Everyday work clothes made from commonly used apparel fibers, including cotton, nylon and polyester (alone or in blends), are not designed to protect against a fire hazard and are not suitable flame-resistant (FR) clothing for laboratory work.
If exposed to a flame, cotton can ignite and continue to burn, while nylon and polyester can ignite, burn, melt and possibly adhere to the wearer’s skin. Everyday work clothes are inappropriate in these hazard situations; protective FR clothing for laboratory work and measures to reduce potential risk should be adopted.
Part of a general safety program
Most regulatory agencies recognize that personal protective equipment (PPE) alone cannot eliminate all risks of injury. It must be part of a general safety program. As pointed out by the U.S. Occupational Safety and Health Administration (OSHA) in Appendix B of 29 CFR 1910, Subpart I: “PPE devices alone should not be relied on to provide protection against hazards, but should be used in conjunction with guards, engineering controls, and sound manufacturing practices.”
The importance of hazard assessments
OSHA further notes in 29 CFR 1910.132, that PPE selection must be based on a workplace hazard assessment. When the hazard assessment indicates the potential for fire-related injury, suitable, lab-appropriate PPE should be selected. For example, while FR lab coats may be appropriate when the risk of fire is positioned above the wearer’s waist, lab coats may not be suitable if the fire threat comes from below the waist or from the floor. If a fire originates on the floor or around the wearer’s legs, flames and hot air can potentially flow up and under lab coats (and untucked shirts), with an increased probability of additional skin burn injury should the underclothing catch fire. In such cases, the combination of an FR shirt and FR pants, worn with the shirt tucked into the pants, or a one-piece FR coverall, should be considered to protect both the upper and lower body.
Garments to match the hazards
If the workplace hazard assessment leads to the conclusion that a threat of fire exists, garments made of FR materials, such as DuPont™ Nomex® IIIA or Protera®, should be considered. However, an FR lab coat may not provide adequate protection compared to garment-style PPE, such as coveralls, or pants and shirts (both of which provide more complete body protection), or FR chemical splash suits (such as DuPont™ Tychem® 6000 FR).
FR clothing helps to minimize potential burn injury during short-term and emergency exposure to flame. Most FR clothing is designed to provide the wearer with time to escape from the area where the fire has occurred. Protective apparel cannot prevent all burn injuries.
The protective performance of the garment ensemble can be optimized by proper selection, care, maintenance and layering. FR PPE should be cleaned and inspected on a regular basis to remove flammable contaminants and repaired to manufacturer’s specifications. In high thermal-exposure situations, garments made of nylon, polyester or polypropylene worn underneath FR PPE may melt and adhere to the skin. Garments worn under FR PPE should be made of non-melting materials to maximize thermal performance and minimize the potential for burn injury.