Fire Resistant Clothing

DOE-HDBK-1092-98

7.4.8 FIRE RESISTANT CLOTHING

29 CFR 1910.269(l)(6)(iii)1 states, in part, "...each employee who is exposed to flames or electric

arcs does not wear clothing that, when exposed to flames or electric arcs, could increase the extent

of injury that would be sustained by the employee."

"Note: Clothing made from the following types of fabrics, either alone or in blends, is prohibited

by this paragraph, unless the employer can demonstrate that the fabric has been treated to withstand

the conditions that may be encountered or that the clothing is worn in such a manner as to eliminate

the hazard involved: acetate, nylon, polyester, rayon."

7.4.8.1 GENERAL

All fire resistant fabrics comply with 29 CFR 1910.269(l)(6)(iii). Untreated cotton and wool comply

if the fabric will not ignite and continue to burn under the conditions to which the employee could

be exposed. ASTM F1506-94 and 2 new ASTM provisional standards, outline the testing procedures

to determine how various fabrics react in the presence of an electric arc on an instrumented mannikin

or panel. The new ASTM provisional standards provide testing procedures that expose untreated and

fire resistant fabrics to electric arcs. F1506-94 provides testing procedures that expose these same

fabrics to a vertical flame test. Also see NFPA 70E, Part II, Ch. 2-3.3.3 for details on flash hazard

analysis.

7.4.8.2 ELECTRIC ARC HAZARDS

Electric shock is a widely recognized hazard and involves current flow through or on the body. Burns

from electric arcs are not as well recognized. There is no contact required and the burns can be severe

if the clothing ignites or melts. The hazards to which the employee is exposed also include the

clothing breaking open due to the arc pressure blast, the heat from the electric arc and subsequent

secondary fires or explosions.

The extent of the employees' injury is dependent on the length of the arc gap, available fault current,

duration of the arc, the distance of the employee from the arc, percentage of the body burned, the

employees age, medical condition, and number of layers of the clothing system. The proper clothing

system will minimize or reduce the burn injury.

7.4.8.3 TYPES OF FIRE RESISTANT FABRICS

Chemically dependent fire resistant fabrics are treated with flame retardant chemicals added to the

fiber or treatments applied to the fabric. These treatments are activated by heat and produce gases

that smother the flame. Typically, these fabrics have a definite life as defined by the manufacturer.

This is usually defined by the number of home or commercial washings the garment is exposed.

Inherently fire resistant fabrics, by their composition, do not burn in air. The fire resistance of this

fabric is not affected by washing.

See Appendix D, Reference Matrix.

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