Which organization sets the primary safety standard for arc flash protective clothing in the United States?

The organization that sets the primary safety standard for arc flash protective clothing in the United States is the National Fire Protection Association (NFPA). The NFPA develops codes and standards aimed at preventing fire and electrical hazards, including those related to arc flash incidents.

One of the key standards created by NFPA is NFPA 70E, which specifically addresses electrical safety in the workplace and provides guidelines for the selection and use of personal protective equipment, including clothing designed to protect against arc flash hazards. This standard is particularly crucial as it helps employers ensure that their workers are adequately protected from electrical risks that can lead to severe injuries.

While other organizations like OSHA and NIOSH play significant roles in overall workplace safety, OSHA sets regulations and enforces standards related to workplace safety, and NIOSH primarily focuses on research and recommendations pertaining to occupational safety and health. ASTM is involved in developing voluntary consensus technical standards for materials, products, systems, and services, but it does not set the primary safety standard for arc flash protective clothing. Therefore, the NFPA is recognized as the authoritative body in this area, making it the correct choice.