1. Hours and limits

If someone works at night, there are rules covering the hours they work.

Before someone starts working at night, they must be offered a free health assessment.

Night time hours and limits

Night time working hours are usually between 11pm and 6am - but this can be flexible if agreed between workers and the employer.

The agreement must be in writing. The night time period must:

  • be 7 hours long
  • include the period between midnight and 5am

Staff who regularly work for at least 3 hours during this period are night workers. Staff may also be night workers if:

  • there’s a collective agreement (between the employer and the workers or their representatives) that states what counts as night work
  • it’s likely that they’ll work a proportion of their annual working time during the night

The rules about how long staff work at night are based on average working time, which is usually calculated over a 17-week period. This includes regular overtime but not occasional overtime.

If the workers and the employer both agree as part of a collective or workforce agreement, the working hours can be averaged over a longer period, eg up to 52 weeks.

Employers must make sure that workers don’t work more than an average of 8 hours in a 24-hour period. Workers can’t opt out of this working limit.

Employers must keep records of night workers’ working hours to prove they aren’t exceeding night working limits. Employers must keep the records for at least 2 years.

Workers shouldn’t be discriminated against because they refuse to work nights.

Young workers and staff dealing with special hazards

Some workers must be treated differently:

  • staff under 18 are not usually allowed to work at night - there are also other restrictions on when they can work
  • night workers who deal with special hazards or whose work involves mental or physical strain can’t work longer than 8 hours in any 24-hour period

Special hazards and work involving mental or physical strain should be identified as part of risk assessments. They may also be set out in collective or workforce agreements.

Exceptions to night hours limits

There are some jobs and situations when night work limits don’t apply.

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