The ''Zheng He'', like all long-duration ASWF ships, uses a circadian watch system in which, under normal conditions, each crewmember has consistent sleeping hours (though the activities during his or her waking hours, in particular watchstanding, may take place at varying times of day.) The day is divided into four six-hour watches. The crew is divided into five watch sections, designated by a letter A-E. In any given day, four of the five watch sections will stand watches and one is enjoying an extended rest period, albeit one possibly interrupted by occasional events like meetings. 

Despite being generous in comparison to analogous 20th-century systems of continuous manning, it is considered rigorous by contemporaries in the Twelve Worlds, many of whom are accustomed to the equivalent of a 20-30-hour workweek (12-18% time working), largely the effect of greater automation in their societies in comparison to 20th century earth. The personnel in this watch system are working about 30% of the time depending on mission needs. (For comparison, a 40-hour workweek is 24% work-time.)

||||||||||||||||||||||||''AWSF Circadian Watch System''||
||'''Watch'''||||||||||||||||||||||'''Watch Section''||
||         ||Day 1||Day 2||Day 3||Day 4||Day 5||Day 6||Day 7||Day 8||Day 9||Day 10||
||0000-0559||A||B||A||B||A||B||A||B||A||B||
||0600-1159||B||E||B||A||E||A||B||E||E||A||
||1200-1759||C||D||E||E||C||D||E||D||C||E||
||1800-2359||D||C||D||C||D||C||D||C||D||C||
||No watch ||'''E'''||'''A'''||'''C'''||'''D'''||'''B'''||'''E'''||'''C'''||'''A'''||'''B'''||'''D'''||

It can be observed that sections A-D alternate 3 on - 1 off - 5 on - 1 off, whereas section E always has 4 on - 1 off.
Watch sections A-B and have their protected rest period in the evening, C-D have it in the morning.

||||''Protected Rest Periods''||
||Watch Section||Rest Period||
||A||1230-1930||
||B||1630-2330||
||C||0030-0730||
||D||0330-1130||
||E||1830-0230 or 2230-0530 (split)||

Rest periods are structured to maximize the chances that it will be possible to satisfy irregular personnel needs with crewmembers who are already awake (albeit off-duty) rather than by waking someone.
Crewmembers in protected rest periods are ordinarily excused from non-emergency duties, e.g. serving as drill monitors or attending meetings. This is only the case for their protected rest period, though, not their days off.