The broad principle behind the Working Time Regulations 1998 is that workers should not be required to work more than 48 hours on average in a week unless they have agreed in writing to do so. The Regulations specify how the average must be calculated and lay down the conditions that must be met if a worker is validly to 'opt out' of the weekly limit (see 'Opting out' below). For young workers under 18, there is an absolute limit of 40 hours on the working week and eight hours on the working day, with no possibility of averaging or 'opting out' (employee characteristics ).
Employers must take 'all reasonable steps' to ensure that these limits are met. The BERR guidance assumes that the limits apply to work from whatever source, and suggests that employers may wish to ask their workers if they have other jobs. If an employer knows that a worker has another job that may take him or her over the 48-hour limit, the employer can then agree an opt-out with the worker. On the other hand, if a worker is taken over the limit because he or she has another job that the employer does not know about and could not reasonably have discovered, it is extremely unlikely that the employer would be found to have breached the Regulations.
The first step in calculating whether a worker has exceeded the 48-hour limit is to identify the reference period over which the average has to be calculated.
The starting point is that the reference period is 17 weeks. This is a rolling period of any 17 weeks in the course of the worker's employment, unless a relevant agreement specifies successive fixed periods of 17 weeks (such as, for example, each successive 17-week period beginning on 1 January 2007).
For new recruits who have not yet worked for 17 weeks, the reference period is the period for which they have been employed. The reference period can be increased to up to 52 weeks by a collective or workforce agreement, if there are objective or technical reasons or reasons concerning the organisation of work that justify doing so. For the workers referred to as 'other special cases', (other special cases ) the reference period is 26 weeks.
Certain days in the reference period are called 'excluded days'. These are days when the worker is taking annual holiday entitlement under the Regulations or is on sick leave or maternity, paternity, adoption or parental leave, and any days covered by the worker's agreement to 'opt out' of the 48-hour week (see 'Opting out' below).
In order to calculate the average:
- Take the number of hours the worker has worked during the reference period.
- Add the number of hours the worker has worked in the first X days after the reference period when the worker has worked, where X is the number of 'excluded days' in the reference period.
- Divide the result by the number of weeks in the reference period.
A worker can opt out of the 48-hour limit by agreeing in writing, in advance, to work longer hours. An opt-out agreement can relate to a specified period, or apply indefinitely. It can include a term requiring the worker to give up to three months' notice to terminate the agreement. If there is no notice clause in the agreement, the worker need only give seven days' notice in writing to terminate an opt-out ( Opt-Out Agreement ).
For workers under 18, there is an absolute limit of 40 hours on the working week and eight hours on the working day, with no possibility of averaging or 'opting out'. These limits can be exceeded if the young worker is needed to maintain continuity of service or production or to respond to a surge in demand, provided no adult is available to do the work and the work would not adversely affect the young worker's education or training. It is also lawful to exceed the limits if the young worker is needed to work immediately because of unusual and unforeseeable circumstances or exceptional events, provided the work is only temporary and no adult is available to do it. The young worker must be given an equivalent period of compensatory rest within the following three weeks.