Jobsite Safety, Tools and OSHA Requirements
What the exam targets
OSHA construction standards (29 CFR 1926 Subpart K), NFPA 70E, temporary wiring on sites, lockout/tagout, PPE, ladders and scaffolds, and the safety ratings of test instruments.
Concepts to own
- 1926.404(b)(1): all 120 V, 15 and 20 A receptacle outlets on construction sites require GFCI protection, or an assured equipment grounding conductor program with documented tests. NEC 590.6 mirrors this for temporary installations.
- Fall protection is required at 6 ft in construction (1926.501). Ladders extend 3 ft above the landing and are set at a 4:1 ratio; scaffold fall protection triggers at 10 ft.
- Lockout/tagout (1910.147): de-energize, verify, lock, tag, and try. Only the person who applied the lock removes it.
- NFPA 70E: limited, restricted, and prohibited shock approach boundaries plus the arc-flash boundary; PPE is selected from incident energy or the tables; qualified persons are trained and retrained.
- Instrument safety: CAT III for feeders and panelboards, CAT IV at the service. The meter's rating must exceed the available fault current.
Traps
Using 10 ft as the fall-protection trigger (it is 6 ft for construction); assuming a GFCI replaces the equipment grounding conductor; treating anyone holding tools as a qualified person; forgetting the assured grounding program intervals - 3 months for cords and cord sets, 6 months for receptacles.
Rule of thumb
De-energize, test, and lock out before touching conductors. If you cannot confirm the meter's CAT rating exceeds the available fault current, do not use that meter.
Worked example
A 120 V cord-and-plug saw is used on a wet concrete slab. It must be fed from a GFCI-protected receptacle, or the site must run a documented assured equipment grounding conductor program with the required periodic testing and records.