OSHA 29 CFR 1926 Subpart K — Electrical (Construction) — Compliance Brief
Record: electrical-power-cert-020 (Electrical/Power — regulation, flagship)
Issuing body / enforcer: U.S. Occupational Safety and Health Administration (OSHA), Department of Labor; state-plan states enforce equivalents
Jurisdiction: United States, federal — construction sites. Companion to 29 CFR 1910 Subpart S (general industry); the two are mutually exclusive by work type, not by employer.
1. What it is
Subpart K is OSHA's electrical-safety standard for construction work: installation, alteration, and maintenance of electrical systems on construction sites, plus the protection of construction workers from electrical hazards generally. Where 1910 Subpart S governs the finished workplace, 1926 Subpart K governs the building of it — temporary wiring, temporary lighting, extension cords, portable tools, and the particular hazards of unfinished installations (missing covers, exposed conductors, wet conditions, energized work during commissioning).
The standard's structure: general requirements (§1926.400), wiring design and protection (§1926.403–408 — closely tracking the NEC), wiring methods and equipment (§1926.405), and safety-related work practices (§1926.416 — qualified vs. unqualified persons, alerting techniques, and the construction-specific rules for working near energized parts).
2. Scope — who/what it applies to, triggers
- Applies to: construction employers and employees exposed to electrical hazards on construction sites — including electrical contractors, general contractors (multi-employer duties), and any trade working near electrical installations.
- Key construction-specific triggers:
- Temporary wiring (§1926.405(a)(2)): construction sites run on temporary power — the standard sets specific rules for it (feeders, branch circuits, receptacle requirements) that don't exist in general industry.
- GFCI or assured equipment grounding conductor program (§1926.404(b)(1)): all 120V, single-phase, 15/20A receptacle outlets on construction sites not part of permanent wiring must have GFCI protection or the employer must run a documented assured grounding program with periodic testing. This is stricter than general industry and is one of the most-cited provisions in construction.
- Overhead power line clearances (§1926.416 and related): cranes, scaffolds, and equipment operating near overhead lines — electrocution from line contact is a leading construction fatality cause.
- Does not cover: work already covered by 1910.269 (utility power generation/transmission/distribution) or 1910 Subpart S (general industry). Power-line construction has its own standard (§1926 Subpart V).
3. Key requirements and compliance obligations
- GFCI/assured grounding as above — the practical choice is nearly always GFCI; assured-grounding programs require documented daily/periodic inspections and testing that most contractors find harder to sustain.
- Grounding of equipment: non-current-carrying metal parts of equipment must be grounded; grounding-path continuity on temporary systems.
- Flexible cords and cables: strict limits — cords can't be run through holes in walls/ceilings/floors, can't be used as substitutes for fixed wiring, must be protected from damage; splices must retain insulation and strain-relief properties.
- Boxes, cabinets, and fittings: covers required; unused openings closed; equipment must be firmly secured.
- Work practices (§1926.416): alerting techniques (safety signs, barricades, attendants) for unqualified persons near exposed energized parts; qualified persons may work within limited approach distances only with proper training and PPE; overhead line minimum clearances — generally 10 feet up to 50 kV, plus 4 inches per additional 10 kV (verify against current table; the crane standard §1926.1408–1411 has its own detailed clearance regime).
- Lockout/tagout in construction: construction has no direct equivalent of §1910.147's full LOTO standard; Subpart K's §1926.417 addresses lockout/tagging of circuits during work, and NFPA 70E provides the detailed practice. This gap is a known compliance trap — contractors must still implement effective hazardous-energy control.
- Lighting: adequate illumination; temporary lights guarded against breakage where exposed to contact.
4. Penalties / consequences of non-compliance
- Same OSHA penalty structure as general industry (inflation-adjusted annually — recent magnitudes ~$16,500/serious, ~$165,000/willful or repeated; verify current figures). Construction inspections are heavily driven by complaints, referrals, fatalities, and targeted programs (e.g., trenching, falls, and electrical emphasis programs).
- Criminal exposure: willful violations causing death can be referred for criminal prosecution; several high-profile contractor prosecutions have involved electrical fatalities.
- Multi-employer liability: GCs and subs are independently citable; the controlling-employer doctrine is litigated constantly in construction.
- Electrocution remains a top construction fatality cause (power-line contact, defective equipment/grounding, improper use of cords) — the human cost is the compliance driver more than the fine schedule.
5. Version / edition status and live changes (verified to 2026-09-30)
- Subpart K is a stable regulation; no structural revision verified in 2025–2026.
- Live interaction — NEC 2026 and 70E: the 2026 NEC's expanded arc-flash labeling and the ongoing NFPA 70E revision cycle affect construction commissioning and energized-work practices directly (contractors performing energized testing/startup on new installations). Update energized-work procedures and PPE assessments in step with the 2026 NEC adoption in your AHJ.
- Enforcement emphasis: OSHA's construction electrical citations concentrate on GFCI/grounding (§1926.404), wiring methods (§1926.405), and overhead-line clearances — these three areas account for the bulk of Subpart K citations. No 2025–2026 Subpart K rulemaking verified — flagged as no-change found.
6. Related certifications (same-discipline, license/flagship, from the catalogue)
- State Master/Journeyman Electrician License (
electrical-power-cert-007) — construction electricians are the primary regulated population; licensing exams and apprenticeship curricula are built around NEC + Subpart K work practices. - Professional Engineer (PE), Electrical and Computer: Power (
electrical-power-cert-001) — design of temporary power systems, short-circuit/coordination for construction power, commissioning procedures. - NICET Electrical Power Testing (
electrical-power-cert-003) — acceptance/commissioning testing (standard-practice importance; named per task brief example). - Chartered Engineer (CEng) via IET (
electrical-power-cert-002) — no OSHA nexus.
7. Honest flags
- Penalty figures are inflation-adjusted annually — verify current OSHA penalty levels before quoting; figures here are recent magnitudes.
- The construction LOTO "gap" (no §1910.147 equivalent) is widely discussed in safety practice; employers should implement NFPA 70E-based hazardous-energy procedures rather than treating the absence as permission.
- Overhead-line clearance numbers summarized above are the general Subpart K rule; crane operations follow the more detailed §1926.1408–1411 regime — use the applicable standard for the equipment at hand.
- 1910 vs. 1926 boundary disputes (maintenance vs. construction) are fact-specific and frequently litigated; when in doubt, the more protective interpretation governs practice.
Original ETS reference writing, verified against public sources on 2026-09-30. Thin sourcing is flagged inline. Not legal advice — confirm current editions with the issuing body.