Night Works & After-Hours Construction SWMS

Night works and after-hours construction covers any scheduled building, civil, or infrastructure activity performed between dusk and dawn, typically to reduce daytime traffic disruption, meet shutdown windows, or accelerate program. The work environment fundamentally changes after dark: ambient light disappears, peripheral vision narrows, circadian rhythms suppress alertness, and the support infrastructure (first aid, emergency services, supervisors) operates at reduced capacity. Under WHS Regulation 2025, night construction is classified as high-risk construction work when it involves powered mobile plant, work near traffic, or work at heights — all of which become materially more dangerous under artificial lighting. A documented SWMS is mandatory before any night shift commences, must address lighting design to AS/NZS 1680.3:1999, fatigue management aligned to the Safe Work Australia Managing Psychosocial Hazards CoP 2022, and noise curfew compliance under state EPA regulations. The SWMS must be signed by every worker on shift and reviewed if conditions change mid-shift.

Hazards identified

7 hazards covered, sorted by priority.

Control measures

Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.

1. 1Elimination — Reschedule non-critical tasks (concrete cutting, deep excavation, hot works) to daylight hours where program allows, eliminating night exposure entirely
2. 2Elimination — Cease all work during designated curfew windows for noise-generating plant in accordance with state EPA approved noise management plan
3. 3Substitution — Replace diesel light towers with quieter LED solar-hybrid units to substitute lower-noise, lower-emission illumination meeting AS/NZS 1680.3:1999
4. 4Substitution — Substitute traditional reversing alarms with broadband white-noise alarms to reduce community noise impact while maintaining worker warning function
5. 5Engineering — Deploy lighting plan delivering minimum 160 lux general work area and 320 lux on detailed tasks, with overlapping coverage eliminating shadow zones
6. 6Engineering — Install physical barriers and illuminated exclusion zones between mobile plant operating paths and pedestrian walkways with reflective delineators
7. 7Administrative — Cap shift length at 10 hours with mandatory 30-minute breaks every 4 hours and fatigue self-assessment at pre-start and 02:00 toolbox
8. 8Administrative — Maintain two-way radio communication on dedicated channel, with supervisor confirming worker location every 30 minutes during isolated tasks
9. 9Administrative — Brief emergency response plan at sign-on including ambulance access route, nearest after-hours hospital, and on-site first aider contact
10. 10PPE — Class D/N high-visibility garments with retroreflective tape to AS/NZS 4602.1, hard hat-mounted LED task lamps, and thermal layers for cold-weather shifts

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

On a suburban arterial road resurfacing project running 20:00 to 05:00 under a council-approved night works permit, the shift supervisor opens the pre-start brief at 19:45 by walking the crew through this SWMS at the site office demountable. He points to the lighting plan, showing where the four 9-metre LED towers must be positioned to deliver 160 lux across the milling zone with no operator-blinding glare angles toward the traffic controller. The paver operator flags during sign-on that he worked a day shift the day before — the supervisor consults the fatigue control in the SWMS, reassigns him to spotter duties, and brings in the backup operator. Each worker initials the sign-on register acknowledging the noise curfew clause: rock breaking ceases at 23:00, only low-noise compaction continues after that. At 02:30, ambient temperature drops to 4°C and a worker reports numb fingers handling survey equipment; the supervisor pauses work, references the cold stress PPE clause, issues thermal liners from the site container, and logs the mid-shift control adjustment on the SWMS review page. The amended document is re-signed by affected workers before resuming. At shift end, the signed SWMS is filed in the project HSE register where it remains accessible for the regulator and retained for the statutory minimum period.

Related legislation

• WHS Act 2011 (model)
• WHS Regulation 2025
• Code of Practice — Hazardous Manual Tasks

Frequently asked questions