Different Watch Structures

Traditional System

Middle Watch 0000-0400
Morning Watch 0400-0800
Forenoon Watch 0800-1200
Afternoon Watch 1200-1600
First Dog Watch 1600-1800
Second Dog Watch 1800-2000
First Watch 2000-0000

Watch standers were organized into two watches, the port watch and the starboard watch, and they would take alternating turns manning the ship for the aforementioned hours. The purpose of the dog watches was to allow each sailor to stand a different watch the following day, ensuring a fair distribution of time spent awake (nobody is left with the graveyard shift for the duration of the voyage).

Two vs. Three Watches

Originally every person had an equal amount of time on as off, this is known as the “watch on watch off” or two watch system. As each watch lasted at most four hours this means that no person was able to sleep longer than four hours in a given period. On modern vessels adhering to international maritime conventions the amount of rest due to each seafarer is closely regulated. Because of this the three watch system is used. This breaks up the ship’s company into three equal parts instead of two parts. Each of the three watches therefore stand one watch and take the following two watches off for personal time. If four hour watches are implemented, for example, this means a watch stander would work for four hours and take eight hours off.

Six Hour Watch System

Mid Watch 0000-0600
Morning Watch 0600-1200
Afternoon Watch 1200-1800
Evening Watch 1800-0000

Using three watches this system allows six hours on, twelve hours off, enabling an additional amount of time for self-maintenance such as showering, laundry, and recreation while still allowing time for an unbroken eight hour rest period. This still rotates the time spent awake during the day, with three watches, without requiring the watches to be dogged (e.g., no dog watches).

Other Watch Systems

Work boats often employ a 12 Hour System, swapping out either at noon and midnight or 0600 and 1800, with only two watches. These do not rotate, the senior watch leader taking the days and the junior watch leader taking nights. This enables the Captain or Chief Engineer, who work days, for example, to make phone calls and have access to regular business hours for communications to the office or shoreside vendors. There are also some 16 On/8 Off Systems typically found on fish processing boats where vessel production is valued higher than personal comfort.

There is also a Swedish System which has watches of various lengths throughout the day, and many others besides. The important thing to remember is that long watches may allow long periods of rest but it also demands increased periods of endurance for the amount of time they must remain vigilant and alert. Many systems have been created and implemented throughout the years.