Almost every week I'm contacted by police officers, sheriff's deputies, and patrolmen about 10-hour shifts. They believe that 10-hour shifts would benefit themselves and their fellow officers. I believe there are two reasons they think 10s would be an improvement over their current 8-hour schedule. I will take a closer look at each of these in an attempt to sort out the reality from the myth.
  

Time Off 

In 24/7 operations, typical schedules using 8, 10 or 12-hour shifts provide the following number of days and weekends off:
  

Shift Length        Days Off Per Year             Max. Weekends Off

   8-hour                           91                                       25%

 10-hour                          146                                      40%       

 12-hour                          182                                      50%

It is clear that 10-hour shifts offer more days off and more weekends off than 8s, but not as many as 12s. I believe that 10s are the most popular shift length because they offer more time off than 8s and they are seen as more tolerable than 12s. If the only objective was to maximize time off, 12-hour shifts would be the clear winner.

The key point that is often overlooked is absence coverage. With 8-hour shifts, absences are covered either by holding someone over from the previous shift or by splitting the vacant shift into two 4-hour components that can be covered by the preceding and following shifts. With 10-hour and 12-hour shifts, absences must be covered by calling someone in from a scheduled day off. Many law enforcement agenices have built additional coverage into their schedules to compensate for their high absence rates. But what happens if that extra coverage isn't available? Since 10-hour shifts will reduce the available coverage by at least 25%, there won't be any extra capacity to cover absences. So, instead of getting the expected 3 days off every week, the officers might only get 1 or 2 days off.

On/Off Work Patterns

The common perception of 10-hour work patterns is 4 days of work followed by 3 days off. In 24/7 operations, however, this pattern only works if you use 6 crews and fixed days of work. This requires a lot more staff, a backwards rotation, and fixed days of work. You can read more about this approach and its shortcomings here:  http://www.shift-schedule-design.com/Blog?m8:post=problems-with-free-schedule-examples 

The best 10-hour schedule for 24/7 operations uses 7 crews per shift or 21 total crews. There is no built-in overtime with this schedule. It also has the most attractive work pattern (4 or 5 consecutive days of work followed by 3 or 4-day breaks). The pattern can easily be adapted for use with either fixed or rotating shifts.

If you don't have 7 officers or a multiple of 7 (14, 21, 28, etc.) per shift, your 10-hour schedule will have shorter blocks of work (two to four days) and shorter breaks (one to three days). Many officers are disappointed when they see these patterns because there are so many one and two-day breaks. These patterns are especially unattractive to anyone who is expecting to consistently get 3 consecutive days off by changing to 10-hour shifts.

Organization and Supervision 

Many 8-hour and 12-hour schedules use 4 squads. Squad members work the same shift(s) and the same days of the week. 10-hour shift schedules for small organizations (less than 50 people), rarely use squads. Some days, Officer A might be working with officers C and E. On other days, he or she might be working with officers B and D, or maybe with officers G and J.

With 8 or 12-hour shift schedules, each squad usually has a sergeant or corporal who acts as the team leader/supervisor. With 10-hour shifts, in order to ensure that a supervisor is always on duty, it's necessary to put them on their own, separate schedule. This means the officers will not always be working with the same supervisor after changing to a 10-hour shift schedule.  

Conclusions 

10-hour shifts provide more time off than 8-hour shifts, but not as much as 12-hour shifts. The extra days off may not be realized since some of them will probably be used to cover absences. Although the schedule will provide 3 days off for most weeks, they won't always occur on consecutive days. 10-hour shifts also will change the way the group is organized and supervised. Although 10-hour shifts are clearly more attractive than 8-hour shifts, they may not live up to the high expectations that many police officers have of them. I think the shift length debate among officers should not be 8s vs. 10s, but 10s vs. 12s.

Please check out my other 10-hour blog posts, especially 10-hour shifts and Police Management. Go to the search box and type in 10 hour shifts. You really need to educate yourself about this before making a choice you might regret.