DuPont Shift Schedule: 28-Day Rotation and Calendar

The DuPont pattern combines compressed 12-hour work blocks, rapid changes between days and nights, and its defining seven consecutive days off at the end of each cycle.

For one crew, a commonly documented sequence is:

4 nights → 3 off → 3 days → 1 off → 3 nights → 3 off → 4 days → 7 off

All four crews follow the same 28-day sequence from different starting points to cover day and night operations.

A week-by-week DuPont calendar

This example starts on a Monday. “Day” and “Night” represent 12-hour shifts; use your employer’s actual times.

Week	Mon	Tue	Wed	Thu	Fri	Sat	Sun	Hours
1	Night	Night	Night	Night	Off	Off	Off	48
2	Day	Day	Day	Off	Night	Night	Night	72
3	Off	Off	Off	Day	Day	Day	Day	48
4	Off	Off	Off	Off	Off	Off	Off	0

The weeks look extremely uneven, but the full cycle contains fourteen shifts. At 12 hours each, that is 168 scheduled hours in 28 days, or 42 hours per seven days on average.

The table is schedule math, not a promise about overtime or pay. Employers and jurisdictions can calculate those differently.

How the day and night changes work

This pattern changes from nights to days after three off days, then returns to nights after only one off day. That single off day is one of the most important details to see correctly in a calendar: a night shift also ends the following morning, so the practical recovery window is not always as large as the word “off” suggests.

Record each overnight shift from its true start time to its true end time. Do not mark both calendar dates as separate work shifts.

Advantages and disadvantages

Possible advantages

• A full seven-day rest block appears once per 28-day cycle.
• Only fourteen commute days are scheduled in four weeks.
• A fixed 28-day sequence can be planned months ahead.
• Four staggered crews can provide continuous coverage.

Possible disadvantages

• One calendar week contains six 12-hour shifts, or 72 scheduled hours.
• The rotation changes between days and nights within the same cycle.
• Four consecutive night shifts can be demanding.
• Personal plans can be disrupted if overtime is added to the long break.

Who commonly works a DuPont schedule?

The pattern is associated with round-the-clock industrial and safety-sensitive operations, including manufacturing, utilities, processing facilities, and control rooms. A US Pipeline and Hazardous Materials Safety Administration resource documents the DuPont plan as a four-crew, 12-hour, 28-day rotation used in pipeline control-room settings.

The name is still not enough to build your calendar. Some workplaces use a modified DuPont schedule, training days, relief weeks, or different transition rules.

What to confirm before entering the rotation

1. Which date is day one for your crew.
2. Whether your sequence begins with nights or at another point in the cycle.
3. The exact day and night start/end times.
4. Whether the seven-day block contains training, on-call duty, or scheduled relief work.
5. How swaps and overtime should appear without changing the underlying 28-day cycle.

For a simpler 12-hour rotation with no seven-day break, compare the 4-on-4-off shift pattern. For shorter work blocks and every-other-weekend structure, see the 2-2-3 schedule.

Fatigue and recovery are separate from calendar accuracy

The PHMSA shift-plan resource identifies the four-night block as a key weakness of the pattern. The CCOHS rotational-shiftwork guidance also emphasizes shift length, recovery, workload, and rotation direction. Use the calendar to follow your confirmed roster, not to assess occupational safety.