Electrical Safety in General Industry
Electrical hazards kill approximately 300 workers annually in general industry and injure thousands more. OSHA's electrical safety standards for general industry are found in 29 CFR 1910 Subpart S, covering wiring design and protection, wiring methods, equipment, and safety-related work practices. NFPA 70E (Standard for Electrical Safety in the Workplace) provides more detailed guidance on arc flash protection and safe work procedures around energized electrical equipment. Supervisors must ensure workers do not work on energized systems unless de-energizing creates greater hazards or is infeasible, and then only with proper permits and PPE.
The four electrical hazards are shock, arc flash, arc blast, and fire. Electrical shock occurs when current passes through the body — as little as 50 milliamps can cause cardiac arrest. The severity depends on current magnitude, path through the body, and duration. Ground Fault Circuit Interrupters (GFCIs) protect against shock by detecting current leakage of 4-6 milliamps and interrupting the circuit in 1/40th of a second. GFCIs are required in construction, outdoor outlets, wet locations, kitchens, bathrooms, and any location where water contact is possible.
Arc flash occurs when current travels through the air between conductors or between a conductor and ground, releasing massive amounts of energy as heat, light, and pressure. Arc flash temperatures can reach 35,000°F — four times the surface temperature of the sun. NFPA 70E requires an arc flash hazard analysis to determine the incident energy at a worker's position, establish arc flash boundaries (Flash Protection Boundary, Limited Approach Boundary, Restricted Approach Boundary), and select appropriate arc-rated (AR) PPE. Workers must wear AR clothing rated in calories per square centimeter (cal/cm²) that equals or exceeds the calculated incident energy.
Extension cord safety is a frequent OSHA citation. Key rules: extension cords are for temporary use only (not substitutes for permanent wiring), must be rated for the load they carry (check ampacity), must not be run under rugs or through walls or ceilings, must not be daisy-chained, must be inspected before each use and removed from service if insulation is damaged, and must be three-wire (grounded) when used with grounded equipment. Power strips with surge protection are not the same as industrial multi-outlet assemblies and have limited use in industrial settings.