Electrical Safety in Construction

Electrocution is the third Fatal Four cause in construction. OSHA 1926 Subpart K covers electrical safety. GFCIs (Ground Fault Circuit Interrupters) are required on all 120V, 15-20A outlets that are not part of the permanent building wiring. The Assured Equipment Grounding Conductor Program (AEGCP) is the alternative — requiring documented testing of all equipment grounding conductors. Current as low as 10-100 milliamps passing through the chest can cause cardiac fibrillation and death. Even 120V household current is potentially fatal.

Overhead power line hazards: maintain a minimum 10-foot clearance from lines rated up to 50kV. Call 811 before any excavation. De-energize or insulate lines when work must occur within clearance distances. A qualified utility company representative must be present when work is within required clearance of energized overhead lines. Ground fault protection, proper grounding, and inspection of all electrical equipment and cords are essential preventive measures. Lockout/tagout (1926 Subpart K) must be applied before maintenance work on electrical systems — de-energize, isolate, lock, and verify zero energy state.

Arc flash in construction: when a worker contacts energized conductors or creates a short circuit, an arc flash can generate temperatures exceeding 35,000°F and pressures equivalent to an explosion at the worker's position. Arc-rated PPE (face shields, clothing) is required when workers must perform work on or near energized systems. For OSHA 30 supervisors: create and enforce a site electrical safety plan, conduct pre-task briefings on electrical hazards, verify GFCI protection on all temporary power, and never allow damaged electrical equipment on site.