How the cycle runs
Each crew's 14 days look like this: work 2, off 2, work 3, off 2, work 2, off 3. Two crews cover days and two cover nights, and the crews either stay on fixed days or nights or swap after each cycle. Over 28 days every crew works 14 shifts of 12 hours, which averages 42 hours a week.
Advantages
- Every second weekend is a three-day break.
- No more than three consecutive shifts.
- Only four shift changes a day between crews, with a fixed handover time.
- Simple to remember: the pattern repeats every two weeks.
Disadvantages
- 12-hour shifts, so fatigue rises late in the shift and after three in a row.
- 42-hour average needs overtime rules or a fifth relief crew.
- The day-night swap, where used, disrupts sleep every cycle.
- Training, meetings and maintenance windows have to fit around four crews that rarely overlap.
Panama, DuPont and 4-on-4-off
The DuPont schedule runs a 28-day cycle with a seven-day break but up to four consecutive nights. The 4-on-4-off pattern is simpler but gives weekends off less often. Panama is chosen where the weekend break and the short run of shifts matter most.
Shift patterns and daily management
Any 24/7 pattern means the same line is run by four crews who seldom meet. The daily management system is what holds them to one standard: the shift handover record passes status and open actions between crews, each crew's Tier 1 huddle starts from it, and the Tier 2 meeting sees problems across all four, so a fault that one crew works around is not rediscovered by the next three.