Circadian Technologies

Advanced Shift Scheduling

This page will eventually contain examples of different shift schedule possibilities, as soon as I compile the data into tables suitable for the web. —Chuck Whitt

Study of 8 vs. 12-Hour Shifts with Texas Chemical Plant Operations

• Plant utilizes both 8's and 12's simultaneously
• Employees perform similar work on both schedules (107 workers on each)
• 7-1, 7-1, 6-4 "Southern Swing" vs. 4on - 4 off 12-hour schedule
• Higher social life satisfaction with 12's, despite higher overtime than with 8's
• Higher overall health index with 12's
• Higher sleep quality/quantity with 12's on work days/nights
• Overall, the workers on 12's fared better than those on 8's, even though they worked overtime each week.

Source: Michael Smolensky, Southern Medical Journal (Vol. 89, No 3, pp. 305-311), March 1996

Study of Chemical Workers in the U.K. Comparing 8 vs. 12-Hour Shifts

• Some improvement in health and physiological well-being with 12-hour shifts

• Significantly more social and domestic disruption with 8-hour shifts

• Little difference in job satisfaction, but better acceptance of shiftwork reported by those working 12's

• No difference in quality/quantity of sleep after night shifts

• Some improvement in alertness levels with 12's depending on time of day

• "Results are explained in terms of the design of the 12-hour shift systems and the specific sequencing of shifts that seem to minimize the potential for the build-up of fatigue."

Source: Phillip Tucker, Simon Folkard, et al., Occupational and Environmantal Medicine, Comparison of Eight and 12-hour Shifts: Impacts on health, wellbeing, and alertness during shift, 1996; 53: 767-772.

Home