Night worker

Regular night work triggers extra protection

A night worker regularly works at least three hours during night time. In Great Britain, the default night period is 11pm to 6am, although a valid agreement can set a different seven-hour period that includes midnight to 5am. Occasional late work does not automatically make someone a night worker.

Adult night workers must not exceed an average of eight hours' work in each 24-hour period, normally measured over a reference period. Where night work involves special hazards or heavy physical or mental strain, the eight-hour limit applies to each 24 hours and cannot be averaged. A worker cannot opt out of night-work limits.

The Acas night-worker guidance explains the test and limits. Young workers have separate, stricter restrictions.

Offer health assessments and respond to risk

Offer a free health assessment before someone starts night work and repeat it at appropriate intervals. The worker can decline, but the offer and any follow-up should be recorded confidentially.

If a health professional confirms that night work has affected a worker's health, find them other suitable work where possible. Assess the wider fatigue risk as well: consecutive nights, long commutes, workload, lone working and quick returns between shifts can matter even when the hours fall inside the statutory ceiling.

Review a night rota when shifts lengthen, overtime rises or workers swap frequently. The average can hide a tiring sequence that still needs a health-and-safety response.

Keep the category and hours visible

Record who meets the night-worker test, the night period used, actual hours, health-assessment offers and any hazardous-work classification. Keep the evidence for the required period rather than relying on published rotas alone.

Check Northern Ireland night work under its own regulations. Similar headline numbers do not make the Great Britain legislation UK-wide.