The crew of the USS Explorer is not organised into the normal four shifts. Instead of individuals serving for 8 hours, with one shift per 24 hour day rostered off, each indivdual is expected to manage their time so that they are on call for emergencies. Since so many of the Explorer systems are automated crewmen are almost redundant in the normal running of ships business. It does means that in times of emergency, such as illness, a crewman may need to pull a shift in a secondary position in place of the missing colleague. All Explorrer crew are picked for their adaptability and multiskilling performance.
The Passive service period is normally 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. On the USS Explorer all crew are considered to be on Passive duty full time.