What Is a Night Worker?
A night worker regularly works at least 3 hours during night time. What the Working Time Regulations require for them.
A night worker, under regulation 2 of the Working Time Regulations 1998 (WTR), is a worker who, as a normal course, works at least three hours of their daily working time during "night time". A worker can also be a night worker where a collective or workforce agreement says a set proportion of their annual working time is night work.
Night time is a period of at least seven hours that includes midnight to 5am. A relevant agreement, such as a written agreement between the worker and employer or a collective agreement, can set the exact period. If nothing has been agreed, night time is 11pm to 6am.
Night workers get extra protection on top of the usual limits on weekly hours and rest breaks. Their normal hours must not exceed an average of 8 hours in each 24-hour period. The average is usually worked out over 17 weeks, or over up to 52 weeks where a collective or workforce agreement says so. Regular overtime counts towards the average; occasional overtime does not. Unlike the 48-hour weekly limit, workers cannot opt out of the night work limit. Where the work involves special hazards or heavy physical or mental strain, the limit is an absolute 8 hours in any 24 hours in which night work is done. Before someone becomes a night worker, and regularly afterwards, the employer must offer a free health assessment.
These rules apply to an agency worker from day one of an assignment. The WTR covers agency workers directly, and where there is no worker's contract with either the agency or the hirer, regulation 36 treats whichever of them pays the worker as the employer. AWR's 12-week qualifying period is a separate matter: it only adds the hirer's own, often more generous, terms on working time once the worker qualifies.
Young workers (over school leaving age and under 18) have separate rules: they cannot usually work between 10pm and 6am, and never between midnight and 4am, subject to sector exceptions. Gov.uk's night working hours guide sets out the rules in plain English. The rules above apply in England, Wales and Scotland.