Historically, the National Electric Code (NEC.) and other safety codes were primarily concerned with protection from fire, electrocution, and shock hazard—arc flash hazards were not addressed. This changed in 2002, when NEC included requirements for warning labels. The National Fire Protection Association (NFPA.) is responsible for the NEC.
Since the NEC was concerned mainly with electrical design, construction, and inspection, it could not be adopted by employers and employees with regard to implementing standards for workplace safety. To bridge this gap, a new standard, NFPA 70E, Standard for Electrical Safety Requirements for Employee Workplaces,10 was developed. NFPA 70E is intended for use by employers, employees, and the Occupational Safety and Health Administration (OSHA). The publication NFPA 70E-2015 includes arc flash hazard as a potential danger to workers near and around live exposed electrical parts. NFPA 70E and IEEE Std 1584-2002 provide guidance on implementing appropriate safety procedures and arc flash calculations.
NEC Article 110.16 requires "field marking" of potential arc flash hazards for panels likely to be serviced or examined in an energized condition. This article also contains a fine print note (FPN) regarding proper signage and an FPN referencing NFPA 70E. These FPNs are not technically part of the NEC, but are recommended practices.
OSHA has not specifically addressed arc flash hazards; however, there exists adequate safety requirements for employers to follow to ensure the safety of the worker in the workplace (General Duty clause). Some of these are outlined in Table 6.1 in Chapter 6. The Code of Federal Regulations (Standards – 29 CFR) Part 1910 deals with occupational safety and health standards. Standards on personal protective equipment (PPE) are outlined in subpart 132. In response to an inquiry on OSHA’s stand on arc flash hazard, Richard S. Terrill, the Regional Administrator for Occupational Safety and Health, US.