The U.S. Navy has adopted another more efficient personnel practice from the civilian world. This one has to do with how the sailors work schedule at sea is organized. For a long time most crew worked five hours then had ten hour off. That 15 hour day was out of sync with the 24 hour day and sailors at sea were constantly changing their work schedule despite the damage that does to an individual’s circadian rhythm. Commercial firms have found that workers who change shifts a lot suffer from reduced alertness, productivity and morale. That’s all because the circadian rhythm (sleep on a regular schedule in order to be most alert and healthy) cannot be fooled. The circadian rhythm is most efficient when people sleep at night, but you can work night regularly with some decrease in effectiveness if you stick with the night shift for a long time. The greatest losses in alertness and efficiency come when you constantly change the time you can sleep. Thus the navy’s traditional work schedule was the most inefficient available.
The navy has tested a new schedule what respects the circadian rhythm and has found (via sensors sailors wore during testing) that alertness was much improved and opinion surveys found morale was much higher as well. The navy made the switch by adopting a three hours of work and nine hours off schedule. Both this and the older 5 and 10 schedule also included interruptions for drills and emergencies. But the new schedule is much appreciated because it doesn’t fight the circadian rhythm and the sailors quickly felt the beneficial impact of that.