A r c F l A s h P r o t e c t i v e c l o t h i n g F o r n F P A 7 0 e

Arc Flash Protective clothing For nFPA 70e – 1

nFPA 70e is the national consensus

standard for electrical safety in the

Workplace.

the scope of this standard is to address safety-related work practices for the practical safeguarding of employees relative to the hazards associated with working around electrical energy. it specifically covers those electrical work practices performed by electricians and maintenance workers within a facility.

nearly all industries fall under the practices outlined in nFPA 70e. Manufacturing industries using high-voltage electrical equipment, such as aerospace, automotive, food processing, pulp & paper, industrial equipment, electronics, pharmaceuticals, and many others, are all covered by nFPA 70e. however, nFPA 70e does not cover electrical work performed outside of the facility that is under the exclusive control of an electric utility. this industry is covered by the national electrical safety code (nesc).

Many state oshA agencies use nFPA 70e as their guideline for evaluating the protection of electrical workers. those companies not protecting their employees from electric arc flash hazards as described by this standard are at risk for potential fines should a safety inspection take place or an accident occur. so compliance with nFPA 70e not only protects workers but reduces the risk of oshA fines.

this informational guide will give you a brief overview of the nFPA 70e sections related to arc flash protective clothing and other PPe.

Arc Flash Protective clothing For nFPA 70e – 32 – Workrite Uniform company inc.

Article 130 – Work Involving Electrical Hazards

this is the section within nFPA 70e that addresses the conditions under which PPe is required and the type and level of protection needed for various work conditions. it starts by stating, “energized electrical conductors and circuit parts…shall be put into an electrically safe work condition before an employee performs work…” With that said, the standard goes on to state that “energized work shall be permitted where the employer can demonstrate that de-energizing introduces additional hazards or increased risk.” it also states that “energized work shall be permitted where the employer can demonstrate that the task to be performed is infeasible in a de-energized state due to equipment design or operational limitations.”

PLUS: Equipment operating at less than 50 volts is not required to be de-energized.

Hazard Assessment

in order to determine the proper type and protection level of PPe, a hazard assessment must be performed. in addition, federal oshA requires employers to conduct hazard assessments in accordance with 29 cFr 1910.132(d). if an arc flash hazard is present, oshA deems the employer to be in compliance if nFPA 70e is the basis of determining the arc flash protection boundary and the necessary PPe.

Section 130.5 Arc Flash Hazard Analysis

A critical piece of the hazard assessment is performing an arc flash hazard analysis. this analysis is required in order to establish the arc flash boundary, the incident energy at the working distance and the PPe that people within the arc flash boundary shall use.

this section allows for the selection of the protective clothing and other PPe to be established by either performing an incident energy analysis or by using the hazard/risk category (hrc) tables established in the standard. You can determine the hazard/risk category by comparing the desired job with common tasks found in nFPA 70e table 130.7 (c)(15)(a). once the task has been identified on the table, one of five hrc numbers will be identified as appropriate for that task. each of these categories requires garments with the minimum associated arc rating and other PPe to be worn.

nFPA 70e

energized component

Flash Boundary

Within the flash boundary, a person could receive at least a second-degree

burn from an arc flash.

Fig. 1

Arc FlAsh BoUnDArY = the distance at which the incident energy equals 1.2 cal/cm². this is the energy level that will generate a second-degree burn on exposed skin.

tasks Performed on energized equipmenthazard/risk

category

rubber insulating

gloves

insulated and insulating hand tools

insertion or removal (racking) of cBs from cubicles, doors open or closed 4 n n

Application of temporary protective grounding equipment after voltage test 2 Y n

removal of bolted covers (to expose bare, energized electrical conductors and circuit parts)

4 n n

other 600 v class (277 v through 600 v, nominal) equipment

Parameters: Maximum of 65 kA short circuit current available; maximum of 0.03 sec (2 cycle) fault clearing time; minimum 18 in. working distance (exept as indicated) Potential arc flash boundary with exposed energized conductors or circuit parts using above parameters: 53 in.

lighting or small power transformers (600 v, maximum)

removal of bolted covers (to expose bare, energized electrical conductors and circuit parts)

opening hinged covers (to expose bare, energized electrical conductors and circuit parts)

Work on energized electrical conductors and circuit parts, including voltage

2

1

2

n

n

Y

n

n

Y

once the hrc number has been identified from the task table, the PPe table 130.7 (c)(16) (see page 4) shall be used to determine the requirements for the specific protective clothing and other PPe based on that hrc number. hrc 1 and 2 are typically standard work clothes that have been arc rated from between a minimum of 4 cal/cm² for hrc 1, and a minimum of 8 cal/cm² for hrc 2. When the incident energy potential reaches 25 cal/cm², hrc 3 is required; at 40 cal/cm² and greater, hrc 4 garments are required.

70E Hazard/Risk Category Classification Table

Table 130.7 (C)(15)(a)

Arc Flash Protective clothing For nFPA 70e – 54 – Workrite Uniform company inc.

hazard/risk category

clothing & PPe DescriptionMinimum Arc rating

0Protective Clothing: non-melting or untreated natural fiber at least 4.5 oz/yd²

Protective Equipment: safety glasses or goggles, hearing protection, leather glovesn/A

1

Arc-Rated Clothing: Arc-rated long-sleeve shirt and pants or arc-rated coverall, arc-rated face shield or arc flash suit hood, arc-rated jacket, parka, rainwear or hard hat liner as needed

Protective Equipment: hard hat, safety glasses or goggles, hearing protection, leather gloves, leather work shoes

4 cal/cm²

2

Arc-Rated Clothing: Arc-rated long-sleeve shirt and pants or arc-rated coverall, arc-rated face shield and arc-rated balaclava or arc flash suit hood, arc-rated jacket, parka, rainwear or hard hat liner as needed

Protective Equipment: hard hat, safety glasses or goggles, hearing protection, leather gloves, leather work shoes

8 cal/cm²

3

Arc-Rated Clothing: Arc-rated long-sleeve shirt, arc-rated pants, arc-rated coverall, arc-rated flash suit jacket, arc-rated flash suit pants, arc-rated flash suit hood, arc-rated gloves, arc-rated jacket, parka, rainwear or hard hat liner as needed

Protective Equipment: hard hat, safety glasses or goggles, hearing protection, leather gloves, leather work shoes

25 cal/cm²

4

Arc-Rated Clothing: Arc-rated long-sleeve shirt, arc-rated pants, arc-rated coverall, arc-rated flash suit jacket, arc-rated flash suit pants, arc-rated flash suit hood, arc-rated gloves, arc-rated jacket, parka, rainwear or hard hat liner as needed

Protective Equipment: hard hat, safety glasses or goggles, hearing protection, leather gloves, leather work shoes

40 cal/cm²

Section 130.7 Personal and Other Protective Equipment

this is the section that provides specific requirements for those employees working in areas where electrical hazards are present. those employees are required to be provided with and use protective equipment designed for the specific part of the body to be protected at the incident energy level, as established in the arc hazard analysis or as specified in the hrc tables.

the specific parts of the body required to be protected include:

Head, Face, Neck and Chin (Head Area) Protection non-conductive head protection whenever there is a danger from shock, contact burns or flying objects from electrical explosions. the face, neck and chin shall be protected from exposure to electric arcs or flashes and flying objects. if hairnets or beardnets are used, they must be arc rated.

Eye Protection eye protection when there is a danger from electric arcs, flashes or flying objects.

Hearing Protection hearing protection whenever working within the arc flash boundary.

Body Protection Arc-rated clothing whenever there is a possibility of exposure to an electric arc flash above an incident energy level of 1.2 cal/cm².

Hand and Arm Protection hand and arm protection as appropriate for either shock and/or arc flash as detailed in other sections.

Factors in Selection the specific factors in the selection of protective clothing are stated as: “if arc rated clothing is required, it shall cover associated parts of the body as well as all flammable apparel.” it goes on to state that “garments that are not arc rated shall not be permitted to be used to increase the arc rating of a garment or of a clothing system.”

Layering, Coverage and Fit general non-melting, flammable fiber garments are permitted to be used as under layers in conjunction with arc-rated garments for added protection. the arc rating of the system must be sufficient to prevent break-open of the innermost arc-rated layer.

Outer Layers the outermost layer, such as jackets or rainwear, must be made of arc-rated material.

Under Layers Meltable fibers such as acetate, nylon, polyester, polypropylene and spandex are not permitted in fabric under layers (underwear) next to the skin.

Coverage clothing must cover potentially exposed areas as completely as possible.

Fit tight-fitting clothing should be avoided. loose-fitting clothing provides additional insulation because of air spaces.

Interference the garment should have the least interference with the task but still provide the necessary protection.

70E Hazard/Risk Category Classification Table (Cont.)

Table 130.7 (C)(16)

Arc Flash Protective clothing For nFPA 70e – 76 – Workrite Uniform company inc.

Simplified Choices with Two Clothing Sets

though different clothing is specified for each arc-rating minimum, many companies simplify their needs by choosing just two sets of clothing for their people to handle all electrical tasks:

(a) a garment set with an arc rating of at least 8 cal/cm² for the more routine tasks of hrc 0, 1 and 2

(b) a garment set with an arc rating of at least 40 cal/cm² for more specialized tasks of hrc 3 and 4

Standards on Protective Equipment

table 130.7(c)(14) lists the various performance standards, to which the protective clothing and PPe needs to conform.

PPe type Document number Document title

Apparel – Arc rated AstM F1506

standard Performance for Flame-resistant and Arc-rated textile Materials for Wearing Apparel for Use by electrical Workers exposed to Momentary electric Arc and related thermal hazards

eye and Face – general Ansi/Asse Z87.1Practice for occupational and educational eye and Face Protection

Face – Arc rated AstM F2178standard test Method for Determining the Arc rating and standard specification for Face Protective Products

gloves – leather Protectors AstM F696standard specification for leather Protectors for rubber insulating gloves and Mittens

gloves – rubber insulating AstM D120 standard specification for rubber insulating gloves

head Protection – hard hat Ansi/iseA Z89Personal Protection – Protective headwear for industrial Workers

rainwear – Arc-rated AstM F1891 standard specification for Arc- and Flame-resistant rainwear

So What Role Can Arc-Rated Clothing Play?

Arc-rated clothing:

• Does not ignite or continue to burn

• Provides a protective barrier against the arc flash

• Insulates the wearer from heat

Why is this important?

• Most severe burns are caused by ignited clothing rather than by the original hazard.

• Clothed areas can be burned more severely than skin that is exposed directly to the arc flash. this is because the initial exposure is of a short duration while the burning clothing continues to apply heat to the skin until it either goes out or is removed.

• The long-term cost of a single burn injury can exceed the cost of an entire Fr clothing program.

• Rehabilitation for burn injuries can be extremely long and painful.

Arc-rated clothing is worn as insurance. In the unlikely event of an arc flash, these garments:

• Minimize or reduce burn injury

• Increase chances of survival

Summary

each year, more than 2,000 employees are admitted to burn centers with severe burns resulting from arc flash accidents. Manufacturing facility workers within the arc flash boundary are at risk of being exposed to an arc flash event while performing common electrical work on energized parts or equipment. Because of that, being in compliance with the nFPA 70e safety standard not only protects those workers but reduces the risk of fines to the company should an accident occur.

Surviving a Flash Fire

20-29

100

75

50

25

0

25% Body Burn

50% Body Burn

75% Body Burn

% Survival

Age Groups

Burn Survival Rate

30-39 40-49 50-59

corporate office 1701 North Lombard Street, Suite 200 • Oxnard, California 93030

800/521-1888 • 805/483-0175 • Fax 805/483-0678

www.workrite.com

10/17/12

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flame-resistant apparel for working men and women.