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Construction Safety & OSHA

Electrical & Lockout/Tagout

Electrocution is one of OSHA’s Focus Four, and most jobsite shocks trace back to a few avoidable mistakes.

Temp-power protection: GFCI (or assured grounding program) · Overhead lines (≤50 kV): stay 10 ft clear · Before service: lockout/tagout · Tools: grounded or double-insulated · Cords: 3-wire grounding type, undamaged · Assume: every conductor is energized until verified.

Temporary power

  • Construction receptacles need GFCI protection, or an assured equipment grounding conductor program.
  • Use three-wire grounding extension cords; never use a cord with damaged insulation, and keep cords out of water and walkways.
  • Power tools must be grounded or double-insulated.

Working safely

  • Keep 10 feet from overhead lines ≤50 kV (more for higher voltages).
  • Lock out and tag out equipment before servicing it, and verify zero energy.
  • Assume conductors are live until they’re tested and confirmed de-energized — most fatal shocks come from “dead” circuits that weren’t.

Practice: Electrical & Lockout/Tagout

Frequently asked

What protects workers from shock on temporary construction power?
A ground-fault circuit interrupter (GFCI) on 120-volt receptacles (29 CFR 1926.404). If GFCIs aren't used, the employer must run an assured equipment grounding conductor program instead.
How far must you stay from overhead power lines?
At least 10 feet for lines rated 50 kV or less; add 4 inches for every additional 10 kV above 50 kV. Treat every line as energized until the utility confirms otherwise.

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