Sometimes an organization's scheduling requirements make it difficult to find a solution. Here an example from last week. This client operated on a 24/7 basis. It used to have 7 employees, but was just given authorization to hire an 8th person. They wanted 8-hour rotating shifts with no overtime in the schedule. The difficulty was the labor agreement that required employees to have 3 days off after any series of night shifts.

My first step was to determine what kind of coverage the 8 employees could produce without incurring any overtime. We discussed a couple of different possibilities and the client agreed on weekday coverage of 3 on days, 2 on afternoons, and 1 on nights. The weekend coverage would be 2 on days, 2 on afternoons and 1 on nights. This combination of variable coverage (shift-to-shift and weekday-to-weekend), no overtime, and 3 days off after the night shifts made the schedule design especially challenging.

My second step was to create a schedule primarily using 7 consecutive shifts. This is shown below:

The way this schedule works is that the 8 employees are initially assigned to different weeks of the schedule (A to Week 1, B to Week 2, and so on). After they complete the first week, they move down to the next week of the schedule. They continue doing this until they finish the 8th week of the schedule, after which they rotate up to Week 1. All 8 employees are working the same schedule; they are simply in different weeks of the 8-week cycle.

Although this achieved the desired coverage and had 4 days off after the night shifts ended in Week 4, there was one 48-hour work week and one 32-hour work week. My first thought was to simply move a shift from Week 2 to Week 8 to balance the hours. The only open days in Week 8 were Thu, Fri and Sat. Moving the Thu shift from Week 2 would leave an isolated workday (Wed) in that week. Moving the Fri or Sat shift would result in an isolated workday in Week 8. An isolated workday is one with days off both before and after it, which makes it vulnerable to excessive absences.

Obviously, my initial approach would not satisfy all of the requirements. There are no rules of thumb or proven procedures for doing what I did next. It's like trying to solve a puzzle by moving shifts around and experimenting with different approaches. Finally, I was able to come up with 5 options that worked. Here is one of them - just to show you that it can be done:

If you have multiple requirements like this client did, designing it by yourself will probably be too time-consuming or too frustrating. You might be tempted to accept inconsistent coverage or coverage that doesn't match your desired levels. But is it really worth those kinds of sacrifices, when you can hire a reasonably-priced expert to help?