Shift work is a type of work scheduling system that requires you to work outside of the standard morning to evening (such as 8 a.m. to 5 p.m.), five-day-a-week schedule. Many jobs require work shift schedules, particularly in businesses that are open 24 hours a day or in plants that require round-the-clock security or maintenance. These include–for example–some supermarkets and airports, as well as chemical and nuclear power plants. Types of work shift schedules include fixed, split, irregular and rotating shifts.

Fixed Shifts

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According to ergonomics4schools.com, fixed shifts require you to work the same amount of hours, starting and stopping at the same times, for a specified period of days. These types of shifts are typically utilized in static, non-rotating systems, wherein workers work the same shifts regularly. According to rotas.co.uk, an example of a fixed shift is a nightshift, wherein you are permanently assigned to work the same hours each night, with no switching over to dayshifts.

Split Shifts

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Split shifts require you to work at two or more different times each day. The “split” refers to the daily, unpaid break or breaks you take in between paid shift work. According to the Idaho Career Information System at cis.idaho.gov, one example of a job that uses a split shift schedule is a school bus driver. The first part of the shift is driving children to school. While the children are at school, you go on break (the split), and once school is finished you pick them up, which is the second part of the shift.

Irregular Shifts

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According to rotas.co.uk, with irregular shift schedules, the times and durations of your shifts are variable or erratic, following no fixed temporal pattern (such as nighttime or daytime shifts). Also, employers may assign these shifts as particular needs or problems arise. Cis.idah.gov gives the example of a salesperson working a 10 a.m to 5 p.m. shift on one day, an 8 a.m. to 2 p.m. shift on another day, and a 1 to 9 p.m. shift on yet another day.

Rotating Shifts

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Rotating shift schedules–according to ergonomics4schools.com–require that you work at different times based on a pre-planned pattern. This pattern follows a particular speed and direction. The speed refers to the number of times you work a particular shift (with a particular start time) before moving or rotating to a different one, while the direction–either forward or backwards–refers to what shift you move to. For example, you could work the morning shift for three consecutive days in a row (so the speed is three days), and then move forward to working the afternoon shift for three days (which is a forward direction, because the afternoon comes after the morning).