The shift plan, also known as a rota or roster (esp. British), is the central component of a shift schedule in shift work. The schedule includes considerations of shift overlap, shift change times and alignment with the clock, vacation, training, shift differentials, holidays, etc. The shift plan determines the sequence of work (W) and free (F) days within a shift system.
Notation
A notation used often identifies day (D), swing (S) and night (N) shifts for the W days and O (off) for rest days.
W work days D day shift, 1st shift, early shift This shift often occurs from either 06:00 or 07:00 to either 14:00 or 15:00 for eight-hour shifts, and from 06:00 to 18:00 for twelve-hour shifts. S swing shift, 2nd shift, late shift, back shift, afternoon shift This shift often occurs from either 14:00 or 15:00 to either 22:00 or 23:00 for eight-hour shifts, and is not used with twelve-hour shifts. N night shift, 3rd shift, graveyard shift This shift often occurs from either 22:00 or 23:00 to either 06:00 or 07:00 for eight-hour shifts, and from 18:00 to 06:00 for twelve-hour shifts. F free days O days off This is defined as a day on which a shift does not begin.
A~F work teams (starts from A as first team)
Note that a worker transitioning from N to O works for the first six or seven hours of the first day "off". Thus, when days off follow night shifts, the first one or more days "off" are, in fact, days of recovery from lack of nighttime sleep. This daily notation refers to the start of a shift. If a shift starts at 23:00, then this is a W day even though only one hour is worked. The day after this shift is an F day if no shift starts on this day, though many hours have been worked from midnight on.
One shift system may allow many shift plans. For example, the twelve-hour, 2nW:2nF system with n = 1 allows twelve different plans in three serially-identical sets. Within a set, DONO has the same sequence as NODO. DNOO is the preferred sequence because days off follow night work and there are two consecutive days off.
Shift plans may also be expressed by assigning shifts and days off to calendar dates. In this form, a repeating sequence such as DDNNOOOO is applied to successive dates, with each symbol indicating the corresponding shift or day off.
Three-day shift plans
Prior to 2014, the U.S. Navy used a three shift system with an 18-hour day instead of a 24-hour day. The 24-hour period was divided into four shifts: 00:00-06:00, 06:00-12:00, 12:00-18:00, and 18:00-00:00. A sailor stood watch on their shift. During the off shift there is time to perform maintenance, study for qualifications, and handle collateral duties. During off time the sailor has time to sleep, relax, and perform personal tasks, such as laundry. With sufficient personnel, a given watchstation may benefit from a fourth man (the midnight cowboy or "Balls-to-6"). He would stand the same 6-hour watch in a given 24-hour period, usually from midnight to 06:00 (hence the midnight portion of the name, often shortened to cowboy) and the normal watchstander would then be free. This gave rise to a schedule of six on, twelve off, six on, thirty off, six on, twelve off.
Beginning in 2014, the Submarine Force began shifting to a 24-hour day, with watches split into 8 hours on, 16 hours off. This does have the side effect of sailors assigned to a certain shift having the same meals every day, and so the shifts are periodically rotated in order to provide variety.
The Surface Fleet began its shift in 2017, transitioning from their "five and dimes" approach of 5 hours on, 10 hours off.
This does not apply to the attached air wing, which will work a 12 on, 12 off schedule 7 days a week.
+Navy three-shift example Time Mon Tue Wed Thu Fri Sat Sun on watch off AW on watch off AW on watch off AW on watch off AW on watch off AW on watch off AW on watch off AW 06:00–12:00DDDDDDD 12:00–18:00EEEEEEE 18:00–06:00EEEEEEE Plan Run 1 Run 2 Run 3
4-day shift plans
In the 12/24/12/48 or 12/24 plan, employees work in shifts of 12 hours; first a "daily shift" (e.g. 07:00 to 18:00), followed by 24 hours' rest, This plan needs four teams for full coverage, and makes an average 42-hour workweek. The pattern repeats in a 4-week cycle, i.e. over 28 days, and has 14 shifts per employee therein.
+12/24/12/48 shift example Time Week 1 Week 2 Week 3 Week 4 Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Daily 06:00–18:00 Nightly 18:00–06:00 Plan Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7
Five-day shift plans
In four on, one off the employee only gets one day off after a work streak of four days. There are 28 shifts per employee in a five-week cycle (i.e. 35 days). This adds up to an average of 42 hours worked per week with 7½-hour shifts. This plan is mainly adopted by industries in which companies prefers to work for all days of the week, often with four (overlapping) shifts per day, and where laws do not let employees work for 12 hours a day for several days. Five groups of employees are needed to cover a specific shift on all days, where each group gets a different day off.
+ two on, one off example with 8-hour shift Time Week 1 Week 2 Week 3 Week 4 Week 5 Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun 08:00–15:30 A A A A A A A A A A A A A A A A A A A A A A A A A A A A B B B B B B B B B B B B B B B B B B B B B B B B B B B B C C C C C C C C C C C C C C C C C C C C C C C C C C C C D D D D D D D D D D D D D D D D D D D D D D D D D D D D E E E E E E E E E E E E E E E E E E E E E E E E E E E E Plan Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7
Six-day shift plans
In four on, two off the employee gets two days off. There are 28 shifts per employee in a six-week cycle (i.e. 42 days), this adds up to an average of 56 hours worked per week with 12-hour shifts, or hours per week with 8-hour shifts. Three groups are needed for each time span, i.e. to cover the whole day and week a company needs 6 groups for 12-hour shifts or 9 groups for 8-hour shifts. This plan is mainly adopted by industries in which employees do not engage in much physical activity.
+Four on, two off example with one 8-hour shift per day Shift Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun 07:00–19:00 Plan Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7
Week shift plans
Three-shifts
The three-shift system is the most common plan for five 24-hour days per week. The "first shift" often runs from 06:00 to 14:00, "second shift" or "swing shift" from 14:00 to 22:00 and a "third shift" or "night shift" from 22:00 to 06:00, but shifts may also have different length to accommodate for workload, e.g. 7, 8 and 9 or 6, 8 and 10 hours. To provide coverage 24/7, employees have their days off ("weekends") on different days.
All of the shifts have desirable and less desirable qualities. First shift has very early starts, so time in the evening before is heavily cut short. The second shift occupies the times during which many people finish work and socialize. The third shift creates a situation in which the employee must sleep during the day; it may be preferred for night owls, for whom this is a desired sleep pattern.
+Three-shift example Time Mon Tue Wed Thu Fri Sat Sun 07:30–14:30 14:30–22:30 22:30–07:30
To provide an overlap in shifts, some employers may require one of the shifts to work four 10-hour shifts per week (as opposed to five 8-hour shifts, both are 40 hours per week). In that scenario, the night shift might extend from 21:00 to 07:00, but the night- shift would have nearly four days off (86 hours) between work weeks. This change, along with first shift moving a half-hour later, or second moving a half-hour earlier, ensures at least a half-hour overlap between shifts, which might be desirable if the business is open to the public to ensure that customers continue to be served during a shift change.
Some U.S. states, such as California, accommodate this arrangement by allowing the employee to be paid at their regular rate (as opposed to time-and-a-half, or an overtime rate, that would normally be required for any time past 8 hours) for the 10-hour shift, calling this an "alternative workweek".
Four on, three off
In four on, three off, each employee works four days and gets a three-day weekend. For some types of manufacturing, this is a win-win arrangement. For example, a paint company had been making 3 batches of paint per day, Sunday through Saturday (3 × 5 = 15). They changed to making 4 batches of paint, Monday through Thursday (4 × 4 = 16). Total worker hours remained the same, but profits increased. In exchange for two additional hours of work per day, over 4 days, workers got an additional day off every week. See also the book, 4 Days, 40 Hours. + Four on, three off example with 10-hour shifts (in comparison to five-day week schemes) Time Mon Tue Wed Thu Fri Sat Sun 4-day week 08:00–18:00 4½-day week 08:00–17:00title="08:00–12:00" 5-day week 09:00–17:00
Continental plan
Continental plan, adopted primarily in central Europe, is a rapidly changing three-shift system that is usually worked for seven days straight, after which employees are given time off, e.g. 3 mornings, 2 afternoons and then 2 nights.
+Continental shift example Time Mon Tue Wed Thu Fri Sat Sun 06:00–14:00 14:00–22:00 22:00–06:00
24*7 shifts
In the 24*7 plan there are 24 consecutive shifts of 7 hours per week, hence covering 24/7. With 4 groups and 6 shifts per group, the work time is 42 hours per week. Several sub-patterns are possible, but usually each group is responsible for one of four time slots per day. Each of these is 6 hours long and if a shift begins in their time slot, a group has to work it. This way there are 14, 21 or 42 hours of rest between shifts, every group gets one whole day off. Shifts can be swapped to make double-shifts and increase the minimum time of rest.
+ 24*7 example with double shifts and long rests around them Shift/Group Work time window Mon Tue Wed Thu Fri Sat SunNight 21:00–09:00 21:00–04:00 01:00–08:00 22:00–05:00 00:00–07:00 Morning 03:00–15:00 04:00–11:00 08:00–15:00 05:00–12:00 02:00–09:00 Day 06:00–18:00 15:00–22:00 12:00–19:00 09:00–16:00 13:00–20:00 Evening 15:00–03:00 19:00–02:00 16:00–23:00 20:00–03:00 17:00–24:00
Split shift
Split shift is used primarily in the catering, transport, hotel, and hospitality industry. Waiters and chefs work for four hours in the morning (to prepare and serve Lunch), then four hours in the evening (for an Evening meal). The average working day of a chef on split shifts could be 10:00 to 14:00 and then 17:00 to 21:00
+Split shift example Shift Time Mon Tue Wed Thu Fri Sat Sun Lunch 10:00–14:00 Break 14:00–17:00 Dinner 17:00–21:00
Earlies and lates
Earlies and lates is used primarily in industries such as customer service (help desk, phone-support), convenience stores, child care (day nurseries), and other businesses that require coverage greater than the average 09:00 to 17:00 working day in the UK, but no 24/7 coverage either. Employees work in two shifts that largely overlap, such as early shift from 08:00 to 16:00 and late shift from 10:00 to 18:00
+Earlies and lates shift example Shift Time Mon Tue Wed Thu Fri Sat Sun Morning Evening
In businesses where two shifts are necessary to cover the day, earlies and lates may be combined with one double shift per week per worker. Six 7-hour shifts in five days and seven 6-hour shifts in six days both result in 42 hours per week.
+ Earlies and lates with double shift example, six 7-hour shifts in five days, ten groups Shift Time Mon Tue Wed Thu Fri Sat Sun Earlies 08:00–15:00 Lates 15:00–22:00