Attachment G

V. 1.1 12/22/2008

Flame Resistant Clothing Requirements

Attachment G - Flame Resistant Clothing Recommendations
Including NFPA 70E-2007 Table 130.7(C)(9)(a) Hazard/Risk Category Classifications

(Extracted from NFPA 70E and the Facilities Management Arc Flash Protection Program)

From NFPA 70E:

Personal Protective Equipment

General. When an employee is working within the Flash Protection Boundary he/she shall wear protective clothing and other personal protective equipment in accordance with 130.3.
Movement and Visibility. When flame-resistant (FR) clothing is worn to protect an employee, it shall cover all ignitible clothing and shall allow for movement and visibility.
Head, Face, Neck, and Chin Protection. Employees shall wear nonconductive head protection wherever there is a danger of head injury from electric shock or burns due to contact with live parts or from flying objects resulting from electrical explosion. Employees shall wear nonconductive protective equipment for the face, neck, and chin whenever there is a danger of injury from exposure to electric arcs or flashes or from flying objects resulting from electrical explosion.
FPN: See 130.7(C)(13)(b) for arc flash protective requirements.
Eye Protection. Employees shall wear protective equipment for the eyes whenever there is danger of injury from electric arcs, flashes, or from flying objects resulting from electrical explosion.
Body Protection. Employees shall wear FR clothing wherever there is possible exposure to an electric arc flash above the threshold incident-energy level for a second-degree burn, 5 J/cm2 (1.2 cal/cm2).

Exception: For incident-energy exposures 8.36 J/cm2 (2 cal/cm2) and below, employees may wear non-melting clothing described in Hazard/Risk Category 0 in Table 130.7(C)(11).
Hand and Arm Protection. Employees shall wear rubber insulating gloves where there is danger of hand and arm injury from electric shock due to contact with live parts. Hand and arm protection shall be worn where there is possible exposure to arc flash burn. The apparel described in 130.7(C)(13)(c) shall be required for protection of hands from burns. Arm protection shall be accomplished by apparel described in 130.7(C)(5).
Foot and Leg Protection. Where insulated footwear is used as protection against step and touch potential, dielectric overshoes shall be required. Insulated soles shall not be used as primary electrical protection.
Standards for Personal Protective Equipment. Personal protective equipment shall conform to the standards given in Table 130.7(C)(8).
Selection of Personal Protective Equipment.

(a) When Required for Various Tasks. When selected in lieu of the flash hazard analysis of 130.3(A), Table 130.7(C)(9)(a) shall be used to determine the hazard/risk category for a task. The assumed short-circuit current capacities and fault clearing times for various tasks are listed in the text and notes to Table 130.7(C)(9)(a). For tasks not listed, or for power systems with greater than the assumed short-circuit current capacity or with longer than the assumed fault clearing times, a flash hazard analysis shall be required in accordance with 130.3.

FPN No. 1: Both larger and smaller available short-circuit currents could result in higher available arc-flash energies. If the available short-circuit current increases without a decrease in the opening time of the overcurrent protective device, the arc-flash energy will increase. If the available short-circuit current decreases, resulting in a longer opening time for the overcurrent protective device, arc-flash energies could also increase.

FPN No. 2: Energized parts that operate at less than 50 volts are not required to be de-energized to satisfy an “electrically safe work condition.” Consideration should be given to the capacity of the source, any overcurrent protection between the energy source and the worker, and whether the work task related to the source operating at less than 50 volts increases exposure to electrical burns or to explosion from an electric arc.

Arc Flash Hazard Analysis (From Facilities Management Arc Flash Protection Program)

An arc flash hazard analysis shall be done before a person approaches any exposed electrical conductor or circuit part that has not been placed in an electrically safe work condition.

The arc flash protection boundary shall be utilized to initiate the need for personal protective equipment. Refer to chapter 1, section 130.3 and Annex D of NFPA 70E2004 for formulas and other information needed to establish the arc flash protection boundary. Chapter 1, section 130.7 and Annex H in NFPA 70E also contain information and recommendations that address personal protective equipment required for personnel to cross inside the arc flash protection boundary.

Flame Resistant (FR) Clothing and Personal Protective Equipment (PPE) shall be used by the employee based upon the incident energy exposure associated with the specific task. As an alternative, the PPE requirements outlined chapter 1, section 130.7 of NFPA 70E may be used.

For systems which are 600 volts and below, the arc flash protection boundary shall be

4.0 feet, based on the product of clearing times of 6 cycles (0.1 seconds) and the available bolted fault current of 50 kA or any combination not to exceed 300kA cycles (5000 ampere seconds). For clearing times and bolted fault currents other than 300 kA cycles, or under engineering supervision, the arc flash protection boundary may alternatively be calculated using information and formulas outlined in NFPA 70E-2004 section 130.3(A).

At voltage levels above 600 volts, the arc flash protection boundary is the distance at which the incident energy level equals 1.2 cal/cm². For situations where fault clearing time is 0.1 second (or faster), the arc flash protection boundary is the distance at which the incident energy level equals 1.5 cal/cm².

Existing knowledge about arc flash exposure at voltage levels above 600 volts is limited. Other methods of calculating such exposure exist and may be used. Commercial and shareware programs are available for calculating these values. It is important to investigate the limitations of any programs to be used. It should be noted that all present methods of calculating incident energy at higher voltage levels have limitations.

Equations for calculating the incident energy produced by a three phase arc on systems rated 600 volts and below for an “Arc in Open Air” (Ema ) and an “Arc in a Cubic Box” (Emb - arc flashes emanating from within switchgear, motor control centers, or other electrical equipment enclosures) may be calculated by using the formulas derived in the IEEE paper by R.L. Doughty, T.E. Neal, and H. L. Floyd, “Predicting Incident Energy to Better Manage the Electric Arc Hazard on 600 Volt Power Distribution Systems,” IEEE Sept 30, 1998.

NOTE: See Annex D for Sample Calculation of the Arc Flash Protection Boundary Dc, Arc in Open Air Ema, and Arc in Cubic Box Emb (formulas hold for current range from 16 kA to 50 kA only).

Table 130.7(C)(9)(a) Hazard/Risk Category Classifications From NFPA 70E-2007

Panelboards Rated 240V and Below- Notes 1 and 3
Task (Assumes Equipment Is Energized, and Work Is Done Within the Flash Protection Boundary)	Hazard/ Risk Category	V-rated Gloves	V-rated Tools
Circuit breaker (CB) or fused switch operation with covers on	0	N	N
CB or fused switch operation with covers off	0	N	N
Work on energized parts, including voltage testing	1	Y	Y
Remove/install CBs or fused switches	1	Y	Y
Removal of bolted covers (to expose bare, energized parts)	1	N	N
Opening hinged covers (to expose bare, energized parts)	0	N	N

Panelboards Rated > 240V and Up To 600 V (with molded case or insulated case circuit breakers) - Notes 1 and 3
Task (Assumes Equipment Is Energized, and Work Is Done Within the Flash Protection Boundary)	Hazard/ Risk Category	V-rated Gloves	V-rated Tools
CB or fused switch operation with covers on	0	N	N
CB or fused switch operation with covers off	1	N	N
Work on energized parts, including voltage testing	2	Y	Y

600 V Class Motor Control Centers (MCCs) - Notes 2 (except as indicated) and 3
Task (Assumes Equipment Is Energized, and Work Is Done Within the Flash Protection Boundary)	Hazard/ Risk Category	V-rated Gloves	V-rated Tools
CB or fused switch or starter operation with enclosure doors closed	0	N	N
Reading a panel meter while operating a meter switch	0	N	N
CB or fused switch or starter operation with enclosure doors open	1	N	N
Work on energized parts, including voltage testing	2	Y	Y
Work on control circuits with energized parts 120 V or below, exposed	0	Y	Y
Work on control circuits with energized parts >120 V, exposed	2	y	y
Insertion or removal of individual starter “buckets” from MCC	3	Y	N
Application of safety grounds, after voltage test	2	Y	N
Removal of bolted covers (to expose bare, energized parts)	2	N	N
Opening hinged covers (to expose bare, energized parts)	1	N	N

600 V Class Switchgear (with power circuit breakers or fused switches) - Notes 5 and 6
Task (Assumes Equipment Is Energized, and Work Is Done Within the Flash Protection Boundary)	Hazard/ Risk Category	V-rated Gloves	V-rated Tools
CB or fused switch operation with enclosure doors closed	0	N	N
Reading a panel meter while operating a meter switch	0	N	N
CB or fused switch operation with enclosure doors open	1	N	N
Work on energized parts, including voltage testing	2	Y	Y
Work on control circuits with energized parts 120 V or below, exposed	0	Y	Y
Work on control circuits with energized parts >120 V, exposed	2	Y	Y
Insertion or removal (racking ) of CBs from cubicles, doors open	3	N	N
Insertion or removal (racking) of CBs from cubicles, doors closed	2	N	N
Application of safety grounds, after voltage test	2	Y	N
Removal of bolted covers (to expose bare, energized parts)	3	N	N
Opening hinged covers (to expose bare, energized parts)	2	N	N

Other 600 V Class (277 V through 600 V, nominal) Equipment - Note 3
Task (Assumes Equipment Is Energized, and Work Is Done Within the Flash Protection Boundary)	Hazard/ Risk Category	V-rated Gloves	V-rated Tools
Lighting or small power transformers (600 V, maximum)	-	-	-
Removal of bolted covers (to expose bare, energized parts)	2*	N	N
Opening hinged covers (to expose bare, energized parts)	1*	N	N
Work on energized parts, including voltage testing	2*	Y	Y
Application of safety grounds, after voltage test	2*	Y	N
Revenue meters (kW-hour, at primary voltage and current)	-	-	-
Insertion or removal	2*	Y	N
Cable trough or tray cover removal or installation	1	N	N
Miscellaneous equipment cover removal or installation	1	N	N
Work on energized parts, including voltage testing	2*	Y	Y
Application of safety grounds, after voltage test	2*	Y	N

NEMA E2 (fused contactor) Motor Starters, 2.3 kV Through 7.2 kV
Task (Assumes Equipment Is Energized, and Work Is Done Within the Flash Protection Boundary)	Hazard/ Risk Category	V-rated Gloves	V-rated Tools
Contactor operation with enclosure doors closed	0	N	N
Reading a panel meter while operating a meter switch	0	N	N
Contactor operation with enclosure doors open	2*	N	N
Work on energized parts, including voltage testing	3	Y	Y
Work on control circuits with energized parts 120 V or below, exposed	0	Y	Y
Work on control circuits with energized parts >120 V, exposed	3	Y	Y
Insertion or removal (racking ) of starters from cubicles, doors open	3	N	N
Insertion or removal (racking) of starters from cubicles, doors closed	2	N	N
Application of safety grounds, after voltage test	3	Y	N
Removal of bolted covers (to expose bare, energized parts)	4	N	N
Opening hinged covers (to expose bare, energized parts)	3	N	N

Note: V-rated Gloves are gloves rated and tested for the maximum line-to-line voltage upon which work will be done. V-rated Tools are tools rated and tested for the maximum line-to-line voltage upon which work will be done. 2* means that a double-layer switching hood and hearing protection are required for this task in addition to the other Hazard/Risk Category 2 requirements of Table 130.7(C)(10). Y = yes (required) N = no (not required) Notes:

25 kA short circuit current available, 0.03 second (2 cycle) fault clearing time.
65 kA short circuit current available, 0.03 second (2 cycle) fault clearing time.
For < 10 kA short circuit current available, the hazard/risk category required may be reduced by one number.
65 kA short circuit current available, 0.33 second (20 cycle) fault clearing time.
65 kA short circuit current available, up to 1.0 second (60 cycle) fault clearing time.
For < 25 kA short circuit current available, the hazard/risk category required may be reduced by one number.