Designing to prevent disasters

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Designing to Prevent Disasters:
Mechanical System Failures
and Physical Plant Design
Bill Zavatkay PE, LEED AP BD+C – HDR
Mechanical Engineering Section Manager
Introduction
Disasters
A
Regulatory Requirements
Physical Plant
By definition, a disaster is, "an occurrence causing
widespread destruction and distress, a grave
misfortune, a total failure..." A disaster is often
further defined as being either a man-made or
natural event that results in death, injury, and
property damage which cannot be managed
through normal, routine channels.
(Source: Google…Author not indicated).
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Introduction
Disasters
B
Regulatory Requirements
Physical Plant
What we typically think of as a Disaster?
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Widespread flooding from levee breaches and
storm surge
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Widespread flooding from levee breaches and
storm surge
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Wind and flood damage
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Wind damage to buildings
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Tree damage to buildings
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Impassable roads
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Natural disasters occur and make big
headlines, but more likely events
include:
• Facility Failures
• Operational Issues
• Power Outages
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Fires
Failed Equipment
Broken Pipes
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Introduction
Disasters
C
Regulatory Requirements
Physical Plant
R E G U L ATO RY R E Q U I R E M E N T S
Green / Sustainable / LEED / Energy Star /
ASHRAE 90.1 = “SAVE THE PLANET”
Building codes / GUIDE / BMBL / WHO / NIH DRM
/ AALAC / USDA = “Safety”
•
•
•
•
Safety for building occupants as well as “the public”
Minimum exhaust stack velocities (vs energy savings)
Redundant equipment (increased electrical load)
Spare capacity (effects on operation energy use)
Combined equals your Project
2014 ACLAM FORUM: Coeur d’Alene, Idaho
T H E G U I D E – B A S I C H VA C R E Q U I R E M E N T S
» Performance Based Approach
• Temperature and humidity control to minimize variations.
• Pressurization Control – Directional Airflow
• HVAC system to be designed for reliability, ease of
maintenance and energy conservation.
• Temperature: 68-79 deg F, maintain +\- 2 degrees F (varies
based on species)
• Maintain Humidity 30-70% year round.
• Redundancy
• Temperature control for each holding space.
• Emergency power for critical services (HVAC, freezers,
ventilated racks, isolators)
2014 ACLAM FORUM: Coeur d’Alene, Idaho
N I H D R M - B A S I C H VA C R E Q U I R E M E N T S
» Prescriptive Based Approach
• Animal Facilities shall meet the requirements of “The Guide”
• Laboratory Spaces shall meet the requirements of the
BMBL.
• Design conditions: ASHRAE 0.4% summer, 99.6% winter
• Equipment sized for 20% future expansion.
• 15 ACH Small Animal Static Rack/Large Animal
• 10 ACH Small Animal Ventilated Rack
• Exhaust fans on emergency power.
• Dedicated Air Systems
» Non-Research Function
» Animal Areas
» Lab General Research.
• N+1 Redundancy Required.
• Emergency Power Required; AHU’s, EF, chillers, boilers,
pumps, etc.
2014 ACLAM FORUM: Coeur d’Alene, Idaho
T H E G U I D E – PA G E 3 5
Animal facilities may be subject to unexpected conditions
that result in the catastrophic failure of critical systems or
significant personnel absenteeism, or other unexpected
events that severely compromise ongoing animal care and
well-being (ILAR 2010). Facilities
have a disaster plan.
must therefore
The plan should define the
actions necessary to prevent animal pain, distress,
and deaths due to loss of systems such as those
that control ventilation, cooling, heating, or
provision of potable water. If possible the plan should
describe how the facility will preserve animals that are
necessary for critical research activities or the irreplaceable.
Knowledge of the geographic locale may provide guidance
as to the probability of a particular type of disaster.
2014 ACLAM FORUM: Coeur d’Alene, Idaho
NIH GUIDELINES
» “Spare”
•
•
•
•
•
Capacity Issues
Different than redundancy or reliability
Owner driven (program revisions)
NIH DRM requirements for 20% spare capacity
Process loads (large % of total load)
Major equipment turndown Issues
» Chillers
» Boilers
n+1 + 20%
» AHU Components
•
•
•
•
•
Coils
Filters
Fans
Humidifiers
Airflow Stations
» Exhaust fans
=
Potential
Loss of
Efficiency
Until Used
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Introduction
Disaster Preparedness
D
Regulatory Requirements
Physical Plant
“ S I N G L E P O I N T O F FA I L U R E ”
• Every system will fail at the least
opportunistic time.
• Design, plan, educate and train to
eliminate or provide redundancy for
every critical system.
2014 ACLAM FORUM: Coeur d’Alene, Idaho
“ S I N G L E P O I N T O F FA I L U R E ”
Identify all Critical systems:
MEP Systems:
•
•
•
•
•
•
•
Air Handling Units
Exhaust Fans
Cooling
Heating
Controls
Potable Water
Power
2014 ACLAM FORUM: Coeur d’Alene, Idaho
“ S I N G L E P O I N T O F FA I L U R E ”
MEP Critical systems:
•
•
•
Need Redundancy
Need Spare Parts
Need Maintenance Staff to Install
Spare Parts
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
Reliability is a measure of probability that the
environmental systems will be operational at the time
that it is required.
Redundancy is a subset of reliability and can be
achieved by the engineering systems, or a
combination of engineering systems and protocols
2 at 50%
3 at 33%
4 at 25%
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
No redundancy Scenario
 One AHU and one EF serves each zone
Lab
Zone
Lab
Zone
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
Partial Redundancy Scenario
 Requires ductwork and control dampers to allow
interconnection of air systems
 Requires extensive ceiling space
 Reduces quantity of equipment to provide
redundancy
Lab
Zone
Lab
Zone
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
Fully Redundant Scenario – 2N or 2@50%
 Greater equipment requirements
 Automatic Operation
 Less dependency upon other systems
Lab
Zone
Lab
Zone
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
Reliability & Redundancy
• independent systems
• N+1 (100%) back-up capability
desirable
• Less than N+1 with load shedding
• consider utilizing systems adjacent to
vivarium spaces as an alternate means
to provide redundancy
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
 AHU fan redundancy
options
 Fan Wall
 Dual Fans
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
Failure Protection - Automation
• normal operation
• exhaust failure – supply reacts
• supply failure – exhaust reacts
• BAS controls & interlocks
• maintain directional airflow (positive or
negative pressurization)
• consider ‘load shedding’ strategies
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
Central Utilities (Campus ScenarioIssues)
• Large Chiller Plants typically not
on emergency power backup
• Large Boiler Plants typically not
on emergency power backup
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
Central Utilities (Campus ScenarioResolutions)
• Consider providing small backup
air cooled chiller and pumps for
critical cooling.
• Consider providing small backup
boiler and pumps for critical
heating
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
Potable Water
• Consider providing potable water
backup storage tank if water outage
typical.
• Provide maintenance staff on hand to
repair pipe leaks.
• Ensure shut-off valves are in place in
case of emergency.
• Periodically exercise valves to ensure
they will be operational when required.
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT - POWER
Normal Power
• Redundant Feeders to a double ended
substation
•Redundancy and independent
electric services
•Should come from two separate
utility generating stations (Or from
two separate substations on a
campus configuration)
•Feeders should be in separate duct
banks and routing.
• Provides redundancy in feeders and in
services to building.
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT - POWER
EM Power
• Generators
• Serve critical equipment
•Supply air handlers
•Exhaust fans
•Caging systems (IVCs)
•Heating & Cooling systems
•Distribution pumps
•BAS system controllers
UPS
• BAS control panels to keep from
resetting controls to minimize
downtime under any failure
scenario
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT…
Locate vivarium above flood elevation
levels – New facilities
» Flood gates or retaining walls around
existing facilities
 Locate physical plant above flood
elevation levels
 Locate electrical switchgear above floor
elevation levels
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT…
 Provide adequate level of redundancy
 Provide automated control
 Provide Emergency Power Backup
 Locate generators above flood elevation
level
 Provide “enough” fuel capacity for
sustained duration for outage based on
risk assessment
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT…
 Fail closed reheat coil valves
 Fail open AHU preheat valve
 Fail open AHU cooling coil valves
 Interlock AHU’s with EF’s
 Interlock supply and exhaust air
valves
 Security systems to prevent
unwanted entry
 Seismic reinforcement
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT…
 Snowfall issues and AHU
shutdowns
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT…
 Provide snow melt device such
as MISTOP Snostop
 Provide bypass damper across
filters that opens on high filter
delta P
 Remove AHU pre-filters before
snow occurrences
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT –
MAINTENANCE
• Access Outside Vivarium
• Locate Equipment where it
is accessible
• Routine Inspection
• Preventative Maintenance
• Minimize Impact on Science
• High Tech vs. Low Tech
2014 ACLAM FORUM: Coeur d’Alene, Idaho
T H E B I O D E S I G N I N S T I T U T E AT A S U
2014 ACLAM FORUM: Coeur d’Alene, Idaho
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
2014 ACLAM FORUM: Coeur d’Alene, Idaho
PHYSICAL PLANT
2014 ACLAM FORUM: Coeur d’Alene, Idaho
Questions?
2014 ACLAM FORUM: Coeur d’Alene, Idaho
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