Temporary lighting needs to follow the work as access routes, partitions and installations change. Plan illumination and electrical distribution together, then check the result at the task rather than assuming a fixture count establishes compliance.
Use the correct illumination category
OSHA 1926.56 Table D-3 gives different minimum levels for different areas and operations. General construction lighting, specific outdoor work areas, indoor routes, shops and first-aid areas do not all use the same value. Use the applicable row, including the special tunnel-heading provision where relevant.
Measure the working area with a suitable meter. Obstructions, mounting height and the location of the task can make a room-average reading unrepresentative of the place where someone is working.
Protect lamps and cables
OSHA's temporary-wiring requirements address protection against lamp breakage, grounded metal-case sockets, hard or extra-hard usage cords and cable protection. Lights must not hang by their cords unless designed for that suspension. Route cables away from sharp edges, door pinch points and moving equipment.
Treat wet or conductive work separately
For construction portable lighting in wet or conductive locations such as drums, tanks and vessels, 1926.405(a)(2)(ii)(G) specifies 12V or less, with a stated alternative for 120V lighting protected by a GFCI. This is not a blanket 24V allowance. The light and connections must also suit the exposure and any classified-area requirements.
Recheck as the build changes
Review shadows after walls, services and equipment are installed. Maintain supports, guards, lenses and cords, and keep lighting circuits and protective devices identifiable. A defective lamp should be removed from service rather than patched with an unapproved substitution.
Guirlande lumineuse cover successive work positions; portable task lights serve smaller repairs and installations. Choose the format after establishing the electrical and illumination requirements.
References: OSHA 1926.56 — Construction illumination · OSHA 1926.405 — Temporary wiring and portable lighting