The crew of the USS Sutherland is organised into four shifts, each serving for 8 hours, with one shift per 24 hour day rostered off. This means that no person needs to serve more than three days in a row and that there is 24 hours between each active shift. It also means that in times of emergency, such as illness, a crewman may pull a double shift in the place of a missing colleague.
The Passive service period is distributed freely amongst the 24 hours of non-Active service. It is rostered so there is always one person in any given position manning Smoko bay .