The DuPont Schedule Explained: How the 12-Hour Rotation Works, a 28-Day Example Calendar, Overtime Math, and the Pros and Cons

What a DuPont Schedule Is

The DuPont schedule is a fixed, repeating shift rotation for operations that must be staffed around the clock. It takes its name from the chemical company where the pattern was first used for continuous-process plants, and it has since spread to utilities, refineries, hospitals, police and fire departments, data centres, mines and any operation where shutting down overnight is not an option.

Its defining features are four crews, 12-hour shifts and a 28-day cycle. At any moment two crews are working, one on days and one on nights, and two are off. Over the 28 days each crew rotates through both day and night blocks and ends the cycle with a full week off. Because the pattern repeats exactly every four weeks, employees can predict their shifts years in advance.

It is one of several 12-hour patterns used for 24/7 coverage. The others in common use are the Pitman (2-2-3) schedule, the 4-on-4-off schedule and the Panama schedule, all compared later in this guide. For an overview of rotation types in general, including 8-hour patterns, see our guide to rotating shift schedules.

The DuPont Shift Pattern Step by Step

One crew's 28-day cycle runs as follows. D is a 12-hour day shift (typically 7am to 7pm), N is a 12-hour night shift (7pm to 7am) and O is a day off.

1. Four night shifts (N N N N)
2. Three days off (O O O)
3. Three day shifts (D D D)
4. One day off (O)
5. Three night shifts (N N N)
6. Three days off (O O O)
7. Four day shifts (D D D D)
8. Seven days off (O O O O O O O)

That is 14 shifts and 14 days off in 28 days. Each of the four crews runs the same sequence, offset by one week, so that at every point in the cycle exactly one crew is on days and one on nights.

Read any column down and you will find exactly one D-shift crew and one N-shift crew for every day of the cycle. Read any row across and you will see each crew's 14 shifts, including the run of seven days off.

Hours and Overtime Under the DuPont Schedule

Fourteen 12-hour shifts is 168 hours per 28-day cycle, an average of 42 hours per week. That average is what makes the pattern attractive to employers: it is close to a standard full-time week while providing full coverage with only four crews. The weekly distribution, however, is very uneven.

Under the Fair Labor Standards Act, overtime for non-exempt employees is owed for hours over 40 in each fixed workweek. There is no averaging across weeks or across the cycle, so the 42-hour average is irrelevant for pay purposes. With the workweek aligned as in the table, each employee earns 48 hours of overtime per cycle, 8 of them in the first week, 32 in the second and 8 in the third, and nothing in the fourth. Across a year of 13 cycles that is 624 overtime hours per employee, which must be built into the labour budget from the start.

Two variables change the arithmetic. First, the employer's workweek definition: if the FLSA workweek starts on a different day from the cycle, the hours shift between weeks and the overtime total can change, though it cannot drop below the amount implied by a 72-hour stretch. Second, state daily overtime: in states such as California and Alaska, hours over eight in a day are overtime unless the schedule is adopted through a valid alternative workweek process, and even then hours over 12 in a day remain overtime. A 12-hour shift in California that was not approved by election costs four hours of daily overtime every shift. Our guide to what overtime is covers regular-rate calculation, and our compressed workweek guide explains the California election rules.

Night shifts on DuPont rotations are also commonly paid a shift differential, which must be included in the regular rate when calculating the overtime premium.

Pros of the DuPont Schedule

• Seven consecutive days off every four weeks. No other common 12-hour rotation offers a full week off without using vacation. Employees can travel or rest properly, and many describe it as the reason they accept the pattern.
• Fewer shift handovers. Two handovers a day instead of three reduces the moments when information is lost, which matters in process industries and healthcare.
• Full 24/7 coverage with four crews. The staffing requirement is predictable and the pattern never leaves a gap.
• Complete predictability. The 28-day repeat means shifts can be published a year ahead, which helps with childcare and second jobs.
• Fewer commutes. Fourteen shifts a month instead of twenty or more.
• Both day and night exposure for every crew, which spreads the burden of nights evenly rather than leaving one crew permanently on nights.

Cons of the DuPont Schedule

• The 72-hour week. Six 12-hour shifts in seven days, with a switch from days to nights after a single day off, is the most fatiguing week in any mainstream pattern. Fatigue research consistently finds error and injury rates rising in the later hours of 12-hour shifts and across consecutive shifts.
• Overtime cost. About 48 overtime hours per employee per cycle under federal rules, before any state daily-overtime rules.
• Rapid day-to-night switches. The single day off between the three-day block and the three-night block gives the body almost no time to adjust. Sleep specialists generally recommend forward rotation with longer gaps between direction changes.
• Irregular weekends. Weekends off fall unevenly across the cycle.
• Hard to cover absences. When someone on a 12-hour crew is sick, the replacement is usually a colleague already working 48 hours that week, and a 72-hour week can become 84.
• Unsuited to 8-hour operations or variable demand. The pattern assumes constant staffing needs around the clock.

DuPont vs Pitman vs 4-on-4-off

All three are 12-hour, four-crew patterns that deliver 24/7 coverage at an average of 42 hours a week. They differ in cycle length and in how the rest days are grouped.

Pitman and 4-on-4-off spread hours more evenly and never produce a 72-hour week, so they generate less overtime and less fatigue. DuPont trades that evenness for the seven-day break. Operations that poll their crews usually find a split: people with long commutes or family elsewhere favour DuPont, while people who prefer a steady rhythm favour Pitman. Some organisations run Pitman as fixed days and fixed nights, which removes direction changes entirely at the cost of leaving one crew permanently on nights.

Implementing and Tracking a DuPont Rotation

A DuPont rollout is a change to pay, sleep and family life for everyone on the floor, so the mechanics matter.

1. Model the labour cost first, including 48 overtime hours per employee per cycle and any shift differential, and compare it with Pitman and 4-on-4-off on the same headcount.
2. Check state law. In daily-overtime states, run the alternative workweek election before the first 12-hour shift, and confirm meal and rest break rules for 12-hour days.
3. Define the workweek in writing and keep it fixed. Changing the workweek start to avoid overtime is prohibited.
4. Consult the crews. Where a union is present, the pattern is almost always a bargaining subject. Where it is not, a vote still improves acceptance.
5. Set fatigue rules: minimum rest between shifts (11 hours is a common standard), limits on voluntary overtime after the 72-hour week, and a protocol for covering absences without creating 84-hour weeks.
6. Publish the calendar a year ahead and name the crews so swaps can be managed.
7. Track actual hours by shift and by workweek. Night shifts cross midnight, so the record must attribute hours to the correct day and workweek, and the system must not auto-deduct meal breaks that were not taken.

Manual timesheets struggle with shifts that start on one date and end on another. E-Monitor's time tracking records start and stop times per shift, assigns the hours to the right workweek and totals them against the 40-hour threshold automatically, so the 48, 72 and 48-hour weeks are visible as they happen. For the broader practice of monitoring round-the-clock teams, see our guides to employee monitoring for shift workers and monitoring night-shift and 24/7 operations.

Related reading: What Is a 9/80 Work Schedule?, How Many Hours a Day Are Employees Actually Productive?, How to Calculate the Fully Loaded Cost of an Employee.

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