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Risk Management Bulletin


By August 1, 2011No Comments

Fatigue plays a major role in shiftwork accidents. To improve the safety, health, and productivity of your shiftworkers, NIOSH recommends these guidelines:

  • Keep the schedule regular and predictable. Shiftworkers should know their schedules well ahead of time so that they can plan their sleep and rest periods. Past studies of train accidents show a correlation between irregular schedules and accidents.
  • Keep consecutive night shifts to a minimum. Some researchers suggest that employees should work only two to four nights in a row before taking a few days off. This keeps circadian rhythms (the body’s “clock”) from being overly disturbed and limits sleep loss.
  • Avoid quick shift changes. Avoid a break of only seven to ten hours before rotating to a new shift, such as from morning to night on the same day of the week. Such a rapid change, makes it difficult for a worker to get much quality rest before having to go back to work. When they return to work after a quick shift change, most workers feel tired and sleepy, which can lead to accidents. At the end of a night shift, it makes sense to have a break of at least 24 hours before rotating the worker to another shift. Some researchers even suggest a 48-hour minimum.
  • Avoid several days of work followed by four to seven-day breaks. Working for several days in a row followed by several days off can be highly fatiguing. Many shiftworkers find it difficult to return to the night shift after several days spent on a daytime schedule during their time off.
  • Keep long shifts to a minimum. If workers are doing 12-hour shifts, two or three shifts in a row should be the maximum. Avoid longer night shifts. When it’s not possible to avoid them, move heavy work to shorter or day shifts and lighter work to the longer night shift.
  • Examine rest breaks. Standard lunch and rest breaks taken during the shift might not be enough for night shift workers to remain safe and productive. In jobs that require repetitive physical work or great concentration, it’s better to have brief hourly rest breaks for recovery from physical and mental fatigue.
  • Be aware of high-risk periods. Managers and supervisors of night workers should be aware of the high-risk periods when workers might not realize that they’re tired. Most accidents occur between 1 a.m. and 6 a.m., near the end of the shift, when activity levels are high in the work area, or on the first two night shifts after working days or having days off.