Policy and Procedure for Electrical Safety and Control of Arc Flash

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Policy and Procedure for
Electrical Safety and Control
of Arc Flash Hazards
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Objective: To protect all persons who are required to work on the university’s electrical
distribution systems from injury or death due to electrical hazards including Arc Flash.
Authority: Vice President for Administration
Introduction:
Electricity can be a potentially serious safety hazard in the workplace
which could cause injury, death and property damage. It is the policy of Concordia University
Chicago to protect all persons from these electrical hazards through compliance with
university safety practices and work procedures as described in this policy.
The primary rule of this policy is to avoid working on or near energized electrical circuits or
equipment unless it is absolutely necessary and if one of these conditions applies:
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De-energizing the circuit would cause additional or increased hazards.
De-energizing the circuit is not possible due to the equipment’s design or
operating limitations.
The circuit operates at 50 volts or less and there is no potential for an electrical
arc.
Explanation:
Control of electrical hazards including Arc Flash (OSHA 29 CFR 1910.301
- .399) and as described in NFPA 70E shall be used as guides in this policy for electrical safety
in the workplace.
Responsibilities:
The following establishes specific responsibilities for the policy.
1. The Safety Officer shall:
* Implement and enforce the policy.
* Provide appropriate training
* Maintain documentation related to this policy
* Review contractor policies as related to electrical safety
2. Supervisors shall:
* Implement this policy within their scope of responsibility
* Insure that their employees are in compliance with this policy including the
use of Lockout/tagout (LOTO) and the wearing of required Personal
Protective Equipment (PPE).
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3. Employees shall:
* Observe all work practices as described in this policy
* Attend required training relative to this policy
* Wear required clothing and PPE as related to the level of electrical hazard(s)
that would be present for the work being done
* Report any electrical safety concerns to their Supervisor or the Campus
Safety Officer
Definitions:
Arc Flash Hazard – A dangerous condition associated with the possible release of
energy caused by an electrical arc.
Arc Flash Hazard Analysis – A study to investigate a worker’s potential exposure to
arc-flash energy, conducted for the purpose of injury prevention and the
determination of safe work practices along with appropriate levels of PPE.
Arc Flash Suit – A complete flame resistant (FR) clothing and equipment system that
covers the entire body, except the hands and feet. (Such a suit typically includes
pants, jacket, and a “bee-keeper” style hood fitted with a face shield).
Arc Rating – The value attributed to materials that describe their performance to
exposure to an electrical discharge. The arc rating is expressed in cal/cm² and is
derived from the determined value of the arc thermal performance value (ATPV).
Balaclava (Sock Hood) – An arc-rated FR hood that protects the neck and head except
for facial area of the eyes and nose.
Bare-hand Work – A technique of performing work on energized electrical conductors
or circuit parts, after the employee has been raised to the potential of the conductor
or circuit part.
Barricade – A physical obstruction such as tapes, cones, or A-frame wood or metal
structures intended to provide a warning about and to limit access to a hazardous
area.
Barrier – A physical obstruction that is intended to prevent contact with equipment or
energized electrical conductors and circuit parts or to prevent unauthorized access to
a work area.
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Boundary, Arc Flash Protection – When an arc flash hazard exists, an approach limit at
a distance from a prospective arc source within which a person could receive a second
degree burn if an electrical arc flash were to occur.
Boundary, Limited Approach – An approach limit at a distance from an exposed
energized electrical conductor or circuit part within which a shock hazard exists.
Boundary, Prohibited Approach – An approach limit at a distance from an exposed
energized electrical conductor or circuit part within which work is considered the
same as making contact with the electrical conductor or circuit part.
Boundary, Restricted Approach – An approach limit at a distance from an exposed
energized electrical conductor or circuit part within which there is an increased risk of
shock, due to electrical arc over combined with inadvertent movement, for personnel
working in close proximity to the energized electrical conductor or circuit part.
Branch-Circuit Overcurrent Device – A device capable of providing protection for
service, feeder, and branch circuits and equipment over a full range of overcurrents
between its rated current and its interrupting rating. Branch-circuit overcurrent
protective devices are provided with interrupting ratings appropriate for the intended
use but not less than 5,000 amperes.
Circuit Breaker – A device designed to open and close a circuit by nonautomatic means
and to open the circuit automatically on a predetermined overcurrent without
damage to itself when properly applied within its rating.
Conductive – Suitable for carrying electrical current.
Current-Limiting Overcurrent Protective Device – A Device that, when interrupting
currents in its current limiting range, reduces the current flowing in the faulted circuit
to a magnitude substantially less than that obtainable in the same circuit if the device
were replaced with a solid conductor having comparable impedance.
Deenergized - Free from all electrical connection to a source of potential and from
electrical charge; not having a potential difference from that of the earth.
Electrical Hazard – A dangerous condition such that contact or equipment failure can
result in electrical shock, arc flash burn, thermal burn, or blast.
Electrical Safety – Recognizing hazards associated with the use of electrical energy and
taking precautions so that those hazards do not cause injury or death.
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Electrically Safe Work Condition – A state in which an electrical conductor or circuit
part has been disconnected from energized parts, locked/tagged in accordance with
established standards and the University’s policy on LOTO, tested to ensure the
absence of voltage, and grounded if determined necessary.
Enclosure – The case or housing surrounding an installation to prevent personnel from
accidently contacting energized electrical conductors or circuit parts or to protect the
equipment from physical damage.
Energized – Electrically connected to, or is, a source of voltage.
Exposed (as applied to energized electrical conductors or circuit parts) – Capable of
being inadvertently touched or approached nearer than a safe distance by a person. It
is applied to electrical conductors or circuit parts that are not suitably guarded,
isolated, or insulated.
FR Apparel – Flame-resistant apparel; describes a broad category of clothing designed
to protect persons from electrical arc events during energized tasks.
Flame-resistant (FR) – The property of a material whereby combustion is prevented,
terminated, or inhibited following the application of a flaming or non-flaming source
of ignition, with or without subsequent removal of the ignition source. Flame
resistance can be an inherent property of a material, or it can be a specific treatment
applied to the material.
Incident Energy – The amount of energy impressed on a surface, a certain distance
from the source, generated during an electrical arc event. One of the units to measure
incident energy is calories per centimeter squared (cal/cm²).
Insulated – Separated from other conducting surfaces by a dielectric (including air
space) offering a high resistance to the passage of current.
Live Parts – Energized conductive components.
Lockout/Tagout (LOTO) – Control of unexpected start-up of machines and equipment,
or the release of stored electrical energy, in order to prevent injuries or fatalities
through the use of a locking device or placement of a warning tag(s) while in a safe
work condition.
PPE – Acronym for “Personal Protective Equipment”.
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Qualified Person – One who has skills and knowledge related to the construction and
operation of the electrical equipment and installation and has received safety training
to recognize and avoid the hazards involved.
Service Point – The point of connection between the facilities of the serving utility and
the premises wiring.
Shock Hazard – A dangerous condition associated with the possible release of energy
caused by contact or approach to energized electrical conductors or circuit parts.
Switch, Isolating – A switch intended for isolating an electric circuit from the source of
power. It has no interrupting rating, and it is operated only after the circuit has been
opened by some other means.
Touch Potential – A ground potential gradient difference that can cause current flow
from hand to hand, hand to foot, or another path, other than foot to foot through the
body.
Unqualified Person – A person who is not qualified to perform direct work on an
energized electrical conductor or circuit part.
Working Near (live parts) – Any activity within a Limited Approach Boundary.
Working On (energized electrical conductors or circuit parts) – Coming into contact
with energized electrical conductors or circuit parts with the hands, feet, or other
body parts, with tools, probes, or with test equipment, regardless of the personal
protective equipment a person is wearing.
Procedure:
Controlling Electrical Hazards
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All energized electrical work over 50 volts requires an “Energized Electrical Work
Permit”.
The “Energized Electrical Work Permit” can be obtained from the Campus Safety
Officer or the Director of Physical Plant.
The “Energized Electrical Work Permit” must be filled out by the Qualified Person
that will be doing the work and approved by the Director of Physical Plant or
Campus Safety Officer prior to the commencement of work except in the case of
an emergency. The permit must be posted in the area that the work is being
performed. Upon completion of the energized electrical work the permit will be
given to the Campus Safety Officer who will retain it on file for one year.
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Safe work practices and appropriate PPE are required when doing energized
electrical work related to testing, troubleshooting, and/or electrical
measurements.
Employees doing energized electrical work are required to wear fire-resistant (FR)
work clothes including under garments and use appropriate PPE for the rated level
of electrical hazard.
Employees shall not reach blindly into areas that might contain live parts.
Employees shall not enter spaces containing live parts unless the illumination in
that space is sufficient to allow the work to be performed safely.
Employees shall not wear conductive articles of jewelry or clothing (such as, but
not limited to watches, rings, bracelets, necklaces, exposed keys, clothes with
conductive threads, metal headgear and metal eyeglass frames) when working on
or near energized and exposed electrical conductors or circuit parts.
To prevent accidental contact with live parts, conductive material, tools and
equipment (such as, but not limited to metal pipes, tubes, hoses, tapes, pulling
lines, tools, chains, ladders and scaffolding) shall not be used while working on
energized and exposed electrical conductors or circuit parts.
Employees working on energized and exposed electrical conductors or circuit parts
shall use protective shields, barriers, or barricades and observe all safety
boundaries that have been established.
Personal Protective Equipment (PPE)
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Electrical protective equipment (Arc Flash Suit), which is designed and constructed
for the specific body part for the work being performed, shall be provided to
employees who are required to work on energized electrical conductors or circuit
parts.
CUC will provide electrical protective equipment to its employees that are
required to work in electrical hazardous areas, at no cost. Such equipment shall
include but not be limited to Arc Flash rated apparel, eye protection, head
protection, hand protection, rated footwear, and face shields. CUC is not
responsible for providing FR rated under garments.
All electrical protective equipment shall be maintained in a suitable manor so as to
be ready for safe use at any time by the employee it’s assigned to.
Face shields that are not arc rated shall not be used for electrical work. Safety
glasses or goggles must be worn in conjunction with face shields.
When using a tinted face shield additional lighting may be required.
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Flash Protection Boundary
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All employees are required to wear assigned appropriate PPE when working within
the Flash Protection Boundary. Appropriate PPE can be selected based on the
calculated exposure level.
The Flash Protection Boundary for systems of 50 to 600 volts shall be a minimum
of 4 feet or as established through engineering analysis. For systems over 600
volts the Flash Protection Boundary shall be determined through engineering
analysis.
Specific electrical PPE to be worn in the Flash Protection Boundary can be
determined by using either of the following two methods:
ᵒ Complete a flash hazard analysis to determine the incident exposure energy of
each employee. Appropriate PPE can then be selected based on the calculated
exposure level.
ᵒ Or by referring to NFPA 70E Table 130.7(C) (9) (a), “Hazard/Risk Category
Classifications”. This table will also indicate whether voltage-rated gloves
and/or tools are required. Once the hazard level has been determined, the
required PPE can be selected from NFPA 70E Table 130.7 (C) (10), “Protective
Clothing and PPE Matrix”.
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Flame-Resistant Apparel
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A visual inspection of FR apparel shall be performed before each use. Apparel that
is damaged or contaminated shall not be used. Items contaminated with oil,
grease, flammable or combustible liquids shall not be used.
Care and maintenance of FR apparel should follow the manufactures
recommendations and instructions.
FR apparel must cover any potentially exposed areas as completely as possible.
Shirtsleeves must be fastened and shirts/jackets must be closed at the neck.
Non-melting garments (such as cotton and wool) may be used as under layers
beneath FR apparel. Meltable fibers such as acetate, nylon, polyester
polypropylene, and spandex shall not be worn as under garments next to the skin.
Garments worn over FR apparel (i.e. jackets or rainwear) must also be of FR rated
material.
Flash suits must permit ease of removal by the employee.
Rubber Insulating Equipment
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Electrical protective rubber insulating equipment such as gloves, sleeves, blankets
and matting that are rated may be used.
This insulating equipment shall be inspected prior to use and after use if damage
may have occurred during use.
Rubber insulating gloves must be air tested before each use.
Insulating equipment that is found to be defective must be removed from service
and repaired or replaced.
Rubber insulating equipment must be stored in an area protected from light,
temperature extremes, excessive humidity, ozone and other substances and
conditions that may cause damage.
Insulating Tools and Materials
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Only insulated tools and equipment shall be used within the Limited Approach
Boundary of energized and exposed electrical parts.
The rating of the insulated tools being used must be correct for the voltage.
The integrity of the insulation on the tools shall be protected from damage and
degradation.
Fuses and/or fuse handling equipment shall be used to remove or install fuses if
the fuse terminals are energized.
Ropes and hand lines used for electrical work near energized and exposed
conductors or circuit parts must be nonconductive.
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Ladders used during electrical work must be nonconductive.
Alerting Techniques
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Barricades shall be used in conjunction with safety signage to prevent or limit
access to work areas where energized and/or exposed electrical conductors or
circuit parts are. Barricades shall be placed no closer than the Limited Approach
Boundary.
If the area where energized and/or exposed electrical conductors or circuit parts
cannot be secured, then a person must be stationed to prevent anyone from
entering the Flash Protected Boundary area.
Electrical Contractors and Contracted Employees
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The safety programs of contractors used by CUC must meet or exceed all
applicable guidelines of this policy.
All contractors shall be required to comply with applicable regulations and
standards issued by the AHJ, OSHA, NFPA, EPA, IEPA, etc.
Contractors are required to submit a copy of their Electrical Safety Program to the
Campus Safety Officer for review.
Electrical Arc Flash Protection
Standard Operating Procedure
It is the goal of Concordia University Chicago to control the arc flash hazard which is present
during the maintenance of electrical building components throughout the campus. Standard
operating procedures will help control and/or eliminate arc flash events in order to protect
employees from electrical hazards.
To reduce the potential for arc flash occurrences, the following standard operating
procedures will apply:
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De-energize all circuits prior to the start of any electrical maintenance work.
Ensure that all possible sources of electrical supply are found and disconnected by
means of an isolating switch.
Perform LOTO in accordance with the university’s policy for LOTO.
Test for any voltage between conductors and between each conductor and ground
to verify that all voltage has been removed. Properly rated FR apparel and PPE, for
the level of potential electrical hazard, shall be worn.
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If stored energy or induced voltage is determined to exist or where de-energized
conductors could contact live parts, the application of grounding devices must be
used.
If the circuits or equipment cannot be de-energized for any reason and the work must be
performed while energized the following procedures will apply:
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Establish Flash Protection Boundaries so as to keep those not involved with the
electrical work at a safe distance away.
Use insulated tools that are rated for the level of electrical hazard present.
Use insulated and rated rubber floor matting.
Properly rated arc flash clothing and PPE, for the level of potential electrical arc
flash, shall be worn. PPE should include safety glasses or goggles, voltage rated
gloves, rated hard-soled leather work shoes or dielectric overshoes.
Training
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Any employee, who through their normal scope of work is exposed to electrical
hazards, must be trained in electrical safety, including LOTO.
The level of electrical safety training is dependent on whether the employee is
classified as a “qualified person” or an “unqualified person”.
A “qualified person” shall have training for and knowledge of the following topics:
ᵒ Operation and conditions of electrical conducting equipment.
ᵒ Skills necessary to identify exposed energized parts from other parts in the
electrical equipment.
ᵒ Use of electrical measurement equipment to determine the presence of
voltage at the conductor or electrical part.
ᵒ Ability to determine the approach distances and the corresponding voltages to
which the employee will be exposed.
ᵒ The process necessary to determine the degree and extent of electrical
hazards present, along with the required PPE and job planning necessary to
safely perform the work.
A person can be considered qualified with respect to specific equipment but
unqualified on other equipment.
An “unqualified person” should be trained to recognize any electrical hazards and
work practices necessary for their safety.
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Training shall be provided to employees prior to being assigned work that involves
work near or on electrical systems.
The Campus Safety Officer shall maintain a record of all electrical training attended
by CUC employees, both in-house and through outside vendors. A master list will
be kept for all employees that are classified as a “qualified person”.
Adopted: May 10, 2012
Latest review: January 19, 2016
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