Electric power transmission rules

Yes — 1926 Subpart V covers the construction of electric transmission and distribution lines and equipment. See the Electric Power Transmission and Distribution standard (1926 Subpart V) for the scope and title of the subpart. OSHA has also explained that work on the supply side of the service point may fall under either construction rules (Subpart V) or operations/maintenance rules (see the interpretation on temporary underground cable practices at Temporary underground cable practices (2005-11-22)).

No — underground electrical transmission and distribution lines are excluded from Subpart S and are addressed in Subpart V. OSHA clarified that Subpart S explicitly excludes "underground electrical transmission and distribution lines, as addressed in Subpart V of" Part 1926 in the letter about lone workers in tunnels: Lone workers in underground tunnels (2001-05-03). See the Electric Power Transmission and Distribution standard (1926 Subpart V) for the applicable construction standard.

OSHA does not have a Subpart V rule that expressly prohibits or sets a specific time limit for leaving a 7,200‑volt underground cable laid on the ground as temporary wiring, but the practice can create hazards that may lead to enforcement. OSHA's interpretation on this exact practice states that either 1910.269 or Subpart V would apply depending on the work, and that neither standard expressly forbids prolonged use of the temporary wiring; however, OSHA may cite under the General Duty Clause if the practice creates a recognized hazard (Temporary underground cable practices (2005-11-22)).

Yes — OSHA can use the General Duty Clause (Section 5(a)(1)) to cite an employer if the temporary wiring creates a recognized hazard and the four General Duty criteria are met. OSHA explicitly stated in its interpretation that when standards do not directly address a hazard, the agency may issue a citation under the General Duty Clause if the hazard is recognized, likely to cause serious harm, and there is a feasible way to abate it (Temporary underground cable practices (2005-11-22)). See the Electric Power Transmission and Distribution standard (1926 Subpart V) for the construction-specific rules that apply to these works.

No — OSHA does not directly enforce NFPA 70E as a regulation, but OSHA may consider NFPA 70E as evidence of a recognized industry practice or hazard and may use it in enforcement decisions. OSHA explained this relationship and how industry consensus standards inform enforcement and multi-employer citation decisions in its letter about NFPA 70E and the multi-employer policy (NFPA 70E and multi-employer policy (2003-07-25)). Also consult the Electric Power Transmission and Distribution standard (1926 Subpart V) for applicable regulatory requirements.

Under OSHA’s multi-employer policy an employer may be cited if it fits one of four roles: exposing (employees exposed), creating (creating the hazard), correcting (hired to correct the hazard), or controlling (has supervisory authority at the site). The compliance officer then reviews whether the employer took sufficient steps to meet its obligations before issuing a citation. OSHA described this multi-employer analysis when discussing NFPA 70E and related enforcement (NFPA 70E and multi-employer policy (2003-07-25)). Also review the Electric Power Transmission and Distribution standard (1926 Subpart V) for the applicable construction duties.

Owners are not automatically strictly liable, but they can be cited under OSHA’s multi-employer policy if they are a "controlling" employer or otherwise meet one of the roles (exposing, creating, correcting, controlling) and they failed to take sufficient steps to meet their obligations. OSHA discussed owner responsibilities and NFPA 70E in the NFPA 70E/multi-employer interpretation (NFPA 70E and multi-employer policy (2003-07-25)). Employers and owners should follow the Electric Power Transmission and Distribution standard (1926 Subpart V) and consider consensus practices to reduce recognized hazards.

Yes — OSHA may consider industry codes such as the National Electrical Safety Code (NESC) as evidence that a hazard is recognized and that feasible abatement measures exist. In the temporary underground cable interpretation OSHA cited NESC Rule 014A3, noting the NESC statement that "Emergency installations shall be removed, replaced, or relocated, as desired, as soon as practical," which supports the view that prolonged temporary installations carry additional risk (Temporary underground cable practices (2005-11-22)). See the Electric Power Transmission and Distribution standard (1926 Subpart V) for regulatory requirements.

Take reasonable abatement measures such as removing, replacing, or relocating the temporary cable as soon as practicable and inspecting for insulation damage; document the hazard assessment and repairs. OSHA’s temporary-cable interpretation specifically notes that industry guidance (for example NESC Rule 014A3) and feasible abatement (remove/replace/relocate) are relevant to whether a General Duty citation is appropriate (Temporary underground cable practices (2005-11-22)). Also follow the Electric Power Transmission and Distribution standard (1926 Subpart V) for construction-specific controls.

Work may be covered by either 29 CFR 1910.269 (operations and maintenance) or 1926 Subpart V (construction) depending on whether the activity is operation/maintenance of power systems versus construction of transmission and distribution lines; OSHA indicated that work on the supply side of the service point could fall under either 1910.269 or Subpart V in its temporary cable interpretation (Temporary underground cable practices (2005-11-22)). For construction activities use the Electric Power Transmission and Distribution standard (1926 Subpart V).

No — Subpart S check-in/check-out requirements apply to underground construction covered by Subpart S, but Subpart S expressly excludes underground electrical transmission and distribution lines, which are covered by Subpart V. OSHA clarified this exclusion in the lone-workers letter: Lone workers in underground tunnels (2001-05-03). See the Electric Power Transmission and Distribution standard (1926 Subpart V) for the rules that govern underground electrical work.

Yes — OSHA may consider consensus industry standards (for example NESC or NFPA 70E) as evidence that a hazard is recognized by the industry and that abatement methods are feasible. The temporary underground cable interpretation discusses using NESC guidance as evidence of an industry-recognized hazard (Temporary underground cable practices (2005-11-22)), and the NFPA 70E letter discusses how OSHA treats consensus standards in enforcement (NFPA 70E and multi-employer policy (2003-07-25)). Also consult the Electric Power Transmission and Distribution standard (1926 Subpart V).

OSHA advises that emergency temporary installations should be removed, replaced, or relocated "as soon as practical," and that prolonged use may increase the risk of insulation damage and other hazards. The temporary underground cable interpretation cites NESC Rule 014A3 and warns that the industry recognizes the enhanced risk from prolonged temporary installations, which can lead to General Duty enforcement if not addressed (Temporary underground cable practices (2005-11-22)). For construction-specific obligations consult the Electric Power Transmission and Distribution standard (1926 Subpart V).

A controlling employer is expected to take reasonable steps to discover and correct hazards, including periodic inspections and ensuring subcontractors follow applicable safety requirements; OSHA’s multi-employer policy explains the factors used to evaluate whether a controlling employer met its responsibilities (NFPA 70E and multi-employer policy (2003-07-25)). Apply those oversight expectations alongside the Electric Power Transmission and Distribution standard (1926 Subpart V) when supervising electrical construction work.