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Industrial & Organisational : Introduction : Personnel : Organizational psychology : Occupations: Work environment: Index : Outline


There are a variety of workday shift patterns:

Shift patternsEdit

Panama ScheduleEdit

The Panama schedule follows a 3-2-2-3 pattern in which shift workers generally are allowed every other Friday, Saturday, and Sunday off, with two additional days off during the week, although this may differ depending on organization and industry. The most common form utilizes four shifts, each working twelve hours, with two shifts generally paired together (A working days and B working nights while C and D are off, and vice versa). It is not uncommon for shifts to rotate between days and nights, most often with six months spent on nights and six on days. This shift is sometimes known as 2-2-3, or "two, two, and three".

Time Sun Mon Tues Wed Thur Fri Sat Sun Mon Tues Wed Thurs Fri Sat
06:00 to 18:00 Off On On Off Off On On On Off Off On On Off Off

6 on 6 offEdit

Consists of 3 days and 3 nights.Then 6 days off. These will alternate between other crews A.K.A teams for a full 24/7 operation.

Three-shift systemEdit

The "three-shift system" is the most common pattern, with "first" from 06:00 to 14:00, "second" from 14:00 to 22:00, and a "third" (or "night") shift from 22:00 to 06:00 This is generally worked over a five-day week; to provide coverage 24/7, employees have their days off ("weekends") on different days.

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.[1]

Some 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." [1]

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 (or "swing 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.

Generally, employees stay with the same shift for a period of time, as opposed to cycling through them; this is seen as healthier.[citation needed]

Three-shift example:

Time Sat Sun Mon Tues Wed Thur Fri
06:00–14:00 Shift 1 Shift 1 Shift 1 Shift 1 Shift 1 Off Off
14:00–22:00 Shift 2 Shift 2 Shift 2 Shift 2 Shift 2 Off Off
22:00–06:00 Shift 3 Shift 3 Shift 3 Shift 3 Shift 3 Off Off

Four on, four offEdit

Four on, four off is a shift pattern that is being heavily adopted in the United Kingdom and in some parts of the United States.[citation needed] An employee works for four days, usually in 12-hour shifts (7:00 to 7:00) then has four days off. While this creates a "48-hour week"(42-hour average over the year) with long shifts, it may be preferred because it shrinks the work week down to four days, and then gives the employee four days rest—double the time of a usual weekend. Due to the pattern, employees effectively work an eight-day week, and the days they work vary by "week". As with three-shift system, most employees stay with the same shift rather than cycling through them.

Four on, four off example:

Time 7:00-7:00 Sat Sun Mon Tues Wed Thur Fri Sat
07:00–19:00 Day 1 Day 2 Day 3 Day 4 Off Off Off Off

Such shifts are popular within the Australian ambulance and fire sector. However it is often referred to as a "ten-fourteen" roster, as the day shift lasts for ten hours, with the night shift lasting fourteen. Extended night shift such as these are often a double edged sword; on one hand crews on slower weeknight shifts, or those in areas of low demand will receive excellent levels of rest (when there are no calls for emergency services, crews are encouraged to rest if required). Conversely, those employed on high demand days such as weekend nights, or in particularly high demand areas, will often be required to be awake or working for their entire rostered shift. However due to the scheduled nature, most ambulance and fire employees can attempt to obtain sufficient rest before or after a particularly busy 14-hour night shift.

Navy Three-shift underway systemEdit

The US Navy uses a three shift system that relies on an 18 hour day instead of a 24 hour day. The 24 hour period is broken up into 4 shifts. 00-06, 06-12, 12-18, and 18-00. A sailor will stand watch on his shift. During his offgoing shift he will have time to perform maintenance, work on qualifications and handle all his collateral duties. During the oncoming time the sailor has time to sleep, relax, and do whatever personal things he needs to do like laundry. 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: Shift 1

Time Sat Sun Mon Tues Wed Thur Fri
00:00–06:00 Shift 1 Offgoing Oncoming Shift 1 Offgoing Oncoming Shift 1
06:00–12:00 Offgoing Oncoming Shift 1 Offgoing Oncoming Shift 1 Offgoing
12:00–18:00 Oncoming Shift 1 Offgoing Oncoming Shift 1 Offgoing Oncoming
18:00–00:00 Shift 1 Offgoing Oncoming Shift 1 Offgoing Oncoming Shift 1

Navy Three-shift example: Shift 2

Time Sat Sun Mon Tues Wed Thur Fri
00:00–06:00 Oncoming Shift 2 Offgoing Oncoming Shift 2 Offgoing Oncoming
06:00–12:00 Shift 2 Offgoing Oncoming Shift 2 Offgoing Oncoming Shift 2
12:00–18:00 Offgoing Oncoming Shift 2 Offgoing Oncoming Shift 2 Offgoing
18:00–00:00 Oncoming Shift 2 Offgoing Oncoming Shift 2 Offgoing Oncoming

Navy Three-shift example: Shift 3

Time Sat Sun Mon Tues Wed Thur Fri
00:00–06:00 Offgoing Oncoming Shift 3 Offgoing Oncoming Shift 3 Offgoing
06:00–12:00 Oncoming Shift 3 Offgoing Oncoming Shift 3 Offgoing Oncoming
12:00–18:00 Shift 3 Offgoing Oncoming Shift 3 Offgoing Oncoming 'Shift 3
18:00–00:00 Offgoing oncoming Shift 3 Offgoing Oncoming Shift 3 Offgoing

Four on, three offEdit

Main article: Four-day week

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, Monday through Friday (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, two offEdit

In four on, two off the employee only gets two days off. In a seven-day period, this adds up to 60 hours worked (on average, based on 12-hour shifts). Four on, two off is mainly adopted by industries in which employees do not engage in much physical activity.

Four on, two off example:

Time Sat Sun Mon Tues Wed Thur Fri
07:00 to 19:00 Day 1 Day 2 Day 3 Day 4 Off Off Day 5

Four on, one offEdit

In four on, one off the employee only gets one day off. In a seven-day period, this adds up to 48 hours worked (on average, based on 8-hour shifts). Four on, one off is mainly adopted by industries in which companies prefers to work for all days of the week with four shifts and where laws do not let employees work for 12 hours a day for several days.

Four on, one off example:

Time Sat Sun Mon Tues Wed Thur Fri
07:00–15:00 Day 1 Day 2 Day 3 Day 4 Off Day 5 Day 6

Two days, two nights, four offEdit

A variation is the two days, two nights, four off pattern of working. In this shift schedule, employees work 12-hour shifts from 06:00 to 18:00 on day shifts and from 18:00 to 06:00 on nights. This pattern is currently in use by HM Coastguard in the UK, and employs four separate teams to maintain 24/7 coverage.

Two days, two nights, four off example:

Time Sat Sun Mon Tues Wed Thur Fri Sat
06:00–18:00 Day 1 Day 2 Off Off Off Off Off Off
18:00–06:00 Off Off Day 3 Day 4 Off Off Off Off

5/4/9sEdit

"5/4/9s" (or "Five/Four Nines", or "9/80") is another variation. Employees work in 2 week cycles. Week 1 the employee works 4 days of 9 hours followed by 1 day of 8 hours with 2 days off (week 1: 44 hours). Week 2 the employee works 4 days of 9 hours with 3 days off (week 2: 36 hours). This pattern works to 80-hours in a 2 week pay-period (comparable to working 8 hours a day for 5 days a week). The benefit to working an extra hour a day gives you a "normal" 2 day weekend followed by a long 3 day weekend the next. Typical working hours for this type of shift would be 06:00 to 15:30 (9 hours with 30 minutes lunch) and 06:00 to 14:30 (8 hours with 30 minutes lunch) on the 8-hour work day. Often the employer will alter the starting times (e.g., start at 07:00 or 08:00). Also referred to as "9/80" as employees have nine days to work 80 hours.

5/4/9s shift example:

Week Mon Tues Wed Thur Fri Sat Sun
Week 1 9 hrs 9 hrs 9 hrs 9 hrs 8 hrs Off Off
Week 2 9 hrs 9 hrs 9 hrs 9 hrs Off Off Off

12/24/12/48Edit

12/24/12/48 (or 12/24) is another variation. Employees work in shifts of 12 hours; first a daily shift (e.g., 07:00 to 19:00), followed by 24 hours rest, then a nightly shift (19:00 to 07:00), finishing with 48 hours rest. This pattern needs four teams for full coverage, and makes an average 42-hour workweek.

12/24/12/48 shift example:

Time Sat Sun Mon Tues Wed Thur Fri
06:00–18:00 Day 1 Off Off Off Day 3 Off Off
18:00 to 06:00 Off Day 2 Off Off Off Day 4 Off

Continental shiftEdit

Continental shift, 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. For example, three mornings, two afternoons, and then two nights.

Continental shift example:

Time Sat Sun Mon Tues Wed Thur Fri
06:00–14:00 Shift 1 Shift 1 Shift 1 Off Off Off Off
14:00 to 22:00 Off Off Off Shift 1 Shift 1 Off Off
22:00–06:00 Off Off Off Off Off Shift 1 Shift 1

Split shiftEdit

Main article: 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 serve lunch), then four hours in the evening (to serve 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:

Time Sat Sun Mon Tues Wed Thur Fri
10:00–14:00 On On On On On Off Off
14:00–17:00 Off Off Off Off Off Off Off
17:00–21:00 On On On On On Off Off

Earlies and latesEdit

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 9:00 to 5:00 working day in the UK. 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:

Time Sat Sun Mon Tues Wed Thur Fri
08:00–16:00 Shift 1 Shift 1 Shift 1 Shift 1 Shift 1 Off Off
15:00–23:00 Shift 2 Shift 2 Shift 2 Shift 2 Shift 2 Off Off

7-day fortnight shiftEdit

In the 7-day fortnight shift pattern, employees work their allotted hours within 7 days rather than 10. Therefore, 41 hours per week equate to 82 hours per fortnight (fourteen days and nights), which is worked in seven days, at 11–12 hours per shift. This shift structure is used in the broadcast television industry, as well as many law enforcement agencies, as well as health care fields such as nursing and clinical laboratories in the US.

7-day fortnight shift example:

Week 1
Time Wed Thur Fri Sat Sun Mon Tue
Days
08:00 to 20:00
Shift 'A'
Day 1
Shift 'A'
Day 2
Shift 'C'
Day 1
Shift 'C'
Day 2
Shift 'C'
Day 3
Shift 'A'
Day 3
Shift 'A'
Day 4
Nights
20:00 to 08:00
Shift 'B'
Night 1
Shift 'B'
Night 2
Shift 'D'
Night 1
Shift 'D'
Night 2
Shift 'D'
Night 3
Shift 'B'
Night 3
Shift 'B'
Night 4
Week 2
Time Wed Thu Fri Sat Sun Mon Tue
Days
08:00 to 20:00
Shift 'C'
Day 4
Shift 'C'
Day 5
Shift 'A'
Day 5
Shift 'A'
Day 6
Shift 'A'
Day 7
Shift 'C'
Day 6
Shift 'C'
Day 7
Nights
20:00 to 08:00
Shift 'D'
Night 4
Shift 'D'
Night 5
Shift 'B'
Night 5
Shift 'B'
Night 6
Shift 'B'
Night 7
Shift 'D'
Night 6
Shift 'D'
Night 7

One of the advantages of using this pattern is each shift pair, for example A and B, will get time off on weekends alternatively, because the schedule is fixed and does not drift.

DuPont 12-Hour rotating shiftEdit

The DuPont 12-Hour rotating shift provides 24/7 coverage using 4 crews and 12-hour shifts while providing a week off. Average hours is 42 per week but contains a 72-hour week which can be challenging. It is used in several manufacturing industries in the US. Companies that have gone to this schedule have noticed a decrease in accidents plus more rest for employees, less call ins, and more coverage when crews are short handed. In all the schedule is designed to improve safety. A particular advantage of this pattern is that it can readily be slewed to fit business requirements. For example if less coverage is required on a Sunday, stand-alone shifts are avoided by scheduling the fourth night and first day of four on that day. This also has the additional benefit of the quick turnaround day between three shift days and nights also falling on a Sunday.

DuPont 12-Hour rotating shift example:

Week Fri Sat Sun Mon Tues Weds Thurs
1 Nights Nights Nights Nights Off Off Off
2 Days Days Days Off Nights Nights Nights
3 Off Off Off Days Days Days Days
4 Off Off Off Off Off Off Off

Five and twoEdit

The five and two provides 24/7 coverage using 4 crews and 12-hour shifts over a fortnight. Average hours is 42 per week but contains a 60-hour week which can be challenging.

Five and two shift example:

Week Fri Sat Sun Mon Tues Weds Thurs Fri Sat Sun Mon Tues Weds Thurs
1 Nights Nights Nights Off Off Nights Nights Off Off Off Days Days Off Off
2 Days Days Days Off Off Days Days Off Off Off Nights Nights Off Off
3 Off Off Off Swing Swing Off Off Swing Swing Swing Off Off Swing Swing
4 Off Off Off Days Days Off Off Days Days Days Off Off Days Days

Seven-day eight-hour rotating shiftEdit

The seven-day eight-hour rotating shift provided 24/7 coverage using 8-hour shifts with 14 crews. Consisted of a morning shift from 07:00 to 15:00, a swing shift from 15:00 to 22:30 and a night shift from 22:30 to 07:30 Each shift was worked for five days straight. The 8-hour shifts allowed vacations and absences to be covered by splitting shifts or working double shifts. The run of day shifts was 56 hours but the 8-hour shift provided time for some socializing after work. Was once common in the pulp and paper industry in the Western United States but has been largely replaced by a 8 days, 8 swing, 5 nights, 9 off, 8-hour rotation.

Seven-day eight-hour rotating shift example:

Week Sun Mon Tues Weds Thurs Fri Sat
1 Day Day Day Day Day Off Off
2 Swing Off Off Swing Swing Swing Swing
3 Night Night Off Off Night Night Night
4 Day Day Day Day Off Off Day
5 Swing Swing Swing Swing Swing Off Off
6 Off Night Night Night Night Night Off
7 Off Off Day Day Day Day Day
8 Swing Swing Swing Swing Swing Off Off
9 Night Off Off Night Night Night Night
10 Day Day Off Off Day Day Day
11 Swing Swing Swing Off Off Swing Swing
12 Night Night Night Night Off Off Night
13 Day Day Day Day Day Off Off
14 Off Swing Swing Swing Swing Swing Off
15 Off Off Night Night Night Night Night

SixesEdit

Submarine sailors in the American Navy engage in a pattern known as sixes while underway. Instead of a 24-hour day, the ship operates on an 18-hour schedule. Any given individual is scheduled to stand watch for 6 hours, perform any other duties and engage in leisure time for 6 hours, then sleep for 6 hours. If enough personnel are available, a given watchstation may benefit from a fourth man referred to as the midnight cowboy. He will 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, which is most often shortened to just cowboy) and the person who would normally stand that watch is free. This gives rise to a schedule of six on, twelve off, six on, thirty off, six on, twelve off.

Graveyard shiftEdit

Graveyard shift, night shift or third shift (3rd shift) means a shift of work running through the early hours of the morning, especially shifts from midnight until 08:00 or from 23:00 until 07:00. There is no certainty as to the origin of this phrase; according to Michael Quinion it is little more than "an evocative term for the night shift … when … your skin is clammy, there's sand behind your eyeballs, and the world is creepily silent, like the graveyard."[2]

In 2007, the World Health Organization (WHO) announced that working the graveyard shift would be listed as a "probable" cause of cancer.[3][4][5]

On-callEdit

Employees who work on an on-call basis have no regular schedule. They agree as a condition of employment to report to work when they are called, 24 hours a day, 7 days a week. This is particularly common in American railroad employment, especially for train crews.

Firefighting schedulesEdit

In many departments, firefighters work 24-hour shifts. They are authorized to sleep in the fire station at night but are still subject to calls for service the entire shift. Most departments split the 168 hour long week between 3 or 4 work groups (sometimes referred to as 'shifts' or 'platoon groups'), resulting in a 56 or 42 hour workweek, respectively. Some departments reduce the average workweek by scheduling an extra day off for each firefighter in the work group, frequently reducing a 56 hour workweek to a 48 hour workweek by scheduling a 24 hour "Kelly Day" every three weeks. Departments have many options for scheduling firefighters for coverage. One option is 24 on/48 off, where a firefighter will work 24 hours and have 48 hours off, regardless of the day of the week or the holidays. Often they will be scheduled in an A–B–C pattern. Thus, a firefighter will be assigned to A, B or C shift and work whenever that letter is on the calendar.

Most departments have found that a 24 hour work shift, with opportunistic sleeping between calls for service, is a valid means of avoiding some of the health and cognitive problems associated with shift work.

Three-Platoon schedulesEdit

24/48Edit

The most basic three-platoon schedule is a straight rotation of 24-hour shifts among three platoon groups. This rota limits time off to 48 hours in a row, less than 66 hours off in a row most workers get each weekend. Workers on this schedule only get one short weekend off every three weeks, making it difficult to perform the social grooming required to build the support networks necessary to deal with the stressors associated with emergency response. Twenty-four hours off-duty is also the minimum required to completely recover from a period of acute sleep deficit.[6]

Week Mon Tues Wed Thur Fri Sat Sun
Week 1 A B C A B C A
Week 2 B C A B C A B
Week 3 C A B C A B C


California roll shift scheduleEdit

Another option is known as a California roll, where some shifts will be close together but allow for several days off. This option gives a 96 hour break every 9th day, which is contiguous to the conventional weekend on two of nine weekends, with a third weekend providing a break that starts on Saturday morning. There is an opportunity to accumulate sleep debt over the three days of work, however this debt should be completely cleared over the four day break. The nine-day rota that is repeated to fill the calendar is this:

Time Sat Sun Mon Tues Wed Thur Fri
Week 1 07:00 to 07:00 A B A C A C B
Week 2 07:00 to 07:00 C B

where a firefighter will work 24 hours on, 24 off, 24 on, 24 off, 24 on, 96 hours (4 days) off.

Modified California RollEdit

This rotation reduces the chronic sleep deficit accrued over the first two work days at the expense of a shorter long break. This schedule's long break coincides with a standard weekend exactly once every nine weeks. The four day break could be retained by working a fourth day in the rotation - XOXOOXOXOOOO.

Time Sat Sun Mon Tues Wed Thur Fri
Week 1 07:00 to 07:00 A B A B C A C
Week 2 07:00 to 07:00 A B C B C

where a firefighter will work one day, off one, work one, off two, work one, off four days.


48/96Edit

A number of departments have investigated further work consolidation by allowing for a 48 hour work shift. Careful demand management would be required to avoid acute sleep deficit, however, firefighters should return to work fully recovered from the previous shift. [7]

3-3-3Edit

Kenneth B. Ellerbe chief of the District of Columbia Fire and Emergency Medical Services Department has proposed a schedule where firefighters work three day shifts, followed by three night shifts, followed by three days off.[8] It is likely that such a schedule would impact all four alertness factors associated with shift work, and result in a threat to public safety. It would result in exactly one break coinciding with the standard weekend every nine weeks. DDDNNNOOODDDNNNOOO

Four-platoon shift schedulesEdit

24/72Edit

The most basic four-platoon schedule is a straight rotation of 24-hour work shifts between four work work groups or platoons. This schedule works 48 hours per week for three weeks and 24 hours the fourth week, averaging 42 hours per week.

Week Mon Tues Wed Thur Fri Sat Sun
Week 1 A B C D A B C
Week 2 D A B C D A B
Week 3 C D A B C D A
Week 4 B C D A B C D
24/48/24/96Edit

Another variation of the 24-hr shift schedule is a 4-platoon system, averaging 42 hours/week. Thus, the schedule is 24 on, 48 off, 24 on, 96 off, on a 4-day rotation.

Week Mon Tue Wed Thu Fri Sat Sun
Week 1 A D B A C B D
Week 2 C A D B A C B
Week 3 D C A D B A C
Week 4 B D C A D B A
Week 5 C B D C A D B
Week 6 A C B D C A D
Week 7 B A C B D C A

Although the performance benefits of shorter shifts may not outweigh the performance costs of consecutive nights of work, some departments with four platoon groups work shorter shifts. Most such departments work a 10 hour day and a 14 hour night tour.[6] This enables the firefighter to get relieved from work in the afternoon, commute home, spend time with family, and get a good night's sleep before returning to work in the morning. Schedules that only allow 12 hours, or less, between work shifts do not allow enough time to incorporate a healthy night of sleep, and therefore begin to accumulate sleep deficit even when the employee is working days.

2-2-4Edit

On this schedule, firefighters work two 10 hour days, two 14 hour nights, and then have four days off. In the Canadian Firefighter study, consecutive nights were shown to be more deleterious to performance than a single, long shift. After two consecutive nights, performance effectiveness was reduced to 75%, vs. 78% on a 24 hour shift. If the schedule induces sleep deficit during the day shift, this performance would be worse. This schedule's long break aligns with the conventional weekend for exactly two weeks out of eight. The rota is: DDNNOOOO.

2-2-3Edit

This schedule is also known as the Panama Schedule above, however, when firefighters work it, the shifts rotate from days to night between every break. Since the firefighters have a two day break before any nights worked, they do not start the series of nights with an employment-related sleep deficit. They do work three nights in a row, which would result in chronic sleep deficit if alarms are received on each night, however, the third night is always a Sunday night, which is often less busy than other nights of the week. This schedule allows for a long break every other weekend. The rota is DDOONNN OODDOOO NNOODDD OONNOOO

ReferencesEdit

  1. 1.0 1.1 ORDER NO. 4-2001 REGULATING WAGES, HOURS AND WORKING CONDITIONS IN THE PROFESSIONAL, TECHNICAL, CLERICAL, MECHANICAL AND SIMILAR OCCUPATIONS. INDUSTRIAL WELFARE COMMISSIO. URL accessed on 15 February 2012.
  2. "Saved by the Bell", Worldwidewords.org, March 27, 2000
  3. [1] An estimated twenty percent of the American labour force works the night shift.
  4. Overnight shift to be classified as 'probable' cancer cause", CNN, November 29, 2007
  5. http://www.thelancet.com/journals/lanonc/article/PIIS147020450770373X/fulltext
  6. Cite error: Invalid <ref> tag; no text was provided for refs named canadian
  7. Departments on 48-96. 48-96.com. URL accessed on 13 February 2012.
  8. includeonly>Smith, Ed. "A shift toward sleep deprived firefighters", 2011-12-30. Retrieved on 13 February 2012.

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