the room will
be used and what equipment will be added
after occupancy. Courtesy: IMEG Corp.
• Identify common system impacts to health care
occupancy patients, visitors and staff.
• Consider processes to identify system outages during
• Using NFPA 99 as a guide, understand strategies for
minimizing system outages during construction.
99 Chapter 4. The risk assessment process will also
help the team determine how to prioritize outages.
Four categories are defined as:
• Category 1: loss of life potential.
• Category 2: major injury potential.
• Category 3: disruption potential.
• Category 4: annoyance potential.
When replacing existing infrastructure, designers and owners should evaluate applicable codes
and risks associated with maintaining existing locations and configurations. In many cases, a onefor-one replacement may not be recommended
or allowed by applicable codes. Identifying these
impacts during the project budgeting stage is
important to prevent designs exceeding previously
approved budgets.
Engineers and designers can provide valuable
input during the owner’s project planning stage to
assist with determining scope and costs. When project costs do not align with project budgets, delays
can be costly and exacerbate the associated risks.
Health care projects that affect existing departments or systems can have localized or widespread
effects on a wide variety of health care departments
or systems required to provide patient care. Affected systems or departments can include:
Figure 2: This provides an example of the setup for pulling large
conductors. Projects that add breakers and cabling to existing gear
can have long outage durations due to the effort required. Courtesy:
IMEG Corp.
Figure 3: Analog
phone systems remain
in many health care
facilities and are
required to be maintained until the facility can fully upgrade
to digital systems.
Disruptions to these
systems should be
avoided. Courtesy:
IMEG Corp.
• Catherization labs.
• Critical or intensive care units.
• Dietary/kitchen coolers and equipment.
• Elevators for patient transport.
• Emergency department.
• Imaging (CT, X-ray, MRI).
• Information technology: data, phone, paging.
• Labor, delivery and recovery.
consulting-specifying engineer
June 2020
• Laboratory.
• Nurse call.
• Medical dispensing or storage.
• Morgue coolers.
• Nursery.
• Pharmacy.
• Sterile processing department.
• Surgery or procedure rooms.
• Telemetry.
Electrical systems: Chapter 6
When remodeling patient care areas, the engineer should identify if the existing electrical system is properly grounded, as referenced in Section One of the common areas of concern is the
bonding of critical branch and normal branch panelboards serving the same patient care area and the
presence of an equipment grounding conductor.
This section of code is addressing the possibility of
a difference in potential on the equipment casing or
grounding connections in the presence of a patient.
Another area of electrical concern is the segregation of essential branches for life safety, critical
and equipment branch loads. Commonly termed
“comingling,” as areas are remodeled or revised, the
Figure 4: When generators or paralleling gear are affected, system
outages may require temporary power. This image includes temporary feeders from a portable generator to facilitate switchgear revisions. Courtesy: IMEG Corp.
June 2020
engineer should identify appropriate sources for
emergency branches and notify the project team
when appropriate branches are not available.
An older facility often will have only one general emergency branch panelboard serving both
life safety loads (fire alarm, lighting, medical gas
alarms, etc.) and critical loads (patient bed receptacles, telemetry, nurse stations, etc.). NFPA 99 Sections and apply to the life safety
branch of a Type 1 and Type 2 essential electrical
system, respectively, while Section applies
to the critical branch of a Type 1 EES.
Equipment branch loads defined in Sections or should remain separate from
life safety and critical branch panels. When remodeling an existing facility, the engineer should perform a careful study of the existing panelboards and
identify when additional panels or even additional transfer switches are required to establish legal
branches for use on their project. No section of
code permits remodel projects connecting to illegitimate essential electrical system branches for cost
or convenience.
NFPA 99 references NFPA 110: Standard for
Emergency and Standby Power Systems for the
systems that supply the EES. NFPA 110 Chapter 7 includes requirement to maintain separation
between emergency power supply system equipment and normal service equipment greater than
1,000 amperes and larger than 150 volts to ground.
EPSS equipment includes transfer switches and the
distribution equipment serving the emergency side
of transfer switches.
Even though this requirement dates back to
the 1999 edition of NFPA 110, it is common for
older facilities to have both EPSS and normal service equipment in the same room. When projects
require additions or replacements of EPSS equipment, the installations should comply with current
applicable codes, which may require the creation
of a new emergency electrical room. The additional space required will need to be coordinated with
the owner early in the design phase so an appropriate cost-effective alternate location can be provided.
When electrical equipment is modified, altered
or replaced, the engineer should discuss electrical
outage impacts with the owner and affected clinical departments. Outages can occur on the normal
service equipment, emergency power supply generator sets and paralleling gear, transfer switches, distribution equipment or panelboards themselves. In
each case, a specific outage impact plan should be
discussed to determine when the work can occur
and what temporary provisions will be required to
maintain patient care.
In some instances, the design team may need
to identify alternate locations for trauma, surgery
or caesarian section procedures, which will be
required regardless of the project schedule. Furthermore, high-acuity patients in the ICU, neonatal intensive care unit, pediatric intensive care unit,
nursery or labor, delivery and recovery may require
supplemental power to remain in their respective
locations. When temporary relocation is possible,
the alternate locations will require prior approval
and planning.
Other areas affected by electrical outages include
general lighting and elevator service. Because many
health care facilities have multiple levels, temporary illumination of stairwells may be required
during associated outages. Vertical transport (elevator) outages need to be carefully evaluated so that
patients in beds are not prevented from traveling
between floors if a trauma event occurs. In these
cases, relocation of patients to the same level as surgery may be required to ensure transport ability.
Refrigeration equipment for the kitchen,
morgue, pharmacy or medicine storage are unlikely able to tolerate extended outages. Laboratory and inpatient pharmacy departments are often
required to operate continuously and any outage
will need to include provisions for alternate sources
of power and lighting. When outages impact emergency departments and trauma rooms, the health
care facility may need to go on “trauma bypass,”
meaning that other area hospitals are informed that
incoming cases will be diverted. The use of this scenario should be highly scrutinized, as it represents a
loss of revenue and high levels of coordination with
When connecting to or extending existing EPSS
equipment, outages occur even when the work is
on the de-energized emergency supply portion.
Because the standby EPS equipment can be called
upon at any time, work that requires a lock-out of
the EPS equipment puts the facility and its occupants at risk. EPS or EPSS outages require careful planning and those plans may be subject to
approval by the AHJ and or state public health
Figure 5: This illustrates an instance of coordinating fire-rated lowvoltage cabling pass-through with the cable tray. Spare capacity is
provided to minimize impacts during future remodel projects. Courtesy: IMEG Corp.
Technology systems: Chapter 7
Modern health care facilities require a constant flow of data for patient information, paging
systems, medicinal needs and patient vitals. When
projects affect the telecommunication equipment
rooms, provisions for electrical power or cooling
should be provided to prevent the loss of system
functionality during construction. NFPA 99 Sections and identify the power
requirements and environmental requirements,
respectively, for telecommunication systems spaces.
When outages to the electrical system are planned,
the design team should identify temporary or additional permanent power additions as part of the
construction documents.
Figure 6: Intercepting existing plumbing for multistory remodel projects may be required to allow for adequate ceiling heights and systems. Engineers should identify existing gravity drain piping conflicts
during design and plan for corrective action. Courtesy: IMEG Corp.
consulting-specifying engineer
June 2020
While dual power supplies with dual sources
may be currently used in the network racks, not
all systems or components will have this level of
redundancy. The current use of any uninterruptable
power supplies will need to be evaluated and coordinated with the expected outage duration.
During remodeling projects, engineers should
evaluate the existing cabling supports above accessible ceilings and plan for corrections to cable
supports for compliance with NFPA 70: National Electrical Code Article 800, which requires that
the communication cables not prevent access above
ceilings. Exhibit 800.2 illustrates communication
cables being prohibited from laying on top of suspended ceiling systems. Section 800.25 requires the
removal of abandoned cables, which may be discovered or caused by the remodel project.
The design team should review impacts
of proposed plumbing systems on adjacent
areas and discuss strategies with the owner
and clinical teams.
As projects impact existing paging systems, and
paging systems are classified as emergency communication systems, the associated equipment may
fall under the provisions of NFPA 72: National Fire
Alarm and Signaling Code Chapter 24, requiring
upgrades to both hardware and cabling. Where outages affect nurse call systems, the design team needs
to coordinate with the owner for procedures to
monitor patients and communicate patient needs,
which will determine the timing and duration of
outages or any temporary provisions.
Existing phone systems and radio systems may
be affected by electrical outages as well. While some
systems may have an UPS, the current available
runtime of the UPS will need to be evaluated and
may require supplemental power if the expected
outage is longer than the runtime of the UPS.
the maximum length of hot water system pipe and
the concerns expressed in section 2.1- for
heated potable water distribution systems.
Because the piping systems are typically hidden behind walls and above ceilings, the designers should spend time discussing the ability to
isolate piping with the facility plumbers and staff
and incorporate outage mitigation efforts into the
design. The impact of system outages due to extensions, rework or demolition will vary based on the
system and presence of isolation valves (for pressurized systems).
It is common for older buildings to lack isolation
valves by department or floor and designers should
consider adding isolation valves when outages are
scheduled to reduce future impacts during other
construction phases or other projects.
Gravity piping is a common source of conflict in
remodel projects for multilevel health care facilities
because installation requirements prohibit vertical
piping offsets that are allowable with pressurized
systems. This means that gravity piping takes precedence over other systems and may impact routing options for new systems. As a result, designers
encounter the challenge of coordinating with the
underfloor sanitary serving the floor above. The
project should identify what rework, if any, will
need to occur to existing infrastructure in order to
execute the proposed new work. Additionally, any
removal or addition of sanitary for the project will
affect the spaces below.
It may not be immediately obvious to the entire
design team that access from below may be problematic. If the project is above an ICU or a surgery
suite, the impacts are exacerbated and the level of
coordination required increases. Closing departments or relocating patients to facilitate plumbing work may be avoided by revising the project’s
floor plan — something that is easier done during
the programming or schematic design phases. The
design team should review impacts of proposed
plumbing systems on adjacent areas and discuss
strategies with the owner and clinical teams.
HVAC systems: Chapter 9
Plumbing systems: Chapter 8
NFPA 99 Section 8.3 references the Facility
Guidelines Institute for potable, nonpotable and
heating water requirements. The 2018 edition of the
FGI Guidelines documents for the design and construction of health care facilities is broken out into
three categories: hospitals, outpatient facilities and
residential health and care and support facilities.
Adoption of the FGI Guidelines varies by state,
except where required by NFPA 99. Designers will
reference the appropriate documents for their project, noting that infection control risks can exist and
the requirements of the Appendix Table A2.1-a for
June 2020
NFPA 99 Section 9.3 references ASHRAE 170:
Ventilation of Health Care Facilities. This section
also includes ventilation requirements for areas
where medical gases are stored. National energy
codes, such as International Energy Conservation
Code or the ASHRAE Standard 90.1: Energy Standard for Buildings Except Low-Rise Residential
Buildings, have an impact on how HVAC systems
are designed.
Remodeling or retrofit projects are unlikely
able to meet the new requirements using existing
equipment. Furthermore, the age and condition of
mechanical equipment may justify replacement. It is
common for designers to need more system capacity and a one-for-one replacement scheme may not
be feasible for two primary reasons. First, the physical size of new equipment may not fit in the existing
location. Second, using existing locations means long
system outages that are only tolerable if the equipment serves the construction area only.
In health care remodel, renovation or addition
projects, temporary ductwork and temporary heating, ventilation and air conditioning equipment
should be discussed and planned for during design.
Long outages to heating equipment cannot be tolerated during winter months while long outages to
cooling equipment cannot be tolerated during summer months; the severity of each is largely due to
the longitudinal location of the facility.
Because of the relationship between seasonal temperatures and HVAC equipment, projects can either
be scheduled to minimize impacts or plan for temporary equipment. Rooms storing medicines or vaccines will have strict temperature requirements and a
plan for either providing temporary conditioning or
relocating the sensitive items should be determined.
The risk assessment will identify financial impacts
and patient care impacts if medicines or vaccines are
negatively impacted due to remodel efforts.
When construction occurs in or adjacent to
existing occupied areas or where projects have
phased occupancy, the HVAC system may likely
require multiple balancing and control iterations.
Engineers should coordinate expected balancing
events with the project schedule.
The quantity and scope of system balancing
needs to be clearly identified on the construction
documents for each phase of construction. Where
supply, return or exhaust systems are impacted during construction, room pressure relationships in adjacent occupied areas can be impacted.
Section A1.2- (2) of the 2018 FGI Guidelines for hospitals addresses HVAC system outages
being discussed as part of the infection control risk
Medical gas, vacuum systems:
Chapters 5, 15
The continued operation of medical gas and
vacuum systems will vary based on the classification of system category, as defined in Chapter 4.
When outages to Category 1 systems are required,
the design team and facility need to work together to either relocate patients to unaffected areas or
develop alternate systems, such as portable gas bottles and portable vacuum equipment.
When outages to Category 2 or Category 3 systems are required, the solution may be a combination of convenient scheduling of work and
temporary systems. Alarm and warning systems
defined in NFPA 99 Section 5.1.9 should be eval-
Figure 7: Operating rooms are required to maintain positive pressure
at all times. Remodel projects affecting ductwork should take care to
not present imbalances that can affect critical care spaces. Courtesy:
IMEG Corp.
uated when projects alter or extend the existing
systems. The requirement for two or more alarm
panels includes the requirement for independent wiring to the initiating devices, as noted in
The certification requirements for medical gas
and vacuum systems extend the duration of outages that alter or modify existing infrastructure. If the
designer intends on reusing existing piping for different systems, Section apply, requiring full compliance with the provisions for the new
system. Medical gasses for oxygen, nitrogen, nitrous
oxide, carbon dioxide, instrument air, helium, waste
anesthesia gas disposal should be clearly identified,
as described in Table 5.1.11. When existing zone
valves for gas or vacuum systems are affected by
project alterations, the engineer is responsible for
determining the compliance of the existing location
and making adjustments as directed by the AHJ and
as noted in Section
Health care projects present numerous challenges to the design team and coordination with existing occupied areas is another layer of complexity.
Impacts to the existing facility are not limited to the
discussions above — they also include system routing outside the areas of construction. Identifying
outage impacts early in design can allow for design
alterations that can reduce or even prevent outages
and impacts to adjacent departments. With proper planning, the design team can reduce the occurrence of outages and thus reduce negative impacts
to patients and care providers. cse
Richard Vedvik is a senior electrical engineer and
acoustics engineer at IMEG Corp. He is a member of
the Consulting-Specifying Engineer editorial advisory board.
consulting-specifying engineer
June 2020
By Matt Short, PE, Smith Seckman Reid, Houston
How to apply
NFPA 99 in the design
of health care facilities
Examine three areas of NFPA 99 that are often discussed during
the design and construction of a health care facility
he design of a health care facility requires
engineers to “place the public welfare above all other considerations,” as
defined by the engineer’s creed. While
this is equally important in the design of
every project, health care facilities are unique in that
patients and medical staff with a wide variety of age,
health and physical ability are brought together into
a common environment.
Because occupants of hospitals are
immunocompromised or are heavily
reliant on others for care, these facilities require a focus on life safety, sys• Determine what scope is
tem reliability, infection control and
covered by NFPA 99 in hospital
many other considerations that may
not be present in other facilities.
• Highlight requirements within
There are many codes and standards
NFPA 99 that are misunderstood
engineers of health care facilities
or misapplied during design.
use to establish minimum requirements
• Discuss options engineering
for the design including NFPA 99:
teams have when encountering
Health Care Facilities Code, ASHRAE
these challenges.
170: Ventilation of Health Care Facilities and state hospital licensing regulations.
NFPA 99 “establishes criteria for levels of health
care services or systems based on risk to the patients,
staff or visitors in health care facilities to minimize the
hazards of fire, explosion and electricity.” Some of the
systems referred to within the code include electrical
power, fire alarm and both combustible and noncombustible medical gases.
Health care facilities that participate in federal
reimbursement programs are required by Centers
for Medicare & Medicaid Services to meet minimum facility condition requirements to maintain
their reimbursement status. Compliance with the
2012 edition of NFPA 99 is essential to maintaining this status.
June 2020
consulting-specifying engineer
Applying the requirements of NFPA 99 are
crucial to the health and safety of the patient as
well as the system or facility providing the care.
While the purpose of the code is clear, interpretation and application of details within the code are
often viewed differently by engineers and code
authorities. NFPA, as an organization, accounts
for this by holding a public forum on each edition release of the code to clarify some of these
Simulation centers
Health care providers are using simulation centers in their facilities to provide realistic training
to medical staff. The purpose of a simulation center depends on the service being provided. Common applications include using a simulation center
to administer hands-on training for staff on new or
changing procedures and using the space to evaluate the need for new medical equipment.
A simulation center can be used to simulate
interventional imaging procedures, surgery, labor
and delivery procedures and many other applications. The size and location of these simulation
centers varies depending on the intent of the simulation. These simulation centers may be located
in the same building or on the same floor as the
services that they are simulating, which has led to
design interpretation issues with code authorities.
The health care provider often wants to construct the simulation center as an exact replica of
the procedure it is simulating. The benefits of this
to the owner are obvious as they will be able to use
equipment, prepare procedures and have a functioning space, which allows an exact simulation
of how they will provide care to their patient in
a real-world application. Designing the simulation
Figure 1: An operating room renovation shows many elements discussed in updates to NFPA 99: Health Care Facilities Code. Courtesy:
Smith Seckman Reid Inc.
centers in this manner is costly to the owner and
has sometimes posed a conflict with adopted editions of the NFPA 99 before 2018.
NFPA 99-2012 Section Permitted
Locations for Medical Gases states that medical
gases designed to serve patient care spaces are only
permitted to be installed where the gases will be
administered “under the direction of licensed medical professionals.” There are five specific purposes
listed for the installation and use of medical gases.
The concern expressed by NFPA related to this
section of the code is that medical gases could be
serving a space that is outside the control of a medical professional that has the proper training on the
operation of these gases. NFPA intended this section of the code to ensure that these systems do not
fail or become contaminated while under the control of an untrained user. This presents a difficult
challenge for the engineer designing a simulation
center to provide an accurate simulation of these
systems in a space that is not considered acceptable
for medical gases.
A design strategy that has been used that satisfies the needs of the facility and NFPA is to simulate the medical gases being delivered to the space.
For example, in a simulation room requiring medical air, medical vacuum and oxygen, a dedicated air
compressor could be provided to deliver nonmedical compressed air to the oxygen and medical air
outlets installed within a space.
Medical vacuum systems are not usually held
to the same regulations as oxygen and medical
air systems. This is because the NFPA 99 does
Figure 2: The schematic contains a recent
design of a simulation
room, with a compressed air system
simulating medical air
and oxygen. Medical vacuum has been
served from the central system and has a
dedicated zone valve.
Courtesy: Smith Seckman Reid Inc.
not specifically mention it in its permitted locations. The description does mention all other
patient medical gases, therefore medical vacuum
can sometimes be left up to the discretion of the
code authority. Because of this, the medical vacuum required for the simulation center could be
served from the hospital’s main medical vacuum
system provided it has a dedicated zone valve to
control the simulation space or be served from a
dedicated medical vacuum pump.
It is recommended that additional signage be
provided near the medical gas outlets that indicates to the user which gases are being provided
in the simulated environment so that future renovations do not allow for the space to be used for
June 2020
patient care. The same could be said for the electrical systems and the entire simulation center itself.
This design strategy has been an acceptable
method for engineers to address the code requirement, but it does present another unique challenge
that should be paid attention to during design. It
is common for these simulation centers to have
the same medical gas outlets, booms and pedestals installed so that the end user is familiar with
the operation of this equipment. It is important for
the owner to discuss the use of simulated gases with
the manufacturer of the various medical gas outlets
to ensure the warranty on this equipment is maintained with an alternative use or gas.
It is common to have these strategy discussions
for simulation centers being designed in accordance
with NFPA 99-2012, however in NFPA 99-2018, the
design of simulation centers was addressed. NFPA
99-2018 Section includes the same verbiage as the 2012 version, however a sixth item was
added to the allowable spaces that states “simulation
centers for the education, training and assessment
of health care professionals.”
By adding simulation centers as a permitted
location for medical gases, NFPA recognizes that a
true simulation of these systems is essential to the
training of medical staff. It is important for design
teams to understand which version of the NFPA
99 has been adopted so that proper application for
these simulation centers can be applied.
Wet procedure locations
What constitutes a “wet procedure,” and where
these occur in a health care facility has long been a
discussion among design teams. The term “wet procedure location” is referenced seven times in NFPA
99, with cross references to NFPA 70: National
Electrical Code. The premise behind this term is to
reduce the risk of electrical shock to a patient in a
treatment area that is a wet environment. With such
an important safety measure to consider and with
such a broad scope, it is apparent why this code language is so heavily discussed.
Who defines where a wet procedure is performed and who is responsible for maintaining
design consistency in a wide variety of services,
providers, etc.? NFPA 99-2012 Section states
that it is the “responsibility of the governing body of
the health care organization to designate wet procedure locations.” This implies that officials within the
health care organization have authority to define a
wet procedure and where those procedures occur.
These officials could be the risk management, the
chief nursing officer, etc. The 2018 edition of NFPA
99 has revised the term “governing body” to “health
care facility governing body” to provide clarity on
these responsibilities.
The owner of the facility should provide input
to aid the design team in determining what spaces
should be should be designed with additional protection based on the specific procedures that will
be performed. Further clarification is provided in
NFPA 99-2012 Section 3.3.184 where it is stated
that a wet procedure location is “where a procedure
is performed that is normally subject to wet conditions while a patient is present.” Per NFPA, this
does not include routine housekeeping procedures
where a wet environment might be present in the
absence of a patient.
Some health care spaces such as patient beds
and operating rooms are specifically referenced
in the code. NFPA 99-2012 Section
states that “patient beds, toilets and wash basins
shall not be considered a wet procedure location,”
while states that “operating rooms shall
be considered a wet procedure location.” NFPA
Figure 3: An isolation panel is installed in a
hospital operating room. Courtesy: Smith
Seckman Reid Inc.
June 2020
99-2012 Section goes on to allow the
health care organization the option to perform a
risk assessment of the operating room to potentially define the space otherwise. NFPA 99 Annex A,
A., specifies that, “In conducting a risk
assessment, the health care governing body should
consult with all relevant parties, including, but not
limited to, clinicians, biomedical engineering staff
and facility safety engineering staff. This is important to consider for any facility considering this
atypical approach.”
With the safety of the patient being the goal of
these code requirements, it is fair to question why
an argument even exists over which space is a wet
procedure location.
Understanding the design and maintenance
requirements of a wet procedure location is an
important element in the debate. NFPA 99-2012
Section states that “wet procedure locations shall be provided with special protection
against electrical shock,” and defines
that protection as a “power distribution system that
inherently limits the possible ground fault current
due to a first fault to a low-value, without interrupting the power supply.”
With further clarification provided in the
National Electric Code, engineers address this
requirement by installing an electrical isolation
panel within the space. These panels are provided
with line isolation monitors, isolation transformers
and are fed from a transfer switch, which is often
dedicated to the panel. It is the line isolation transformer in these panels that is used to isolate what
would have been the neutral from the ground.
Advances in technology and a significant increase
in the amount of electrically operated medical equipment within operating rooms and major procedure rooms increases the number of branch circuits
required. This may increase number or capacity of
isolation panels that are required to support a space.
Recognizing that isolated power adds to the construction and maintenance cost, it is important to
understand which spaces will in fact be used for wet
procedures. With a detailed review of each project’s
needs and intentionally defining these wet procedure locations early in the design process, the engineer and owner can plan for an appropriate design.
Intervening walls
Medical gases used in patient care areas are
required to have zone valves to control the flow of
these gases to certain zones or areas within a facility. The intent of the zone valves are to shut off the
flow of gas to a fire site (hazardous area) without
staff being directly exposed to the fire or any product of combustion created in the space and allow
staff to safely evacuate patients to another area of
the building.
Figure 4: A medical gas zone valve
and alarm panel are
installed in an emergency department.
Courtesy: Smith
Seckman Reid Inc.
Medical staff in health care facilities are properly trained on how to operate these valves during
an emergency event. While the purpose of these
zone valves is generally understood, locating them
to meet code requirements can often be in conflict with the architectural design of a space. This is
most commonly an issue in large, open spaces such
as recovery or open-bay care units where there is
limited wall space.
NFPA 99-2012 Section states that “all
station outlets/inlets shall be supplied through a
zone valve, which shall be placed as follows: 1. The
zone valve shall be placed such that a wall intervenes between the valve and outlets that it controls.
2. The zone valve shall serve only outlets located on
that same story. 3. The zone valve shall not be located in a room with station outlets that it controls.”
All three requirements of the zone valve location mentioned above are for the safety of the individual who would be controlling the valves. If an
intervening wall is used, it may be either opaque
or not, however it must be constructed with a onehour fire rating.
consulting-specifying engineer
June 2020
The challenge that engineers often face in a
largely open patient care area is that there are few
walls that will accommodate the zone valves. Adjacent spaces outside these patient care areas may not
be suitable for the installation of a zone valve. An
example of this would be a patient waiting area.
In this situation, an intervening wall in the patient
area would be required.
A common strategy used by designers to design
the required intervening walls while still maintaining the functional layout of a larger space is to
construct a partial wall or “wing wall.” These wing
walls can be constructed with glass that allows
the line-of-sight to be maintained across a large
space. This seems like an effective solution, however there are a few items to consider when using
this design.
First, it is important to consider how the medical gas piping can be installed with the window and
the height of the zone valve must also be properly coordinated. The height of the valves is dictated by NFPA 99 where it is mentioned that the zone
valves “Must be readily operable from a standing
position.” This creates a challenge during construction to properly install the medical gas piping while
maintaining the height of the zone valves and a
glass opening in the wall.
Second, when locating these zone valves, the
intervening wall must be fire rated to protect the
operator of the valves. In a wing wall with a glass
element, the glass must be fire rated and installed
with a UL listed installation. This can be much
more costly to the owner of the facility and there
are limited products available when compared to a
nonfire rated material.
Ultimately, the installation of zone valves in an
intervening wall is crucial for the protection of the
patient and medical staff. Although it can be challenging, when carefully planned by the design team
and owner, a space can function properly and meet
the intent of the code.
The design of health care facilities offers many
challenges for the design team and owner of the
facility. Adherence to codes and standards such
as NFPA 99 will help to ensure the design is safe
for all occupants. Some code requirements may be
difficult to apply, but with a proper understanding and heightened communication between the
design team and owner, Successful design can be
achieved. cse
Matt Short is a project manager/mechanical engineer
at Smith Seckman Reid. He is a member of the Consulting-Specifying Engineer editorial advisory board.
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By Sal Bonetto, RCDD, CDT, CannonDesign, Buffalo, N.Y. and Donald Rosen, CPD, CannonDesign, Boston
How to apply
NFPA 99 to medical gas,
telecommunication systems
Engineers should understand NFPA 99 — along with other guidelines
and codes — when designing health care facilities
FPA 99: Health Care Facilities Code
covers various systems relative to
health care facility design. NFPA 99
applies to all health care facilities
other than home care or veterinary
care. Requirements are applicable to new construction and equipment.
Existing building system upgrades are needed
only if new construction negatively impacts the
systems’ overall performance or if the existing systems — particularly source equipment — do not
meet the current NFPA 99 guidelines to support
and meet the requirements to support the new use
or program. Any design criteria implemented in a
Figure 1: This is an example of a typical zone valve box without an
area alarm, for general care use. The use of an alarm should be evaluated by hospital administrators. Courtesy: CannonDesign
June 2020
consulting-specifying engineer
facility must ultimately meet the approval of the
authority having jurisdiction.
The documents included in NFPA’s codes,
guidelines and standards are intended to work
together as a total package. The acceptance of specific NFPA guidelines by the particular AHJ and
as required by the Facility Guidelines Institute and
local building codes, form the basic design criteria
for the engineered hospital systems and their use.
Clients may choose to provide systems or criteria that are above and beyond these basic requirements for their specific facility or campus. It is
also important to note that NFPA may update or
supersede certain items by issuing tentative interim
amendments or errata at any time. These modifications and information are evaluated as they apply
to the client’s needs and requirements.
Design engineers and architects involved in
health care engineering design are constantly referring to these guidelines as they prepare
their designs and documentation. In addition
to these guidelines, the design is often impacted by the acceptance from the local department
of health, Health and Human Services, the Centers for Medicare & Medicaid Services, the Food
& Drug Administration and the National Institutes
of Health. Additional agencies that will have input
into certain aspects of the requirements could
include the Centers for Disease Control and Prevention, Occupational Safety and Health Administration, ASHRAE and American Society for Health
Care Engineering.
The use of the included terms, acronyms and
common phrases that appear in the NFPA guidelines should be integral to the designer’s vocabulary
and represented in the documentation. Providing
uniformity between these references and the design
documentation is extremely important to ensure
proper understanding of the design intent.
The risk categories identified and described in
NFPA 99 Chapter 4: Fundamentals relate to the
classification of areas and related systems for the
application of specific guidelines. There are four
categories of risk defined. Generally, the categories
are established based on the risk of life, with Category 1 being the most stringent where failure of
systems is likely to cause major injury or death to
patients, staff or visitors. The other end of the spectrum, at Category 4, the failure of equipment and
systems would not cause any impact to patient care.
General considerations
The requirements and standards identified in
the NFPA 99 and the FGI guidelines provide the
minimal requirements for any health care facility design and construction. Based on the adoption of these standards and the understanding of
the systems to be installed and the required basis
of design, it is with this understanding that we use
Chapters 4 through 11 of NFPA 99.
With the input of the client, the risk category
can be established. Specific design criteria can be
verified and then reinforced or form the basis with
various users of the facilities, which may have additional requirements that will need to be integrated
into the overall building systems that will ultimately
create the basis of design for the facility.
Medical gas systems
The design and installation of medical gas and
medical vacuum systems relate directly to the client’s determination of compliance with regulatory
authorities and the category of use. The determination of these categories relative to the area requirements for anesthetizing, critical care and general
care systems or ambulatory services are based on
the user’s needs, program and the requirements of
the specific layout.
All medical gas systems are required to be constructed of piping that is a minimum of type L copper tubing, washed and capped for oxygen use, with
brazed joints. During the brazing process, the piping is continuously being purged with hospitalgrade nitrogen. The use of three-piece valves is
required so that the valves are not damaged while
brazing at a temperature of approximately 1,000°F.
When evaluating the source equipment requirements, the preferred type and sizing of source
equipment, there are many criteria to consider. At
this time, there are very few applications for watersealed pumps. Water-sealed pumps could still be
considered for a “dedicated” waste anesthesia gas
disposal system if the need arises.
There are some areas of the country and there
are some clients who prefer water-sealed pumps,
based on the related water use and cost. There are
many other “dry” types or oil-sealed equipment.
From many years of using various systems, the dry
Figure 2: This is an example of a typical zone valve box for critical
care use. Alarm sensors are between the zone valve box and the
patient. Courtesy: CannonDesign
vacuum, oil-less rotary vane, claw and
rotary screw and oil-less reciprocating or
scroll compressors are the most common
selection for health care applications for • Understand how NFPA 99 works
with other codes, standards and
pump operation.
guidelines in hospitals.
The additional piped nonflammable,
medical gases such as oxygen and other • Provide an understanding of
guidelines for medical gas
required gases including nitrous oxide,
carbon dioxide or high-pressure nitrogen
are commonly stored as high-pressure in • Review telecommunication and
information technology codes in
manifolded cylinders or cryogenic, lowhealth care facilities.
temperature liquid bulk or mini-bulk
systems. These systems include either
cryogenic backup or gaseous backup, but all the
medical gas systems require redundancy.
The need for redundancy of systems is identified in NFPA 99. Redundancy can take the form of
multiple pumps, secondary gas system with automatic switchover or multiple skids of equipment at
various locations throughout a facility. This equipment arrangement can take various forms, with
the requirement that the system can support the
required flow at the required pressure or level of
vacuum if one portion of the system fails to operate properly. The manifolded gas systems would
require a duplicate second bank of cylinders with
automatic switchover. All systems shall be connected to a form of emergency power.
Some items to consider when looking at the
placement and sizing of the required equipment:
• In addition to validating the engineers sizing of source equipment with the supplying
vendor, the calculated line size that serves the
facility should be approximately the same size
as the source outlet piping serving that portion of the facility.
consulting-specifying engineer
June 2020
Figure 3: Hospital rooms require many different systems, including
medical gas and medical air systems. This intensive care unit room
included several hook-ups for electrical, gas and other equipment.
Courtesy: CFE Media
• The use of skid-mounted, multiple, smaller capacity pumps and compressors allow
for redundancy by supplying an additional
smaller unit. This concept allows for varied
flow, with the units coming online as they are
required by the usage, but with the redundant
unit always at rest.
• The installation of vacuum exhaust and medical air intake piping will need to be sized in
accordance with the vacuum pump or medical air compressor suppling manufacturer recommendations. Normally, based on required
length, offsets need to occur and a need to
have very little dynamic friction loss; the line
can become very large very quickly. The piping, unless approved to be of a different material, should be the same piping system types as
the distribution to the health care facility.
The piped medical gases, other than medical air,
are commonly provided through source storage of
gas or liquid that is vaporized through changes in
June 2020
consulting-specifying engineer
The most common system to be stored as a
liquid is oxygen. Gaseous oxygen is a commonly used medical gas in a health care facility. The
bulk oxygen source equipment normally includes
cryogenic backup storage, vaporizers, ambient
temperature heat exchangers, pressure-regulating
valve, isolation valve and the appropriate source
system alarm points.
Another aspect of oxygen supply to a health care
facility could include the delivery of a separate oxygen line at an elevated pressure to supply the health
care facilities requirements for an oxygen enriched
environment within a hyperbaric chamber.
In addition, because if the nature of the bulk
storage system being a certain exterior location subject to harm or possible interruption, the oxygen
system must include a remotely located, emergency
oxygen connection. This is to provide an auxiliary
connection point accommodating a delivery tank
truck, to ensure continued delivery of 55 pounds
per square inch gauge oxygen to the patients requiring oxygen for respiration and inhalation.
The remaining common medical gases consumed through patients use in various processes are
nitrous oxide and carbon dioxide. Nitrous oxide as
an anesthetizing agent and carbon dioxide as a suitable gas for the expansion of a patient’s abdomen.
Based the quantity of use for these gases, the source
system is normally gas storage cylinders at a storage
pressure of approximately 2,000 psig. The gases are
released and reduced to a pressure of approximately
55 psig for delivery to the facility. The redundancy
of these systems is a double-loaded manifold with
the same quantity of primary and secondary cylinders and automatic switchover manifold.
Care should be taken to work with the independent medical gas certifier to ensure that the work
agrees with the interpretation of the inspector, or if
the inspector has not interpreted the system properly. The misunderstanding or unclear documentation
can lead to confusion and additional time and costs
to the owner. To avoid this, a clear presentation shall
be made to the owner in the presence of the independent testing agency before installation of the systems.
Medical air systems
The oil-less medical air compressor systems,
as specified and applied, should be provided as
a complete skid system with “makeup” to a storage receiver, allowing for cycling of the compressors. Depending on the supplier and the capacity
required for the system, the dryers and or final
treatment could be located on separate skids and
require induvial electric connections.
The sequence is normally set up as primary and
secondary and the multiple units operate as is a leadlag system with alternating lead compressors to allow
for even usage across all of the compressor units. The
other components of the systems include intake filtration, dryers (refrigerated or desiccant), filters,
carbon monoxide monitor, dewpoint monitor and
regulators. All components shall be duplexed and
valved with a bypass for maintenance and isolation.
The medical air usage requirements, both pressure and flow, require that there is a sufficient volume of compressed air for the worst-case situations.
The source equipment is selected with a limited
amount of diversity as established standards. The
delivery pressure to the building is normally in the
range of 55 psig. The pressure generated at the compressors must account for loss occurring at the dryers and filters up to the main pressure regulators,
in addition to the dynamic loss through the piping
system out to the point of use. In the case of supplying medical compressed air to ventilators, normally
mixed with oxygen, it usually is an instantaneous
loading that can be accomplished through proper
pipe sizing and accommodations within the source
system, once the quantity of units and the “inflating” volume of the specific ventilators are known.
The “source” pressure regulating station would
be the last component of the equipment, upstream
of the monitoring and alarm functions. The compressed air generated up to the regulators can be as
high as 100 psig. The piping pressure loss can be
selected by the designer, based on the requirements
of line pressure, capabilities of the compressors
and the required point of use pressure and volume
requirement. There are many things to be consid-
Figure 4: This is an example of a typical zone valve box for anesthetizing location use. Alarm sensors are upstream of the zone valve
box, based on the anesthesia equipment in the operating room.
Courtesy: CannonDesign
ered with respect to supplying compressed air to a
building occupant.
Common piping dynamic losses through the
piped distribution can be designed for 4 to 5 psi for
55 psi systems. The process is to estimate the total
developed length from the regulator to point of use
farthest away with the required residual pressure
at the required flow.
Figure 6: This is an example of a master medical gas alarm panel and system required for all medical gas and vacuum
equipment. Courtesy: CannonDesign
consulting-specifying engineer
June 2020
All medical air systems, piping, valves and
components must be in accordance with the
most recent edition of NFPA 99. There are different levels of medical air piping systems that
apply to specific facilities, such as general hospitals, ambulatory facilities, dental, etc. For our
designs, the ambulatory facility will be addressed
as a hospital condition unless directed otherwise
by the owner.
Various users will require multiple pump
arrangements and multiple separators to
allow for periodic shutdown and required
Medical vacuum systems
Medical vacuum is normally considered a “dry”
system and the system includes a “trap” or bottle at
the point of use, using the adjacent “slide” to hold
the trap bottle.
The delivery is 11 to 15 inches mercury for
patient rooms and general use, at times it is
required to have an elevated vacuum level at surgery areas that elevated vacuum could be in the
vicinity of 15 inches mercury. If the user has a
need for a “higher” level of vacuum, this would
necessitate the installation of a dedicated pump
system and piped system. The flow at the inlet is
based on the use, normally it varies from 1.0 standard cubic feet per minute based on the system
conditions in a patient room and a value to 3½ to
4.0 SCFM per outlet for operating rooms or special procedures. No diversity should be applied to
the surgery areas or similar predetermined areas.
Other vacuum systems such as waste anesthetizing gas disposal through a dedicated medical
vacuum system or connected into the hospital’s
medical vacuum, a distance of 5 feet from the
room inlet fitting or, more appropriately, at a location immediately downstream of the zone valve
box serves the anesthetizing area.
All source equipment systems shall have multiple pumps. All system components, alarms and
monitoring shall be in accordance with the latest
adopted NFPA guidelines. The system component
and pump sizing need to be in accordance with the
manufacturer’s recommendations. Once the engineer has established the intended capacity and sizing, it shall be reviewed to validate the sizing and
ensuring the manufacturer’s warranty.
June 2020
The system can be either a rotary vane, claw or a
liquid ring system. If the system is intended to handle WAGD, do not use a rotary vane system; the
function of the rotary vanes is not compatible. Any
use of water seal shall be reviewed to include water
reclaim or recirculation to limit the disposal of once
through seal water. A customary approach is to provide a dry rotary vane pump set and galvanized
tank/receiver, when WAGD is not being introduced
to the piping system. System pressure drop across
the piping network shall be a maximum of 5 inches
mercury at the calculated demand flow.
To use various measurements of air and the
conversion at levels of vacuum, specifically actual
cubic feet per minute minus SCFM.
Waste anesthesia gas disposal
The installation of the waste anesthesia gas
disposal system is required to “collect” the waste
anesthesia from the locations using anesthesia gas
through the anesthesia machine. The release of the
waste anesthesia gases to the room can cause harm
inadvertently to the patient and the attending surgeons, nurses and staff within the room.
The collection of WAGD can occur either by a
dedicated system or as a connection into the medical vacuum system. The piping connection to the
medical vacuum system is allowed a distance of 5
feet from the room inlet fitting or more appropriately at a location immediately downstream of the
zone valve box serving the anesthetizing area.
Dental vacuum system
The dental vacuum system is a low vacuum level system, more similar to a fan-type unit,
developing vacuum levels of only approximately
6 inches mercury. The minimum system demand,
unless noted by the user, is based on approximately 198 liters per minute (7 SCFM) per dental chair and at an operating pressure of 21 to 27
kilopascals (6 to 8 inches mercury). A minimum
of vacuum of 21 kPa (6 inches mercury) shall be
maintained at the most distant outlet. The dental vacuum system is a partially wet system that
will carry some particles through the system. The
piping system shall include an amalgam separator on the piping system before the vacuum source
blower(s) system to keep the debris from entering
the vacuum source equipment. The separator must
include a sight glass and level alarm, for visual
observations of liquid and material.
Various users will require multiple pump
arrangements and multiple separators to allow
for periodic shutdown and required maintenance.
The common piping system is polyvinyl chloride
or other plastic piping system. Be aware not to run
this system through a plenum without proper precautions and fire rated applications.
Alarm systems
Medical master and area gas and vacuum alarm
systems are required in accordance with NFPA 99,
all systems are required to be alarmed and certified
by an independent inspector, normally hired by the
hospital or facility.
Information technology,
communication systems
The infrastructure design is heavily impacted
by the requirements in NFPA 99, FGI and other
governing codes and has increased the necessity
for design engineers focused on structured cabling
and low-voltage communication systems to
become involved in hospital design at the onset of
a project to ensure proper space planning for telecommunications services and equipment. When
reviewing the requirements of FGI and NFPA 99,
there are discrepancies that lead to some extensive
requirements. It is important to understand the
challenges and inform the AHJ of any items that
increase space requirements without necessity to
reduce overall costs.
NFPA 99Chapter 7 applies to all new health
care facilities and new construction. Existing
systems that have portions renovated, shall be
upgraded to meet any updated code. If upgrades
to the system negatively impact the overall system,
it should be upgraded to eliminate that impact. An
existing system that does not comply may contin-
ue to remain in use if the AHJ determines it is not
a distinct hazard to life.
There are three main subject areas compiled
within Chapter 7 that are descriptive and several more that are reserved for future development. The “premises distribution system” section
includes fiber/copper cabling systems and telecommunications space and pathways. It provides
references to Telecommunications Industry Association 568-B: Commercial Building Telecommunications Cabling Standard and TIA 606-B:
Administration Standard for Telecommunications
Infrastructure, which are industry standards for
commercial building telecommunications cabling
and administration of cabling infrastructure. It
also partitions each section by category to ensure
that each of the systems of NFPA 99 Chapter 7
meet the mandated risk assessment.
Category 1 systems require two physically separated service entrance pathways into a facility.
This requirement increases the reliability of the
service into the building. Furthermore, the term
physically separated is defined as 20 feet between
entrances, which reduces the risk of an outage by
any service/maintenance on the grounds being
disrupted by any below-grade level construction.
If the facility being designed has a remotely located primary data center, two dedicated
entrance facilities are mandated again requiring
two service entrance pathways. It is common
Figure 7: Packaged medical air source equipment provides oil-less medical compressed air for patient use. Note that the
intake must be away from exhaust vent terminals and similar potential sources of contamination. Courtesy: CannonDesign
consulting-specifying engineer
June 2020
for hospitals to use cloud computing and have
resources located remote to the building. Service entrance redundancy is paramount in hospital design and should be considered for the entire
designed route as well as using multiple service
providers to ensure uptime. With many health care
systems obtaining remote facilities or facilities trying to centralize data infrastructure, routing diversity is a positive redundant design approach.
The entrance facilities shall be located as close as
practical to the building entrance point and not be
subject to flooding. The entrance facilities shall be
dedicated to low-voltage communications systems
and not contain any mechanical or electrical equipment or fixtures not directly related to the operation
of the entrance facilities. This requirement includes
sprinkler piping that does not branch off and create
an endpoint in the telecommunication space.
Each health care facility is required to have a
telecommunications equipment room to house
application servers, network equipment and storage devices. Based on size and location, it can be
collocated with an entrance facility. However, it
must be located away from exterior curtain walls
in some geographic areas which may be prone to
hurricanes or tornadoes. Facilities using a remote
data center or cloud solutions tend to have nominal servers on-site with the exception building
automation system or security solution servers.
Telecommunications rooms are also required to
support communications services throughout the
building. A minimum of one TR is required per
floor and shall serve a maximum of 20,000 square
feet of usable space on a single floor. In addition,
communications cabling must not exceed 295 feet
in pathway length. These items will allow Ethernet cabling installations and the functionality of
power over Ethernet services to support low-voltage systems within a hospital.
There is a push for gigabit passive optical network installations in health care facilities, which do
not have the length limitations of Ethernet cabling.
Using these networks does not eliminate the need
for telecommunication spaces which also provide
power via the Ethernet cabling system for many
systems. PoE solutions are a great way of providing
uninterruptible power to “internet of things” devices without additional coordination of uninterruptible power supply or emergency power outlets.
Like the telecommunications equipment room
and entrance facilities, telecommunications rooms
have environmental and security requirements.
These spaces shall have a positive pressure differential, controlled temperature and humidity to
meet the installed equipment specifications. These
spaces shall have restricted and controlled access
and not be located in a sterile area. The spaces
shall also be designed to avoid vibration and damage from water. Stacking telecommunication spaces in a building is highly recommended to simplify
riser installation, but not required.
NFPA 99 does not provide or recommend
sizes for telecommunications spaces. Telecommunications equipment rooms, entrance facilities and telecommunications room spaces are
only required to provide working clearances about
racks and cabinets to meet NFPA 70: National
Electrical Code Chapter 110.26 (A). This requirement calls for 3 feet of clearance in front of 120volt equipment for maintenance.
Figure 8: Packaged
medical vacuum
source equipment
provides oil-less
vacuum for patient
use. Note that the
exhaust terminal
point must be away
from intakes, windows and pedestrians. Courtesy: CannonDesign
June 2020
consulting-specifying engineer
Although FGI requires more space and more
confusion, the NFPA 72 reference is a much
more accurate way of depicting the actual working space requirements in a telecommunications
room because working space is only required at
the front and rear of racks/cabinets or in front of
panels. This allows engineers to design and layout
the room as it is intended.
Connectivity of services is also called out in
this section. Redundant pathways are required
between the entrance facilities and telecommunications rooms for Category 1 systems. This
requirement is eliminated in Category 2 systems,
which have a lower risk assessment. Category 3
systems additionally eliminate the dual service
entrances for the building.
Nurse call stations
NFPA 99 addresses nurse call within other communications systems. The nurse call system provides vital communications between patients and
caregivers and between caregivers in a health care
facility. All nurse call systems shall be UL 1069:
Standard for Hospital Signaling and Nurse Call
Equipment listed and consist of an audiovisual type
(two-way voice communications) system or tonevisual type system listed for the purpose.
NFPA 99 refers to FGI for the placement of
nurse call devices throughout the health care space
and supplements that information with some listed requirements. For patient area call stations, each
patient bed location shall have a call station and that
call station can serve up to two patient beds if it is an
audiovisual system. Bath stations are required at an
inpatient toilet, bath, shower and shall be accessible
to a patient lying on the floor by use of a pull cord.
Staff emergency call and code call stations are
permitted in areas that do not require two-way
voice communications because the patient is under
constant visual surveillance in such areas as preoperative and recovery. Dementia units have special requirements such as tamper-resistant features,
removal or covering of devices and limited cord
lengths of 6 inches.
Nurse call systems are not required in psychiatric units, except for seclusion/ante spaces where a
staff emergency station is required.
Finally, the resultant activation of a nurse call
device is listed in notifications signals. Staff emergency calls and code calls shall be visibly and
audibly identifiable from other nurse call signals increasing the recognition of the calls. These
parameters require initiation of the associated dome
light in the corridor, zone dome light at intersections leading to the dome light when not visible
from the nurses’ station, nurse master station originating station and each audio calling station indicating voice circuit operation.
The single differentiator for Category 2 or
higher systems is that code calls and medical
device alarms are not required for annunciation in
these facilities.
Clinical information systems are a new addition to NFPA 99-2018. It identifies the clinical
network requirements for a dedicated network
infrastructure for use by clinicians and patients
and all manufacturer’s equipment that is connected to the network. It provides for a network
NFPA 99 refers to FGI for the placement
of nurse call devices throughout the health
care space and supplements that information with some listed requirements.
that is now allowed to transport medical systems
information on an owner-provided infrastructure
resolving the solution of alarms on nurse call systems that are UL 1069 listed to operate using an
Ethernet network. In previous editions, the nurse
call system required a fixed, proprietary connection to route emergency notifications to areas
between telecommunication rooms that were connected by backbone fiber cabling. That is no longer required.
The clinical IT network shall have redundant, operable supervised segments for the backbone and they shall not share traffic. Individual
addressable devices shall be allowed to be connected as a single endpoint. If multiple devices
are connected on the same segment, a supervisory loop shall be incorporated. Each of these items
improves the reliability of the system and increases
patient safety.
Wireless phone and paging integration are also
new to the 2018 edition. It identifies the use of
communications handsets (wireless phones) for
clinical operations such that alarms and alerts
are managed similarly to the other clinical IT
It is the health care facility’s responsibility to
maintain and be accountable for the clinical IT
network and all of its components. All information and systems shall be documented and events
shall be evaluated, with risks reassessed to verify all processes to ensure corrective precautions
are taking place. The health care facility clinical
IT risk manager shall be appointed to verify this
work. cse
Sal Bonetto is a vice president at CannonDesign.
Donald Rosen is a vice president at CannonDesign.
consulting-specifying engineer
June 2020
By Scott Battles, SmithGroup, Boston; Jonathan Hulke, PE, CEM, WELL AP, LEED AP BD+C, SmithGroup, Boston; and
Stet Sanborn, AIA, NCARB, CPHC, LEED AP, SmithGroup, San Francisco
Strategies to improve
chiller plant performance,
Learn how to design chilled water systems that meet the thermal
comfort demands and achieve operational and energy efficiencies
or many buildings, the chilled water
system provides tremendous potential for creating energy savings. However, because of the role the chilled water
system plays in thermal comfort of the
building occupants, those potential energy savings strategies are not always pursued in favor
of traditional approaches. It is possible to design
chilled water systems that meet the thermal comfort demands of the building and achieve operational and energy efficiencies that can significantly
decrease ongoing operational costs.
Chilled water distribution
The chilled water distribution system must be
evaluated before a new chiller plant design or existing chiller plant upgrade can be finalized. There are
several factors to consider including:
• Existing or proposed design delta T, or lower
water return temperatures.
• Maximum and minimum chilled water
supply temperatures.
• Type of chilled water system control valves,
installed or proposed (three-way or two-way
• Significant pressure drop differences in the
chilled water piping distribution loops.
• Terminal equipment, proposed or installed.
The impact of these criteria will guide the
chilled water plant production decisions and the
most efficient pumping arrangement.
June 2020
consulting-specifying engineer
The most common types of chiller plant pumping arrangements are constant flow, primary-secondary variable flow and variable primary flow
systems. For the vast majority of chilled water
plants, the energy efficiency of the plant can be
maximized by varying the pumping capacity to
match the required thermal load. When the pumping capacity matches the thermal load, it increases the temperature difference between the chilled
water supply temperature and chilled water return
This is known as the chilled water system delta
T, and the higher the delta T, the lower the pumping energy required for the system. Increasing the
temperature difference between the chilled water
supply and return takes full advantage of the total
capacity of the chillers; variable primary flow systems typically have a lower first cost than primarysecondary variable flow systems.
Upgrading an existing constant flow or primarysecondary flow chilled water plant to a variable primary flow chilled water plant that is connected to
a distribution system with three-way valves would
result in a constant flow system with a low delta T,
for a large range of the chilled water plant’s operation. Providing a variable flow chilled water plant
that is connected to a chilled water distribution piping network with two or more substantially different pressure drops could result in significantly less
pump energy savings and the potential for the existing control valves leaking by in the lower pressure
drop chilled water loop.
Alterations in the existing distribution system are required in many chiller plant upgrades
and they should not be overlooked in the proper
design of an upgraded plant. Changing the threeway control valves to two-way control valves and
evaluating the use of two-way pressure independent control valves will solve many of these distribution issues. The existing chilled water coils were
likely not selected to perform with the 2019 edition of ASHRAE Standard 90.1: Energy Standard
for Buildings Except Low-Rise Residential Buildings required 15°F temperature difference between
entering and leaving water temperature.
Evaluating the existing chilled water coils
at varying chilled water supply temperatures is
required to determine if the coils must be replaced
or what temperature differences can be achieved
with the existing coils (see Figure 1).
Pumping arrangements
Once the chilled water distribution parameters are understood, the chilled water pumping
arrangement can be designed. A variable primary
flow pumping system is typically the most energyefficient system and provides the benefit of fewer
pumps in the system. Operating the variable primary pumps in parallel to match the optimum
efficiency point on the chilled water distribution
system curve is an effective way to minimize the
system pumping energy.
Several pump manufacturers offer sensorless pumps with integral variable frequency drives
that have the pump curves implanted in the pump
VFD, and can operate single or multiple pumps at
the most efficient point on the system curve. These
Figure 1: At the Ford Field chiller plant in Detroit, evaluating the
existing chilled water coils at varying chilled water supply temperatures is required. Courtesy: SmithGroup
pumps are a very cost-effective way to
limit the number of field mounted sensors and controls while minimizing pump
• Learn about the impact of
energy usage.
pumping schemes and plant
Variable flow condenser water systems
optimization of chilled water
are also a way to reduce the total pump
energy used in the chilled water plant.
• Understand how and when
Care must be taken when reducing the
to consider a waterside
flow in a condenser water system to avoid
suspended solids from settling out in the • Review how and when to deploy
system. Minimum flow rates are impora heat recovery chiller.
tant to maintain in the cooling towers to
ensure that the cooling tower fill remains fully wetted. Minimum flow rates must also be maintained
within the condenser section of the chiller. Even
with the potential concerns, variable flow in the
condenser water system is still a viable option and
can further reduce the overall kilowatt per ton of
chiller water produced throughout the entire range
of plant operation.
Chiller plant optimization
Optimization is the action of making the best or
most effective use of a situation or resource. What
this means for a chilled water plant, as dictated by
consulting-specifying engineer
June 2020
Integrated waterside economizer
Figure 2: In this
waterside economizer
system diagram, when
the economizers are
optimized alongside
each of these influencing
systems, then the potential benefits of waterside
economizing increase. Courtesy: SmithGroup
ASHRAE Standard 90.1 and the International Energy Conservation Code, is controlling the associated
equipment, whether new or existing, to operate as
efficiently as possible and ultimately consume the
least amount of energy, while meeting the building needs. There are different levels of optimization currently being applied in the industry ranging
from simple sequencing of the equipment to the
installation of electrical usage metering to enable
system adjustments in real time through software.
Currently, some controls manufacturers integrate plant optimization into their standard control
package. This is typically limited to inputting project
specific equipment performance data into the control software, which will, in turn, sequence a specified number of chillers, cooling towers and pumps
based on operational “sweet spots” to meet building
load. This could also include using control sequences such as pump differential pressure reset and optimum start controls for systems using setback control.
The next level of optimization is through standalone software packages, which operate in the background using proprietary algorithms and work in
conjunction with the building management system.
This typically involves the installation of electrical
energy usage meters for real time data collection
in determining equipment sequencing as well as
implementing predictive actions based on the software algorithms.
Equipment manufacturers are also starting to
include aspects of optimization into their onboard
controls as well. For example, a centrifugal chiller with multiple compressors having the ability to
June 2020
stage them on and off based on operating at the
lowest kilowatts per ton possible.
From an owner’s perspective, implementing
some form of chilled water plant optimization can
be appealing for a couple different reasons. For
example, referencing strategies in ASHRAE 90.1,
this could mean using pumps with integral VFDs
for a variable flow system or using chilled water
reset in a system with integrated waterside economizer as described in the section below. There is the
obvious reduction in energy usage, which directly
translates to dollars saved with the utility company.
Optimization is also appealing because it tends
to prolong the life of the installed equipment.
To truly understand the benefits of chiller plant
optimization, it is recommended to complete a
baseline analysis of the existing system or new
installation to help validate the benefits to system
performance. Establishing a baseline is an important aspect of this process especially as it relates to
return on investment as there is a premium associated with chilled water plant optimization.
An important aspect to note is owner and
plant operator buy-in to the software to allow it
to operate as intended. For example, in a scenario
where two chillers are operating, the software may
sequence three chilled water pumps online where
traditionally there may only be two. This would
happen because three pumps operating at a lower
frequency may use less energy that two pumps
operating at 60 hertz. Scenarios like this can be
difficult for operators to accept after operating in
a more traditional way for many years.
The best results from optimization are achieved
when all of the system equipment is sized appropriately to meet the actual chilled water demand
and not over or undersized. It is common that
equipment in older chilled water plants were
selected based on the peak load and not the total
operating range of the plant. Those plants were
often designed as constant volume systems, so a
load study that considers the actual program of
the building is recommended before sizing a plant
upgrade and/or replacement.
The load study for a new building is easier to
achieve. Understanding the actual building load so
that equipment can be right-sized is critical. This
allows the software to sequence the equipment so
it can operate most efficiently for longer periods of
time throughout the year, thus providing a greater
overall percent reduction in energy usage.
Waterside economizer
Waterside economizer uses the evaporative cooling capacity of the cooling tower to produce cold
water that is exchanged through a heat exchanger
to provide chilled water that offsets the need for
mechanical cooling. In climate zones without sigwww.csemag.com
CASE STUDY: Hospital heat recovery chiller
ing demand so that there is no
or this new 875,000-squarewaste heat or cooling produced.
foot replacement hospital, a
In addition, the heat recovery chillheat recovery chiller was inteer was piped and valved so that it
grated into the design of the chillcould operate both in series and in
er plant and sized to meet the
parallel with the primary electric
400-ton process cooling load. This
water-cooled centrifugal chillers.
capacity includes the operating
During winter operation, the
suite air handling unit cooling coils,
heat recovery chiller operates in
which allows the main chilled water
parallel with the primary chillers to
plant to be taken offline during the
satisfy the cooling demand. During
heating season.
summer operation, the heat recovThe heat recovery chiller is also
ery chiller operates in series with
capable of providing approximatethe primary chillers and thermally
ly 6,200 MBH of heating. This heating capacity exceeds the calculated Figure 3: This shows the heat recovery follows the heating demand.
The integration of a heat recovhot water terminal reheat demand chiller’s series/parallel piping arrangeery chiller into the central utility
in the summer, which means that ment. Courtesy: SmithGroup
plant lowers the dependence on
the boiler plant can be taken
offline during the cooling season. During the shoulder fossil fuels as clean electrical energy sources become
more prevalent and reduces the overall energy use
months, all central plant equipment will be operating.
The goal was to maximize the loading on the heat of the facility. Figure 4 describes the interaction of
recovery chiller due to its superior coefficient of per- the hot water heating plant, the heat recovery chillformance relative to decoupled chilled water and hot er cooling, the heat recovery chiller heating and the
water production. It was important to study the con- central chilled water plant during a typical shoulder
trol strategies at different conditions throughout the season day. The study of how this equipment will work
year. It is critical to design the main chiller plant with together during different operating conditions helps to
a high turndown capability so the plant can slow- develop the chiller plant control strategy and helps to
ly stage on while the heat recovery chiller maintains define the heat recovery chiller capacity.
The central utility plant for this hospital includes:
max cooling capacity when the total cooling load
begins to exceed the capacity of the heat recovery
• Six 8,000 MBH hot water heating boilers.
chiller (see Figure 3).
• Three 1,200-ton centrifugal chillers.
The packaged chiller controls allow the heat recov• One 482-ton heat recovery chiller.
ery chiller to satisfy the lowest of the heating or coolFigure 4: This
describes the interaction of the hot
water heating plant,
the heat recovery
chiller cooling,
the heat recovery
chiller heating and
the central chilled
water plant during a
typical shoulder season day. Courtesy:
consulting-specifying engineer
June 2020
nificant year-round high relative humidity, integrated waterside economizers can provide significant
energy savings by reducing the hours of operation
of chillers and by reducing the chiller load during
hours when 100% economizer isn’t possible.
The benefits of waterside economizers increase
with warmer chilled water supply temperatures, so
they pair especially well with hydronic systems such
There are several other strategies
that can be deployed to increase waterside economizer hours, reduce chiller
hours and possibly eliminate the need
for compressor cooling all together.
as radiant cooling, chilled beams and dedicated outdoor air system fan coil boxes, where air-side economizers are either not applicable or not feasible.
In other scenarios where traditional air-side
economizers are not ideal, such as climate zones
where an outside air economizer would introduce
too much dehumidification load or mission critical data centers where excessive outside air may
reduce the interior relative humidity too low, waterside economizers may be used to achieve significant
savings. Like all heating, ventilation and air conditioning system selections, it is important to understand the impact on all systems together, including
building enclosure, building massing, load profile
and occupant comfort expectations.
When waterside economizers are optimized
alongside each of these influencing systems, then
the potential benefits of waterside economizing
only increase (see Figure 2).
Traditional chilled water systems
Traditional chilled water systems producing 42°F
to 44°F chilled water will be limited in how many
hours they can take advantage of 100% waterside
economizer, especially when the engineer has specified a traditional cooling tower approach of 6°F to
7°F and required a plate and frame heat exchanger
with its 1°F to 2°F approach. This may leave the system able to operate at 100% economizer mode only
when wetbulb temperatures are at or below 36°F. A
traditional chilled water design approach in a building with high internal loads, such as an office building results in a low percentage of operating hours
that can be used for 100% economizer mode.
Although cooling tower cost goes up as the cooling tower approach decreases, each project team
should evaluate the cost benefit analysis to select
June 2020
close approach towers in the 2°F to 3°F range. This
increases the number of full economizer hours and
will further reduce the operating hours on the chillers and their corresponding energy use.
Mild temperature
chilled water systems
The real beauty of waterside economizers is on
display when they are paired with mild temperature chilled water systems. Instead of operating in
the 42°F to 44°F range, these systems tend to operate around 54°F to 58°F and supply radiant cooling systems, chilled beams or sensible only DOAS
fan coil boxes. Typically, these systems are working
in parallel with a DOAS system, which is handling
dehumidification with a direct expansion system or
standalone low-temperature chilled water coil supplied by a separate system.
As radiant systems, chilled beams and DOAS fan
coil boxes are designed for sensible cooling only,
they do not require low-temperature chilled water
and in fact don’t want chilled supply water temperatures which could result in condensation. So,
the elevated chilled water temperatures are ideal.
These increased supply water temperatures greatly increase the available hours for 100% waterside
economizer, showing economizer hours with a traditional approach cooling tower.
When you pair these systems with close
approach towers, you can see dramatic increase
in hours of full economizer mode. This brings the
total hours available for full economizer up over
80% of hours in Oakland, Calif.
Advanced waterside
economizer strategies
Besides selecting close approach towers, there
are several other strategies that can be deployed to
increase waterside economizer hours, reduce chiller
hours and possibly eliminate the need for compressor cooling all together. The first strategy is a chilled
water supply temperature reset control sequence
(ASHRAE 90.1-2019 Part, which should be
deployed on all waterside economizer systems.
In this scenario, the BMS monitors all cooling
valve positions. As soon as all chilled water valves
are less than 100% open, the BMS will linearly reset
the chilled water supply temperature upward until
the first valve must open 100% to satisfy the local
load. This can result in significant increased hours
with full economizer, especially in buildings with
high-performance enclosures and most buildings in
the shoulder seasons, when envelope loads are low.
Additionally, waterside economizer systems pair
well with thermal energy storage systems, especially mild temperature systems serving sensible only
cooling systems. Thermal energy storage systems
maximize the use of nighttime charging of the storwww.csemag.com
age tanks when outside wetbulb temperatures are at
their lowest, allowing for low cost chilled water production using nighttime off-peak power rates. If the
building has been designed to be a low-load, highperformance building, teams may be able to install
sufficient thermal storage to remove the need for
chillers altogether to meet the sensible building load.
Although the typical thermal storage medium is
water (or ice for low-temperature chilled water systems), recent research from the University of California, Berkeley’s Center for the Built Environment
has shown significant flexibility in mass-radiant
cooling systems to support load shifting through
controls manipulation alone and the inherent thermal mass of the slab. That flexibility has shown
that in some instances, active cooling into the slab
may shift upward of 12 hours separation from the
time of peak load in the space, while still keeping
the space operative temperature with the comfort
range expected by ASHRAE Standard 55: Thermal
Environmental Conditions for Human Occupancy.
Adding ceiling fans into the space, which with
modest air-speeds support thermal comfort even
up to 78°F room setpoints may increase that load
shifting flexibility even more, potentially allowing
100% of cooling hours to be met with full waterside
Heat recovery chillers
Heat recovery chillers can provide energy savings in facilities where there is a need for simultaneous heating and cooling, such as hospitality and
health care facilities. While six-pipe, dual-condenser heat recovery chillers are available, this discussion focuses on four-pipe, single-condenser heat
recovery chiller applications.
A standard water-cooled chiller operates to
remove heat from a chilled water loop and transfers
that heat into a condenser water loop. The heat is
then rejected from the condenser water loop to the
outdoors by a cooling tower. The waste heat that is
normally rejected to the outdoors can be recovered
and used in applications where heat is required,
such as heating domestic water or terminal reheat.
A heat recovery chiller is designed to provide
both heating hot water and chilled water. The waste
heat that is removed from the chilled water loop is
captured in a hot water loop that is used for heating.
When specifying a heat recovery chiller, it is important to consider the baseline heating and cooling
load profiles of the building to properly size the
heat recovery chiller.
When considering a heat recovery application,
always select the lowest practical heating temperature to meet the needs. Space heating systems are
normally designed at 140°F supply water temperature. Typically, heat recovery chillers are designed
to provide hot water for space heating at 105°F to
110°F. To accommodate this lower water temperature, terminal reheat systems can be designed to
operate with 110°F water when specified with higher capacity, multiple row heating coils.
Another application such as service water preheating normally uses heat recovery water temperatures of 85°F to 95°F. Selecting the lowest practical
heating temperature reduces the chiller lift and
results in the chiller operating more efficiently.
Heat recovery chillers can be very effective
in health care facilities. Hospitals typically have
large variable air volume air handling units that
provide cooling and dehumidification and deliver air at a temperature of approximately 55°F. To
help with infection control, clinical spaces within health care facilities are required to have minimum air change rates. As a result of minimum air
change rates, rooms are often provided with more
air than is needed for cooling the space. To counter this overcooling, terminal reheat is required. As
a result, reheat energy has historically been one of
the largest end uses of energy in a hospital, representing 25% to 30% of the total annual energy usage
depending on the climate zone.
A heat recovery chiller that is sized to provide the
terminal reheat load during summer operation can
offset the reheat load entirely while also providing
chilled water and reducing the demand on the main
chiller plant. During winter operation, the heat recovery chiller can operate to meet the process cooling
loads of the hospital while also providing hot water to
reduce the demand on the boiler plant. Essentially, the
building owner gets heat energy at virtually no cost
because it is a byproduct of the cooling process.
Chiller plant design can have a significant
impact on the ongoing operating costs of a building. Strategies such as chiller plant optimization,
water side economizer and heat recovery chillers can create positive results by improving overall
plant efficiency and reducing energy costs. The type
of building, climate and load profile are contributing factors into whether one or all of those strategies should be considered. cse
Scott Battles is an associate with SmithGroup. Battles works in a wide array of markets including academic, life sciences, pharmaceutical and public sector
work with a focus on health care.
Jonathan Hulke is an associate with SmithGroup.
Hulke specializes in creating condition reports of
existing building systems, building HVAC energy audits and life cycle cost analysis of HVAC
Stet Sanborn is a principal with SmithGroup. Sanborn specializes in net zero energy and net zero carbon design.
consulting-specifying engineer
June 2020
By Paul Erickson, LEED AP BD+C, Affiliated Engineers Inc., Madison, Wis.
Green, zero energy and
energy-efficient buildings
How do you design an energy-efficient building? Learn about codes
and standards, building energy terminology and design goals
larifying owners’ understanding of performance-improving goals establishes a
unifying basis for green building project options, processes and outcomes.
Sustainable thinking and building
practices have evolved so rapidly that owners often
struggle to assign distinctions between characterizations of “energy-efficient,” “green,” and “net zero.”
However, rather than thinking in terms of differences in establishing project goals and identifying how to meet them, a more useful
approach plots such designations on
a continuum that equally describes
the expanding imperative to integrate
• Understand distinctions between
systems. With this understanding,
commonly cited performanceowners can better anticipate evolving
improving goals and how
user expectations and code requireto leverage for setting and
achieving desired project targets.
ments and more fully capitalize on
the potential of a higher-performing
• Know about the rising bar of
green building rating systems,
building. The prevalence of specific
standards and codes.
technologies and strategies align with
• Learn about the trajectory of
specific points over this spectrum, all
green buildings and sustainability
subject to the specifics of program,
in the built environment.
scale, site and climate to succeed.
Energy: the start
The adage goes: “code represents the worst possible building that can legally be built.” Fifty years
ago, that seemed perfectly sufficient when it came
to energy usage. Though the oil embargo of the
1970s compelled the design industry to consider
energy, there was no national policy at the time.
That event started the industry on a trajectory that
finds us in a much different place now.
Prompted by the sense of vulnerability that the
embargo wrought, ASHRAE developed a standard for the energy-efficient design of buildings,
Standard 90, published in 1975. As with many
building industry standards, the intent was to create parameters that states could readily adopt as
June 2020
consulting-specifying engineer
code. The U.S. began to see sporadic implementation of the standard and its periodic revisions.
Responding to the rate of change in energy technologies and prices, ASHRAE initiated a cycle of
triennial review and revision in 2001, renaming
the code ASHRAE Standard 90.1: Energy Standard for Buildings Except Low-Rise Residential
Buildings. ASHRAE subsequently issued separate
standards specific to low-rise residential buildings
(90.2) and data centers (90.4).
Throughout its first two decades, Standard 90.1
has set a bar for energy-efficient design, continually striving to make energy improvements across
all aspects of the envelope, mechanical, electrical
and plumbing systems. Improving efficiency across
these systems is recognized to impact various building sectors/types differently, though the standard
yields portfolio-level savings and has been on a trajectory of constant improvement (see Figure 1).
With state and local entities adopting a patchwork of standard versions, applying revisions sluggishly and issuing a wide variety of exceptions
at the same time as the standard’s requirements
become ever steeper, the standard regularly outpaces code to varying degrees nationwide. The same
has been true with the International Energy Conservation Code, the model energy code maintained
by the International Code Commission.
First released in 2000 and revised every three
years through a public review and consensus process, it too found sporadic adoption of revisions.
Figure 2 shows the status of energy code adoption in 2018, revealing how varied commitments
to Standard 90.1 and IECC and their updates have
been. A relatively current accounting of state-bystate adoption can be found here.
Energy efficiency continues to be a focus of
standards development, code adoption and utility
incentive programs, though what was once seen as
“high efficiency” — such technologies and stratewww.csemag.com
ASHRAE 90.1 energy-efficiency improvements
Figure 1: This shows the percent energy-efficiency improvement of ASHRAE Standard 90.1, as
determined by an ASHRAE/Department of Energy quantitative analysis. Courtesy: Affiliated Engineers Inc.
gies as premium pump and fan motors, variable
frequency drives, variable air volume, condensing boilers, economizers, temperature setbacks and
LED lighting — now register as the norm.
There is still rich opportunity for energy savings in retrofitting buildings and in new design.
ASHRAE developed Advanced Energy Design
Guides to support the design and operations community, releasing progressively more aggressive
versions for a variety of building types. Originally targeting 30% savings beyond ASHRAE 90.12004, then 50%, it recently released AEDGs for
zero energy design.
ASHRAE also developed Standard 100: Energy
Efficiency in Existing Buildings to provide “greater guidance and a more comprehensive approach
to the retrofit of existing buildings for increased
energy efficiency.”
The newest ASHRAE guideline, ASHRAE
Guideline 36-2018: High-Performance Sequences
of Operation for HVAC Systems, provides uniform
sequences of operation for heating, ventilation
and air conditioning systems that are intended to:
maximize the systems’ energy efficiency and performance, provide control stability and allow for
real-time fault detection and diagnostics.
Benchmarking of existing buildings has been
driven by legislation in select cities across the country, including Seattle and New York City, leading
to improved transparency about the performance
of building stock. Publicly available data sets make
it easier for lessors or potential buyers to understand operational costs. Having data available to
Benchmarking of existing buildings has been
driven by legislation in select cities across the
country, leading to improved transparency
about the performance of building stock.
owners can readily facilitate assessment and implementation of energy savings measures that may be
Beyond their communities, establishing both
the political and logistical pathways for implementing benchmarking serves to provide a model and
associated resources that allow other municipalities
to more readily pursue and adopt similar requirements. Building energy scoring programs like EnergyStar, BuildingEQ and the Commercial Building
Energy Asset Scoring Tool seek to leverage transparency and score buildings for prospective tenants
and owners to be able to understand anticipated energy performance and costs. The city of San
Francisco not only requires all commercial buildings to submit energy usage data annually in its
Ordinance 0017-11, but also that owners will conduct energy audits every five years.
Energy and green buildings
Green buildings and sustainability in the built
environment have enjoyed significant momentum
and adoption in the past 10 to 15 years. The prominent mainstreaming of sustainability and fairly
consulting-specifying engineer
June 2020
Figure 2: Stateby-state status
of energy code
adoption is
shown as of
2018. Courtesy: Affiliated
Engineers Inc.
With green building rating systems
there has long been the risk of conflating
high levels of green performance with a
requisite high level of energy efficiency.
widespread recognition of green buildings might
obscure what are in fact 30-year roots to the green
building movement. With the formation of the
AIA Committee on the Environment in 1989, the
founding of the U.S. Green Building Council in
1993 and the “Greening of the White House” in
1993, a nascent movement began to take shape in
the United States.
Across the Atlantic, the U.K.-based BREEAM
rating system was launching around this same
time. Its first version, launched in 1990, assessed
new office buildings. Energy was a major focus of
these and other early green efforts — so much so
that the USGBC emphasized energy in the title of
its LEED rating system.
Launched in 1998, the first version of LEED
not only emphasized the importance of energy
efficiency, but also established a broader understanding of and advocacy for environmental
resource stewardship. Site, water, energy, materials and indoor environmental quality categorically
gave breadth to the concerns and impacts tied to
June 2020
the built environment. These raised such issues as
mass transit, native ecosystems, stormwater management, refrigerant impact on the ozone, global
warming, material reuse, local purchasing, indoor
air quality and occupant comfort.
Such breadth was an early challenge to design
teams and the owners they were serving, while
energy’s “head start” established a level of familiarity as well as defined metrics for assessing opportunities and their related economics. Whether for
that association or the gathering focus at the time
that most energy was tied to fossil fuels, energy
efficiency became synonymous with green buildings to many.
There was an expectation that the greener the
building, the more energy efficient it must be and
critics of LEED often pointed to underwhelming
— or what was seen to be deficient — energy performance. In 2008, the New Buildings Institute
published a report funded by the USGBC and the
U.S. Environmental Protection Agency evaluating
the energy performance of LEED buildings. The
report revealed that many were performing worse
than anticipated (modeled) and some were even
performing below code.
With green building rating systems there has
long been the risk of conflating high levels of green
performance with a requisite high level of energy
efficiency, but the reality is that energy usage is just
one of the many metrics of a broader set of values
and strategies to reduce environmental impact and
improve the built environment. While some owners and project designers found it easier initially to
Standards evolution
focus on energy, something more quantitative and
familiar, others prioritized other metrics and categories as reflecting their values and objectives.
Thus, a “green building” becomes something
not as easily compared one to another, even when
a scoring rubric facilitates point tallies resulting in
tiers of outcomes (i.e., LEED certified, silver, gold
and platinum; 1 to 4 of Green Building Initiative’s
Green Globes).
The growing recognition of this dynamic led
many entities to begin specifying energy, water
and other targets to ensure that the desired performance of within one or multiple categories would
be reflected in the metrics (outcomes) of the green
building rating systems. This effective prioritization of credits for each owner organization has been
intended to reflect their values. Energy has been
one of the most common examples, with many colleges and universities, certain states and the federal government setting targets to try to ensure that
a high level of energy efficiency is indeed a major
attribute of their own green buildings.
One advantage of this and even of the prerequisite energy performance targets of the rating systems themselves (i.e., 5%, 10% better), has been
that in many cases, projects were pushed to go
beyond code. Because the rating system versions
were continually changing to subsequent versions
of Standard 90.1, many projects were pressed to
exceed what would have been code-minimum in
their respective states, whether based on Standard
90.1 or IECC.
“Energy efficiency” continues to have meaning, at least as something better than code, but the
evolved expectations of many in the design community and beyond have set the target for energy savings much, much higher, such that energy efficient
simply doesn’t fully connote what’s expected. That
said, tangible benefits the industry has seen from
energy being an integral component, if not the driver, in green building design include:
• Energy modeling tools (whole building,
single zone, façade).
• Aa new vocabulary around energy usage metrics and target-setting that facilitates change
and benefits other rating system categories.
• Promoting life cycle cost analysis, life cycle
analysis and carbon accounting.
• Renewables positioned as tangible and
• Integrated decision making for energy,
heating/cooling loads, daylighting, occupant
Figure 3: Evolving standards requirements have been accompanied
over time by an expanding awareness and inclusion of related causes
and further effects. Courtesy: Affiliated Engineers Inc.
The energy bar has risen
The constant revisions to green building rating systems, standards and codes continue to
reflect that the building industry has progressed
significantly in adopting aspects whose benefits
initially seemed more qualitative and subjective.
While these aspects of green buildings were a bit
slower to gain owner buy-in and categories that
were more quantitative were more readily adopted in the early days, project teams today reach
deeper and deeper in all categories from where
the industry was 30 years ago, with new credits
and refined point relationships continually challenging design and construction professionals.
In addition, broader thinking about sustainability has led to related rating system categories and
credits that reflect a broadening definition and
understanding of green buildings and sustainability (see Figure 3).
Energy has been the category leading by example when it comes to deepening the goals. What
was once a seemingly far-off point on the Standard
90.1 energy savings trajectory — the point representing ultra-low building energy use intensity
that could effectively be offset by on-site renewable energy — has come to be seen as believable,
feasible and even cost-effective in many climates
for numerous building types. A zero energy building, as defined by the Department of Energy, is:
consulting-specifying engineer
June 2020
Figure 4: Consolidating five existing
locations, the new
home of the California Air Resource
Board will be the
world’s largest
zero energy facility of its type as
well as one of the
largest and most
advanced vehicle
emissions testing
and research facilities in the world.
Courtesy: ZGF
“An energy-efficient building where, on a source
energy basis, the actual annual delivered energy is
less than or equal to the on-site renewable exported energy.”
This has become the common go-to goal for
owners and design teams focused on meaningful
energy efficiency. Projects now seek to push beyond
annual zero energy performance, ideally generating
more power over the course of the year than needed, seeking to be net-positive and “restorative” to
our environment.
The Living Building Challenge is one rating system example driving this, now requiring 105% of
anticipated energy use to be offset by renewables.
Zero energy has been successfully achieved to such
a degree that ASHRAE has been able to develop
Zero Energy Design Guides for K-12 schools and
small- to medium-sized office buildings. The state
of California has been a leader in driving zero energy facilities with the California Energy Efficiency Strategic Plan, which outlines the goals for the
development of ZEBs, using a slightly different terminology common in the buildings industry, zero
net energy buildings. These include:
• All new residential construction will
be ZNE by 2020.
• All new commercial construction will
be ZNE by 2030.
• 50% of commercial buildings will
be retrofit to ZNE by 2030.
• 50% of new major renovations of state
buildings will be ZNE by 2025.
The 2019 California Building Standards Code
(Cal. Code Regs., Title 24) code revision, which
June 2020
goes into effect in 2020, works to align with the
plan, establishing the criteria for new residential
design such that it will deliver zero net electricity. The code does not currently require all-electric
design nor offsets for fossil fuel consumption.
On the commercial building side, Executive
Order (EO) B-18-12 issued in 2017 and subsequent
administrative guidance directs all California buildings beginning design after 2025 to be ZNE and at
least 50% beginning design after 2020 to meet the
goal. Subsequently, determining that the market is
already capable of cost effectively delivering ZNE
buildings, the state has accelerated the adoption by
targeting ZNE in the requests for proposals it has
issued for the past couple of years.
Though California may be leading the way in
terms of energy code, there are examples of projects
across the country demonstrating that zero energy is possible. The New Buildings Institute hosts
an online database showing certified and emerging
ZEBs. Many advocacy groups, cities and states are
considering how to improve codes and/or voluntary
paths toward widespread adoption of ZEBs.
The inextricable link between energy and fossil fuels throughout much of the country has been
increasingly recognized by project goals seeking
to be carbon neutral or carbon positive. To more
effectively decarbonize in areas with cleaner grid
emissions factors and rapidly expanding renewable
content, some projects are now seeking to change
over to electricity-based heating in lieu of natural
gas or fuel oil.
Project teams are working with owners to also
identify electrification strategies for such internal
processes as cooking, humidification, sterilization
and other intensive activities traditionally served
by fossil fuel boilers. In some cases, new fossil fuel
bans are aiding or even driving factors in these new
Design professionals are also seeking to move
beyond simple, annualized utility grid emissions
factors toward an hourly or real-time understanding such that design and operational decisions
can take carbon into account more effectively and
meaningfully. Thermal energy storage and electric
battery storage become tools for managing the time
of grid-sourced electrical energy use and thus the
carbon content of energy used. These are not energy-efficiency strategies, but they do align with the
fundamental concerns of energy efficiency.
Efficient water use
Energy and efficient use of it has found a friend in
water and the growing understanding of their mutual
association in electric utilities and building systems.
Termed the water-energy nexus, a growing body of
knowledge is revealing where energy and water can
be traded off. For example, an air-cooled chiller will
typically be less energy efficient than a water-cooled
chiller, but significant water and chemical use savings to a project exist when using the former. The
value of each resource should be assigned to determine the best path forward for each project.
Attention to water lags energy by about two
decades but is catching up rapidly. New standards
and codes are providing a basis for increasing water
efficiency and reuse for plumbing, irrigation and
HVAC systems. Among these are ASHRAE 191P
and IAPMO Water Efficiency Standard along with
the water efficiency components of CALGreen and
ASHRAE 189.1: Standard for the Design of HighPerformance Green Buildings Except Low-Rise
Residential Buildings included as part of the International Green Construction Code.
The cost of water varies greatly from community to community as infrastructure profiles, scarcity, subsidies and quality vary greatly with a cost
range of as much as 30-to-1. This has led to uneven
pursuit of water efficiency as the payback varies
so much. Cities such as San Antonio have adopted
water reuse measures where cooling coil condensate
must be captured from certain facilities and reused.
The holistic view of water, blending site and building in conjunction with the water-energy nexus, is
serving to propel towards greater savings and more
aggressive targets, including net zero water.
As in the case of water, consideration of materials follows the path of energy to greater awareness and growing expectations. Much of the focus
to date has been on toxicity (thoughtfully considering sourcing, manufacturing, end use implications),
impact on indoor air quality and distance of manufacturing from projects (considering local/regional community economics as well as transportation’s
environmental impacts).
The immediate concern of climate change has
not only turned the energy conversation to carbon
emissions, but also embedded (or embodied) carbon of materials is seeing newly heightened attention. The linking of the embodied and operational
carbon creates a fuller picture for informed, metric-based decision making. This can be seen in the
emerging focus on embodied carbon and greater
accountability with the LEED v4 life cycle assessment credit.
The AIA 2030 Commitment benchmarking
database update is expected to include tracking of
embodied carbon. For now, the majority of the focus
is on architectural and structural systems and their
materials given available embodied emissions data.
Eventually the embodied carbon of mechanical, electrical, plumbing and other nonstructural engineered
systems will need to be accounted for and tracked.
The International Living Future Institute
includes in its Living Building Challenge requirements for tracking and offsetting the embodied
carbon from construction. It also now provides a
Zero Carbon Certification that includes both the
operational and embodied carbon for projects,
establishing requirements and metrics to drive the
conversation forward.
Holistic standards and rating systems are
encouraging this sort of deep, integrated thinking,
particularly if owners are compelled to continue to
score higher marks and/or reflect their own deepening and evolving sustainability values.
A great example of this can be seen in California’s 2018 stipulated sum design competition
request for proposals, for a new 383,000-squarefoot California Air Resources Board testing and
research facility (see Figure 4). Goals for the project
represented the state of the imminent future across
building performance categories: zero energy onsite, minimum of 3.5 megawatts on-site photovoltaics, minimum of 1.5 megawatt-hours of battery
storage, minimum of nearly 100 electric vehicle
chargers, an energy dashboard, LEED v4 Platinum
and a minimum of 30 credits in CALGreen Tier 2.
Within the broader target-setting for LEED and
CALGreen, credit categories and minimum point
thresholds were mandated in many instances to
establish more granular goals. This occurred for
water, for refrigerants, for materials and for indoor
environmental quality. With a mission for improving air quality internal and external to the building, CARB is leveraging holistic and integrated
sustainability to ensure that its green building will
reflect its values, both in quantitative and qualitative areas. cse
Paul Erickson is a principal and the building performance market leader at Affiliated Engineers Inc.
He draws on his knowledge of performance modeling
tools and project experience in the science and technology, health care and higher education markets.
consulting-specifying engineer
June 2020
How is COVID-19 affecting
retail, restaurants?
With consumers frequently enjoying delivered meals and shopping
for goods online, brick-and-mortar restaurants and retail structures need
to be more advanced than ever to compete
CSE: What’s the current trend
in retail, restaurant and mixed-use
Scott Garrison: Lighting that is highly
integrated with the architecture and interior design is a definite trend that we have
witnessed for destination dining. Modern
design with strong graphics, clean architectural design and well thought out lighting has steadily progressed.
Furthermore, lighting design has
gained prominence as an important tool
in enticing both retail and restaurant tenants to rent space in mixed-use buildings.
Using lighting to make a building’s façade
attractive at night offers a marquee location that the retail and restaurant tenants
perceive as valuable in creating a destination space. This has proven a successful
technique in downtown Detroit.
Jessica Iversen: Many retailers and
mixed-use facilities are moving toward
a focus on additional services and experiences that cannot be achieved via the
internet and online shopping. This could
be a reconfiguring of product areas or an
emphasis on spaces that provide other
services, like classes or product maintenance/servicing. Restaurants are finding
ways to more seamlessly leverage outside
delivery services, as these continue to
change the face of an industry.
Bradley D. Williams: It’s an interesting time to address this question. The
thought process for these market sectors
is changing in response to recent COVID19 pandemic concerns. Because in the
more expensive real estate markets the
rental cost per square foot and energy
prices drive space and system efficiency
decisions, an interesting dichotomy will
develop between the need for efficient use
of space and the need to increase ventilation and filtration for these spaces.
Owners will be looking for increased
occupant spacing (but not necessarily
increased space), while being required to
operate systems in a less efficient manner
using increased ventilation and higher
levels of filtration to protect their spaces.
This will be a challenge for our industry
moving forward.
Jason Wollum: A current trend
that we are seeing is for a brand to create unique customer experiences in the
physical space that connects the customer and the brand. This is being done
through interactive technology, through
customizable experiences and customizable products and through great customer service that helps tell the brand’s story
Scott Garrison
Peter Basso Associates
Troy, Mich.
June 2020
consulting-specifying engineer
that helps to express what a brand’s values are and helps drive customer loyalty.
Today, it’s less about a customer walking
into a store and buying a product that
they need and more about the customer
going into a store, having a great experience and getting exactly the product that
they want from the brand that they love.
CSE: How is the growth of immediate-delivery services impacting
retail, restaurant and mixed-use
Wollum: These services are impacting the way customers define convenience and are creating a new standard
that all retailers are being judged by. It is
only one of the items that people use to
evaluate brands they like, but it is vitally
important. Convenience is a major driver
that connects people with a brand.
Iversen: In the restaurant industry, companies focused specifically on
delivery-only kitchens are becoming
more common. These facilities, known
as ghost kitchens or cloud kitchens, can
house multiple restaurants under one
roof, with no dining areas. The focus is
entirely on delivery services, with multiple kitchens grouped in one building.
Jessica Iversen,
Bradley D.
Williams, PE
Seattle Office Leader |
Project Engineer
RTM Engineering
Vice President
Bala Consulting
New York City
Figure 1: Henderson Engineers
worked on the Nike flagship store
in New York City, which involved
converting an older building with an
all-glass façade. Challenges on the
unique project included selecting and
designing an HVAC system through
performance modeling. Throughout
the grand entry, the power and data
distribution and lighting control
systems were designed to facilitate
simpler space reconfigurations. One
of the primary goals was a focus on
adaptability, allowing the space to
easily transform with the evolving
taste of the consumer and city trends.
The result was a one-of-a-kind retail
experience that we’re all incredibly
proud of. Photos: Mary Blevins/Henderson Engineers
These facilities create their own engineering challenges, with more cooking areas, larger coolers and freezers
and often a need for greater flexibility than you would find in a standalone
Garrison: We live in a world where
one-click shopping and next day (or in
some cases same day) delivery has influenced expectations in just about everything we do. Many restaurant and retail
clients, particularly specialty and boutique retailers, who do not regularly
engage in design and construction projects, have these expectations. Although
advanced software and instantaneous
information sharing among design team
members and the clients can speed up
the process, it still takes time to properly
develop the design, coordinate amongst
disciplines, solicit bids, procure materials and construct a space. The design
and construction teams must skillfully
manage these expectations.
Once the client makes a financial commitment to develop a space,
they want the space functional and
generating revenue as soon as possiJason Wollum,
Retail Practice
Director | Senior Vice
Henderson Engineers
Kansas City
Touchless checkout will become much more
prevalent, along with the use of smart technologies
to maximize employee time spent out on the
retail floor. —Jessica Iversen
ble. Many times, these financial goals
and associated timing are determined
before consulting with a design team
or a contractor, further reinforcing the
CSE: In your opinion, how do you
think COVID-19 will change the
future design of retail, restaurant
and mixed-use facilities?
Iversen: Avoiding unnecessary contact will be a major design consideration
moving forward. Touchless checkout will become much more prevalent,
along with the use of smart technologies to maximize employee time spent
out on the retail floor. Dining areas in
restaurants will need to be modified to
accommodate required social distancing
measures. Designers and owners will also
be more cognizant of mechanical ventilation standards and we may see these
becoming more stringent.
Williams: COVID-19 will absolutely change the face of design moving forward. To support the well-being
of occupants, we must consider spread-
ing out our work spaces and increasing ventilation rates. Filtration of the
air entering spaces will be paramount
to the engineer’s basis of design, where
emerging technologies may play a part.
Technologies such as ultraviolet-C light,
bi-polar ionization, high-efficiency particulate air filtration and perhaps other
new technologies will be studied for
their immediate impact and implementation ability. As engineers we have spent
a large amount of time exploring how to
densify spaces and save energy, while the
“new normal” may work counter to some
of these efforts. cse
M More
Read more online and watch videos on this
topic at www.csemag.com:
• Automation, controls and technology.
• Codes and standards.
• Electrical and power systems.
• Energy efficiency and sustainability.
• Fire and life safety systems.
consulting-specifying engineer
June 2020
Now, more than ever, engineering innovation plays a
vital role in the vitality of industrial manufacturing.
We invite you to explore the profiles on the
following pages and celebrate the success stories
of these participating manufacturing innovators:
ABB Motors
and Mechanical
Meltric Corporation
C&C Power
Cyber Sciences
Technologies, Inc.
Data Aire Inc.
View the 2020 profiles and videos at:
ABB provides solutions.
ABB provides solutions for efficient production, safe and reliable operations,
and digital remote condition monitoring across most industrial plant equipment
and systems.
ABB Ability™ Smart
Sensors: Always
know how your
equipment is feeling
The ABB Ability Smart
Sensor monitors the health of your low voltage motors, bearings, gear reducers and pumps by
gathering data on vibration, temperature and other parameters that can be used to gain meaningful
information on condition and performance, enabling users to identify inefficiencies within their system
and to reduce risks related to operation and maintenance. Maintenance can now be planned according to actual needs rather than based on generic schedules. This extends equipment lifetime, cuts
maintenance costs, and reduces or prevents unplanned downtime due to breakdowns.
EC Titanium: High performance.
Flexible solution.
As energy regulations require higher total system
efficiency, achieve IE5 efficiency in smaller spaces
and with less maintenance by relying on the
Baldor-Reliance® EC Titanium™ integrated motor
drive. The EC Titanium is a highly efficient integrated
motor drive that combines synchronous reluctance
and permanent magnet technologies for a sustainable,
wirelessly connected solution that improves your bottom
line. This sustainable, IE5 solution runs out of the box,
minimizes installation costs and increases facility safety.
NXR Motors
Buying low and medium voltage motors has never been
easier. ABB’s N-series general purpose motors combine
cost-efficient standardized designs and short lead times
with safety, productivity, energy efficiency and reliability.
Totally enclosed fan cooled motors, type NXR, General
purpose above NEMA motors fit most applications where
a highly customized motor is not needed.
ABB is the leading US marketer, designer, manufacturer and service provider
of ABB and Baldor-Reliance® industrial electric motors and Dodge®
mechanical power transmission products. With a long rich history dating
back to 1878, the US ABB business is supported with manufacturing, R&D and
support offices in more than 15 locations in Arkansas, Oklahoma, Missouri,
Mississippi, Tennessee, Georgia, North Carolina and South Carolina.
input #7 at www.csemag.com/information
AERCO Benchmark 4000/5000N:
Big Performance, Small Size
AERCO’s Benchmark Platinum 4000 and 5000N commercial condensing boilers
improve operating efficiency and increase energy savings, in the industry’s
smallest 4000/5000 MBH footprint. Incorporating a durable 439 stainless steel,
fire-tube heat exchanger and advanced technologies, the boilers easily fit in
retrofit and new construction requiring one or multiple 4000 or 5000 MBH boilers.
AERtrim® Patented O2 Trim Technology
AERCO’s innovative, patented AERtrim monitors the actual conditions of the
Benchmark Platinum 4000/5000N and self-adjusts its combustion process to
optimize O2 levels. The result is improved uptime reliability, lower emissions,
reduced operating and maintenance costs, and increased efficiency, including
an additional 1%-2% in seasonal efficiency gain.
Edge® Controller and Mobile App
AERCO’s Edge Controller helps save time and money while streamlining and
simplifying operation and maintenance. It delivers many industry firsts, including
EZ setup, combination plant setup through manager and Combustion
Calibration Assist. Edge Controller also allows users to
submit service forms directly from the Edge Mobile App.
The Edge Mobile App improves boiler configuration by enabling full unit setup
and control with enhanced diagnostics and configuration capabilities. It’s
available on iOS and Android.
Dual Returns
The Benchmark Platinum 4000/5000N have Dual Returns that provide
application and design flexibility while maximizing boiler efficiency by up to
an additional 7%. With Dual Returns, engineers can take full advantage of
diverse load demands specific to a site and design a customized system that
maximizes operation and performance.
onAER Predictive Maintenance
AERCO’s onAER predictive maintenance health-of-system tool enables users to
view boiler plant operation and status, track performance and efficiency, and
set and view alerts. It helps prevent unnecessary wear-and-tear of equipment
as well as premature failure and reduces unscheduled maintenance.
Compact Design
The Benchmark Platinum 4000/5000N have the industry’s smallest footprint.
They easily fit through a standard size doorway and on a freight elevator.
Industry-best Warranty
Like all Benchmark Platinum boilers, the 4000/5000N series
come with the best warranty in the industry.
Contact: sales@aerco.com; www.aerco.com; 800-526-0288
input #8 at www.csemag.com/information
Make the switch! BYPASS the lock and key
with a streamlined approach.
C&C Power is excited to announce its latest innovation in power
solutions, the Automatic Maintenance Bypass system. The system
includes patent-pending technology to safely and securely operate
your uninterrupted power supply. This new technology sets it apart
and eliminates the human variable of breaker locks and keys.
Microprocessor Controller
The innovative design eliminates user error through a microprocessor logic-driven controller to perform certain steps and
guide the user to carry out the other steps. The added logic
enhances the safety of the system while also ensuring the
function of the critical load.
Touch Screen Display
The system deploys the C&C Power touch screen HMI giving the unit
a user-friendly interface for control and system status. The graphic
display allows the maintenance team to visually navigate from UPS
power to bypassed
utility power with ease.
The controller actuates
the breaker motors to
put the breaker in the
proper state during the
transition. When user
actions are required, the controller will halt the transition
and display the required user procedure in the message
box before resuming the procedure.
HTTP Connection
An optional HTTP connection is available for remote control and status monitoring. As a result,
network communication will give the user the ability to view the bypass status from any location
with an option to control the system remotely for added security.
Multiple Configurations
This ups maintenance bypass has a three-breaker design with an optional load bank breaker. It is
available for any C&C Power freestanding UPS maintenance bypass. Features include options for
voltage, amperage, cabinet color, and AIC rating. Each cabinet is welded with heavy-gauge steel
construction and has a hinged locking front door. It comes fully assembled and tested from the factory.
C&C Power warehouses all maintenance bypass options, therefore, making our lead-time the quickest
in the industry.
The Automatic Maintenance Bypass is an ideal solution across all industries. Safeguarding your
critical data with a streamlined approach eliminates the human error found in manually switching
breakers. Learn more at: www.ccpower.com/automatic-maintenance-bypass-system/
www.ccpower.com | sales@ccpower.com | 630.617.9022
input #9 at www.csemag.com/information
Hybrid Microgrid Solutions from Caterpillar Deliver
High Performance and Compelling Return on Investment
Caterpillar offers a full portfolio of hybrid energy solutions, which are designed to help enterprises reduce fuel
expenses, lower utility bills, decrease emissions, and reduce the total cost of ownership while increasing energy
resiliency in even the most challenging environments.
Hybrid energy solutions can be combined with other innovative Cat ® solutions to address specific operational
demands and business goals. For example, industrial and commercial facilities can reduce operating costs by
implementing a Cat cogeneration system, which uses Cat gas generator sets to simultaneously provide
electricity for power needs as well as heat energy for thermal requirements.
The key for a compelling return on investment is the continuous analysis of performance, availability and costs
from every source in the system. The Cat Master Microgrid Controller (MMC) manages the flow of power to
keep loads continuously energized with high-quality
power at the lowest cost.
Customers can follow system performance by using
Cat Connect Remote Asset Monitoring, which
provides data visualization, reporting and alerts
from anywhere in the world through an easy-to-use
web interface.
Cogeneration systems are especially useful for
many types of facilities with heating or cooling needs,
including remote greenhouses and grow houses that are
offgrid or facing deferred grid extension. Caterpillar recently
supplied a leading agricultural producer in the Middle East with
a 6 MW hybrid energy solution that provides power for cooling
equipment, water chilling, mushroom cultivation and other greenhouse
processes. It is the largest single-site microgrid located in the UAE.
Caterpillar’s powerful mix of conventional and renewable power generation products is backed by global
expertise and local support, with parts and service available worldwide through the Cat authorized service
and dealer network. For more information, visit cat.com/microgrid.
Caterpillar, Inc.
Email: Electric_Power@cat.com
input #10 at www.csemag.com/information
Precision Timing Protocols and
Event Reconstruction
For years, Electrical Power Monitoring Systems (EPMS) have helped engineers manage
cost, quality, safety, and reliability of their facilities. Typically, the clocks of Intelligent
Electrical Devices (IEDs) were set over Ethernet, with accuracy of less than 1 second. In
complex electrical systems, changes can occur in a quarter-cycle or less, and so 1-msec
resolution is now commonly accepted for meaningful analysis.
Precision Time Protocol (PTP) defined in IEEE 1588 makes hi-res time synchronization
over Ethernet simple and affordable for everyone.
Sequence of Event Recorder (SER): The Black Box Recorder for Power Systems
Like an airliner’s black box recorder, Sequence of Events Recorders (SERs) record exactly
what happened and when, to 1 msec.
Precise data logged by an SER can be used for:
s Root-cause analysis, and event reconstruction after a power outage
s Verification, testing and maintenance of emergency power supply systems
s Advanced warning of slow breakers - before they fail or increase arc-flash hazard
s Documentation for electric utility, insurance, warranty, or legal purposes.
Some events cannot be anticipated and it’s even worse if they cannot be explained. SER
systems record the exact time of the initiating event (root event), as well as the cascade
of resulting events, all in chronological order. This provides the data needed to quickly
determine what happened and what action is required.
At Cyber Sciences we provide precision timing for accurate event recording, helping
minimize cost and time of recovery after a power event.
For more information visit us at: www.cyber-sciences.com
input #11 at www.csemag.com/information
Dual Cooling CRAC System
Puts Design Engineers in the Driver’s Seat
We understand how important it is for you to
proficiently calculate the load of a space and select
the system that’s best for your mission critical
clients’ budget, capacity goals and expanding
energy efficiency requirements. And while data
center power consumption has been growing, one
may think that that equates to shrinking profits.
But that’s not necessarily the case.
Become the Hero of the Story
Gone are the days of being bound by a manufacturer’s catalog. Or, at least they should be. Today,
you can ensure the highest performance at the
least amount of energy expenditure by choosing a
system that is purpose-built to your design.
Swanson Rink, an engineering firm much like yours
perhaps, partnered with Data Aire to
develop a system that exceeds strict energy
efficiency requirements in Los Angeles —
with 50% plus hours of free cooling.
CRAC System Criteria
DX coil capacity and free cooling coil have same capacity
Consistent flowrate and pressure drop between DX and ES modes
Condenser water must be controlled with a 2-way valve
Achieve a 72° supply air temp with 67° condenser water without compressor operation
DX coil can be used to trim the free cooling coil
The Solution: Dual-cooling CRAC System
Data Aire developed a system that has two cooling coils in series. One is a refrigerant coil using the compressors to make cooling. The other, a chilled water coil, uses water from the cooling tower for
cooling — referred to as the Energy Saver coil.
The system replaces high pressure drop coils with low pressure ones, has low pressure drop valves, and
internal piping that ensures the system take advantage of every gallon of water from the tower. The chilled
water coils and the condensers are oversized to provide maximum economization hours. Most importantly,
the system includes a variable speed compressor operated by a VFD, which saves energy.
The distinction between variable capacity compressors and variable speed compressors is notable; the
digital scroll is a variable capacity compressor, and can change capacity to match the load, but it doesn’t
save much energy. A variable speed compressor, on the other hand, saves a lot of energy at partial load.
And in Compressor-Assist Mode, the energy savings are significant.
The outcome: the system can provide
full-economization for 260 days —
that’s almost 72% of the year!
input #12 at www.csemag.com/information
DuctSox airflow solutions are an innovative and cost-effective fabric alternative to traditional
metal ductwork. Each system is custom engineered to meet the exact needs of the application,
along withthe additional benefits that come along with using a fabric system.
Fabric ductwork provides comfortable and efficient air dispersion while easing budgets and
installation schedules. The systems are lightweight and easy to install, while the fabric is
flexible, noise absorbing, hygienic, and condensation resistant. DuctSox systems are available
in custom colors and patterns — without the time and cost of painting.
DuctSox has over 40 years of HVAC experience. A commitment to quality and innovation has led
to the expansion of the traditional fabric offerings to include USDA approved fabrics and new
products such as fabric diffusers, and the patented SkeleCore internal framework systems.
DuctSox Corporation is headquartered in Dubuque, IA, with global manufacturing in U.S.A,
Mexico, and China. Along with local manufacturer representatives, DuctSox offers in house
engineering and design support for assistance in creating a custom solution for each job.
DuctSox are custom designed and configured to fit almost ANY space
and are ideal for a variety of environments such as:
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Phone: 866-382-8769 / 563-588-5300 | info@ductsox.com | www.ductsox.com
input #13 at www.csemag.com/information
Eaton’s Cooper PowerTM series AR-VFI transformer
maximizes safety and reliability.
By combining proven technology with innovative
design, Eaton delivers a comprehensive solution for
transformer arc flash safety.
Eaton’s Cooper Power series Arc-Reduction VFI
transformer lowers incident energy in downstream
arc flash zones, mitigating the danger posed by
power distribution equipment. Pairing our proven
vacuum fault interrupter (VFI) technology with a
microprocessor-based secondary overcurrent
protection system means anomalies are sensed
and transmitted through the integral control package
to the interrupter to fully clear the downstream
fault in less than 4 cycles.
Intelligence and reliability for the grid of the future.
Our AR-VFI transformer boasts a fully-integrated medium-voltage vacuum fault interrupter (VFI), primary/
secondary overcurrent relay protection package, system control power, and 24-hour battery backup system
that can log, send, and receive data for as long as an outage lasts.
The transformer builds time-tested secondary arc-energy reduction methods into a single fully-integrated
package. The integral arc flash reduction system uses traditional sensing, computing, and trip methods to
minimize signal proximity and total clearing time. Built, programmed, and tested in-factory the AR-VFI offers
maximized transformer safety for an unmatched price.
AR-VFI offers these important features and advantages:
• Primary and secondary 50/51
• Envirotemp FR3 fluid-filled substation
overcurrent protection
or padmount tranformer, FM or UL
listed and classified (optional)
• Self-powered, adjustable
differential protection
> Integral VFI
• Direct trip integral VFI
> Integral PRCLF for up to 50 kA
• Direct trip to local or
interrupt (recommended)
remote breakers
Primary deadfront terminations (recommended)
• Metering/monitoring capabilities
> Wired under-oil primary and secondary CTs
• Eliminates human-to-energized
> Variety of 24 Vdc differential relays with Eaton ETR standard
equipment interaction
> Integral control power and 24-hour relay battery backup
• Faster clearing time (<67 ms)
> Transformer and VFI tested per IEEE standard C57.12.00™
• Minimizes impacts of fault events
> Preprogrammed relay overcurrent settings
• Increases ease of maintenance
> Entire assembly factory tested and functionally verified prior to shipment
and asset preservation
> Standardized package offering engineered for flexibility in any application
Never compromise on safety. Learn more at Eaton.com/AR-VFI
input #14 at www.csemag.com/information
Miura Steam Boilers Take Innovation To The Next Level!
SaaS, which provides a turnkey, fully-financed solution
that meets the needs of industrial users, hospital and
schools by designing, building, operating, maintaining,
and continuously optimizing their steam generation onsite,
is an alliance of three of the leading steam companies in
the world: Miura America, Armstrong Services, and
Hartford Steam Boiler/Munich RE.
Steam-as-a-Service offers a range of benefits and
advantages that include:
Miura America celebrates 10 years in their US Manufacturing Facility/Headquarters.
Since manufacturing their first steam boiler over 60
years ago, with a focus on better efficiency, safety, and
resource conservation, Miura has become the world
leader in innovation and technology and the fastest
growing industrial steam boiler company in the North
American market. In 2019, Miura celebrated their 10th
anniversary at their Rockmart, Georgia, US manufacturing
facility and headquarters.
Engineered To Be Better.
Among the company’s many notable advances are
On-Demand Steam that produces full steam from a cold
start in less than 5 minutes, allowing users to turn boilers
on/off as needed, while saving money and conserving
resources; unique “once-through” watertube boilers
engineered with enhanced reliability; compact, modular
designs that maximize efficiency; advanced controls and
remote monitoring; and an industry-best safety record.
s A cost-effective, highly-efficient solution for
steam requirements
s No capital required, steam is delivered for a single,
monthly fee
s On-site expertise includes operations, maintenance
and administration
s Reduced downtime even during inspections with our
modular system
s Continuous optimization that increase efficiency
based on enhanced data
s A scalable, flexible solution, up or down, providing
the steam you need
s Green benefits that reduce fuel, conserve resources
and lower emissions
s A compact footprint that reduces the need for costly
space and construction
s A guaranteed solution that outsources risk back by
a world-class alliance.
In 2020, Miura and two others
launched Steam-as-a-Service.
Miura LX Series Steam Boilers
shown here in Multiple Installation.
Steam-as-a-Service Debuts.
In 2020, Miura took another giant step forward
with the introduction of Steam-as-a-Service
(SaaS), providing a cost-effective, highlyefficient solution for steam requirements
that‘s delivered for a single, monthly fee.
(Learn more about this exciting innovation
in a 4-minute video: www.youtube.com/
Phone: 678-685-0929 | us.info@miuraz.com | www.miuraboiler.com
input #15 at www.csemag.com/information
Noritz Upgrades NCC199CDV Commercial Water Heater,
Now Offering Industry-Leading 10-Year Warranty, 0.97 UEF
The re-engineered NCC199CDV also features an
industry-leading Uniform Energy Factor of 0.97 and a
now fully integrated exhaust non-return valve that
speeds and simplifies common venting for up to six
heaters without the need for additional accessories.
Because the valve is built into the heater, operational
safety is assured, and installation
time and cost are reduced.
The newly upgraded NCC199CDV
Commercial Condensing Water Heater
from Noritz America offers an industrybest, 10-year warranty on its redesigned
dual stainless steel heat exchangers.
Now produced as a unique, single-piece
structure for easier servicing, the new
heat exchangers also
incorporate substantial
improvements in
corrosion resistance
(100 percent) and
heat-shock durability
(200 percent).
As with the predecessor model,
unveiled in 2017, the upgraded
NCC199CDV offers a maximum
input of 199,900 Btu per hour; a
capacity range of 0.29 to 11.1
gallons per minute; water temperatures from 100°F to 185°F;
and a thermal efficiency rating
of 98 percent /0.97 UEF. The
new NCC199CDV can also
direct-vent, using either 2-inch
or 3-inch PVC, CPVC, or rigid
polypropylene materials. However, vent lengths have been extended: 65 feet for 2-inch
pipe, up from the previous 60 feet; and 150 feet (instead
of 100 feet) for three-inch pipe.
The units can also be installed
outdoors or on a rooftop with an
optional vent cap. Up to 24
NCC199CDV units can be linked
together in a single system, using
a Multi-Unit System Controller, to
meet the hot-water needs of highvolume commercial and industrial applications:
restaurants, schools, assisted living facilities,
breweries, hospitality, correctional facilities,
factories, etc. Inputs can range from 18,000 to
4.8 million BTU/h (for a 24-unit multi-system),
yielding up to a 266:1 turndown ratio.
input #16 at www.csemag.com/information
Baptist Health and Specified Technologies Inc (STI)
established an Above Ceiling Access and Barrier Management
Policy and Procedure that standardized firestopping
to ensure compliance and occupant safety.
Baptist Health is the largest health system in the state of Arkansas,
with 11 community hospitals and 3,000 beds, as well as clinics and
multiple ancillary facilities at campuses throughout the state.
Baptist Health recognized the need to establish a program to
improve its life safety systems in hiring engineer Joshua Brackett,
PE, SASHE, CHFM, as Special Projects Manager in 2017.
Contractors performing above ceiling projects did a great job with
the plumbing and/or electrical work, but they weren’t always firestopping when the jobs were completed. “Our goal was to establish
procedures and permit process not only to ensure compliance, but
occupant safety – we have to protect patients,” Brackett said. “We
needed to create an above the ceiling permit program that had some
teeth in it for all of our primary facilities.”
The solution: a rigid Above Ceiling Access and Barrier
Management Policy and Procedure was established that changed
the way contractors performed services at specified BH facilities.
It formalizes how work is expected to be performed.
“The fact that STI Firestop provides training was another critical
function in our decision. Most of the certified contractors, staff
leaders, and supervisors have been trained by STI. It’s important
that everybody understands firestopping and the criticality
associated with passive fire protection, especially in defend in
place occupancies.”
BH also established an in-house firestopping products stocking
program, standardizing on STI Firestop products including EZ-Path.
Anything that involves new cabling has to go through an EZ-Path.
“I worked with EZ-Path as a specifying engineer and loved the
application,” Brackett said.
The Above Ceiling Access and Barrier Management Policy and
Procedure program accomplished the unthinkable: changing the
“we’ve always done it that way” mentality. “There’s a reason we do
this – it’s because of smoke and fire,” Brackett said. “It’s on all of
us to protect patients. Bottom line is, we’re all legally liable for
patients’ lives.”
input #17 at www.csemag.com/information
Ultrasonic Flow Sensor with Glycol Measurement
Trusted flow measurement is essential in maximizing HVAC system efficiency
and ensuring occupant comfort. Belimo flow sensors utilize ultrasonic
technology with glycol compensation to provide accurate and repeatable
flow measurements of water and water/glycol mixtures without drift in any
HVAC application.
The flow sensors have a patented automatic glycol compensation algorithm
that selects the correct fluid properties for the flow and energy calculation
eliminating manual input of glycol percentage for sensor setup. The algorithm
can be applied to a range of heat transfer fluids, ensuring accurate and repeatable measurements. The automatic
glycol concentration minimizes drift and provides trusted flow measurement by continuously compensating
glycol concentration in a hydronic system. The Belimo inline flow sensors are an advancement in thermal energy
with ultrasonic transit-time technology that automatically measures and compensates glycol concentration.
‘Fit and forget’ sensors to compensate variable and changing viscosities. The sensors have a rugged design with
no moving parts, require no calibration, and provide accurate, repeatable measurements improving the control
and efficiency of HVAC systems. All flow sensors are wet calibrated to simulate
field operation and available with NIST traceable calibration certification.
The FM series flow sensors offering are available ½” to 6”.
Learn more at www.belimo.us
cse202006_innovHalf_belimo.indd 1
5/7/2020 11:51:16 AM
input #18 at www.csemag.com/information
Plug into Safety and Innovation with MELTRIC!
MELTRIC manufactures safe, reliable UL/CSA Switch-Rated plugs and receptacles with
push-button circuit disconnection. These all-in-one devices combine the safety and
functionality of a disconnect switch with the convenience of a plug and receptacle.
As a safety leader in the electrical manufacturing industry for more than 35 years,
MELTRIC designs and builds quality electrical connectors that emphasize electrical
and user safety, and improve maintenance efficiency.
Safe and Innovative Products
MELTRIC Switch-Rated products lead the U.S. electrical marketplace with
innovative designs and safety features, including:
• UL/CSA ratings for motor and branch
circuit disconnect switching
• Ability to safely make and break
connections under full load
• An enclosed arc chamber that
eliminates arcing at disconnection
• Type 4X/IP69/IP69K ingress protection
• Corrosion-resistant spring-loaded
silver- nickel butt-style contacts that
deliver superior electrical conductivity
for thousands of operations
• Built-in provisions for lockout/tagout
• Dead-front safety shutter that prevents
access to live parts
• Plug and receptacle separation that
verifies deenergization without voltage
testing or additional PPE required
• 5-Year warranty on electrical contacts
Visit Meltric.com for electrical safety information, to learn more
about our innovative Switch-Rated plugs and receptacles, and to
check out the MELTRIC free sample offer.
mail@meltric.com | 414-433-2700 | Meltric.com
input #19 at www.csemag.com/information
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5/5/2020 2:19:41 PM
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June 2020
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June 2020
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Uncomplicate Your Day
Control Your HVAC System With Yaskawa Drives
Controlling comfort throughout a facility presents unique challenges.
Make your complicated day simple by using Yaskawa variable frequency
drives for reliable, consistent performance.
Whether you are looking at a new project or a retrofit, consider Yaskawa
drives. Our Z1000 and Z1000U Matrix drives are designed specifically for
your HVAC applications and deliver simplicity, efficiency, and low harmonics
at all loads to meet your specific needs.
Yaskawa. We make the complicated simple.
Yaskawa America, Inc.
Drives & Motion Division
input #21 at www.csemag.com/information
Onboard genset paralleling saves space and money.
Paralleling Cat® generator sets ensures efficient load sharing and
response, using onboard controls to:
• Eliminate the need for traditional switchgear
• Create a smaller footprint
More about paralleling gensets at: www.cat.com/paralleling
© 2020 Caterpillar. All Rights Reserved. CAT, CATERPILLAR, LET’S DO THE WORK, their respective logos, “Caterpillar Corporate Yellow”, the “Power Edge” and
Cat “Modern Hex” trade dress as well as corporate and product identity used herein, are trademarks of Caterpillar and may not be used without permission.
input #22 at www.csemag.com/information