Chapter VIII - Watchkeeping: Fitness for Duty and Watch Arrangements
Fitness for duty (VIII/1)
The baseline is rest, not work:
- at least 10 hours of rest in any 24-hour period;
- at least 77 hours of rest in any 7-day period;
- rest may be divided into no more than two periods, one of which is at least 6 hours long;
- the interval between consecutive rest periods must not exceed 14 hours;
- watch schedules must be posted, and hours of work and rest recorded and signed.
Under the ILO Maritime Labour Convention the same idea is expressed as work limits: maximum 14 hours worked in 24 and 72 in 7, with a minimum of 6 hours between watches. Where both apply, the more protective rule wins. A frequent distractor offers "10 hours work" or "77 hours work" - those numbers belong to rest.
Watchkeeping arrangements (VIII/2)
The master is responsible for safe watchkeeping; the bridge must never be left unattended and a look-out must be maintained. A sole look-out may be kept only in daylight, in good visibility, after a risk assessment and a documented decision by the master, and only while the OOW can give full attention to the watch - with an extra look-out called the moment anything changes.
Worked example
A watchkeeper logs 10 hours of rest in 24, split into 5 hours after the morning watch and 5 hours before the next. The total is correct, but the rule requires one uninterrupted block of at least 6 hours, so the arrangement is non-compliant; adding an hour to one block fixes it.
Rule of thumb: check the shape of the rest, not only the total - total hours, number of blocks, and the longest block.