Electrical Safety
Electrocution is the third leading cause of death in construction, part of OSHA's 'Fatal Four.' Electrical hazards include electrocution (death from electrical current), electric shock (non-fatal current passage through the body), arc flash and arc blast (intense light and pressure wave from electrical faults), and electrical fires. OSHA 1926 Subpart K governs electrical safety in construction. Understanding how to recognize and control electrical hazards is essential for all construction workers, not just electricians.
Ground Fault Circuit Interrupters (GFCIs) are required on all 120-volt, 15- and 20-ampere outlets on construction sites that are not part of the building's permanent wiring. A GFCI detects even a small current imbalance (5 milliamps) and trips within 1/40 of a second — fast enough to prevent electrocution. Alternatively, employers can use the Assured Equipment Grounding Conductor Program (AEGCP), which requires designated personnel to inspect and test all equipment grounding conductors with documented results. Both methods are acceptable, but GFCIs are simpler and preferred. Extension cords must be rated for the application (outdoor/indoor), must not be damaged (no cuts, exposed conductors, damaged plugs), and must not be routed through doors, windows, or other pinch points that could damage insulation.
Work near overhead power lines is a leading cause of electrocution in construction. The minimum clearance for unqualified workers and equipment is 10 feet from lines rated up to 50kV. Before any excavation work, call 811 (the national 'call before you dig' number) to have underground utilities located and marked. Lockout/tagout (LOTO) in construction controls hazardous energy when performing maintenance or repair. Before working on any electrical equipment, the circuit must be de-energized, the disconnect locked in the off position, and the energy-isolating device tested to verify zero energy state. Arc flash — the explosive release of energy from an electrical fault — can cause severe burns at distances of several feet; appropriate PPE includes arc-rated face shields and clothing when working on energized equipment.