Better work shifts and sleep schedules have improved the health and safety of the Philadelphia police force.

As a result of the change in shifts, officers are performing better, living longer, and are around well after retirement.

-Captain Lou Campione

Shift work is inevitable in many jobs, including emergency services such as fire fighting and police work. But shifts—particularly when they involve changing schedules—night hours, and irregular sleep times are a major cause of insufficient sleep and can have deadly consequences on or off the job. These consequences take the form of increased risks of safety and health problems, including accidents due to drowsy driving, on-the-job injuries, cardiovascular disease, and cancer.

Working Against the Body's Clock

Shift work is often defined as working a schedule other than the usual 9 a.m. to 5 p.m. daytime hours. Since our bodies are programmed to be active during the day and to get rest at night, any work that requires activity during night hours may be disruptive.

The greatest risk of disruption comes when changing from day work to night work. Many shift workers rotate their shifts, working some days and some nights, and having varying numbers of days off. Depending on how this rotation is organized, sleep deprivation can be a major problem. One example of a problematic rotating shift was a schedule used by the Philadelphia police force. For many years, this schedule required officers to rotate among three different shifts, with a "backward" rotation (one week from 7 a.m. to 3 p.m., the next week from 11 p.m. to 7 a.m., and the third week from 3 p.m. to 11 p.m.). Changing from one shift schedule to another each week in this way is disorienting to the body's internal clock. In this situation, the body's sleep-wake schedule is continually disrupted—the body is sending out signals to sleep during the night shift, making it difficult to stay alert, and sending out signals to stay awake during the day, when the night shift worker is trying to sleep. Over time, the body's internal clock can adjust somewhat to a properly designed night or rotating schedule, but the type of rapid backward rotation the Philadelphia Police Department was using made it impossible for officers to ever fully adjust.

Lou's Story

Captain Lou Campione has been an officer with the Philadelphia Police Department for over 25 years. Back in the early 1980s, the backward shift rotation was in effect, and led to numerous complaints from officers of fatigue and job-related accidents and injuries. There were also high rates of hypertension and cardiovascular disease, with many officers dying before reaching retirement age. Lou worked with Robert Hurst, the president of the Fraternal Order of Police Lodge #5, and the Philadelphia Police Department to organize a study of police work schedules. They sought out Dr. Charles Czeisler, an expert in circadian biology and sleep medicine at Harvard Medical School, to lead the research.

Better Work Shifts Save Lives

The results of the yearlong study revealed that changing the work schedule from a counterclockwise shift rotation (that went against the body's internal clock) to a clockwise rotation (that was in sync with the biological clock) and staying on each shift for a longer duration to facilitate the body's adjustment resulted in a dramatic decrease in daytime sleepiness and on-the-job drowsy driving accidents. This schedule improved officers' alertness and job satisfaction, and may have improved their health. A variation of this new schedule was eventually adopted throughout the city of Philadelphia, resulting in greater productivity, better performance, and increased safety for police officers and for the citizens of Philadelphia who depend on them.

Lou's story is an exceptionally dramatic example of how an intervention to restructure the schedules of police officers was shown to save lives and improve safety. But even if a shift schedule is not as disruptive as the previous Philadelphia Police Department's schedule was, there are things most shift workers can do to improve their sleep health.

Learning from Lou's Story: What You Can Do

  • A challenging, shifting work schedule and a schedule where individuals routinely work the night shift can put you at risk for sleep deprivation. See Adopt Good Sleep Habits for tips on how to maximize the quantity and quality of the sleep you get.
  • Understand how your body's internal clock can help you get the most out of your sleep, even if you do not work at night or in rotating shifts. See The Drive to Sleep and Our Internal Clock in the Healthy Sleep module.
  • Some workplaces have instituted policies that support the health and safety of individuals who work at night or in rotating shifts. Bright lights, nap breaks, and work hour limits can all contribute to a better work environment. For more information, see Make Changes at Work.
  • Sleep deprivation, which is often a byproduct of shift work, affects not only your health, but also your judgment and the safety of others. Take the  How Awake Are You? interactive challenge to find out how sleep deprivation affects reaction time.
  • Sometimes shift workers may suffer from a sleep disorder that affects the quality of their sleep. If this is a concern, see When to Seek Treatment in the Healthy Sleep module.
  • Sleep is one of the three pillars of health. Take sleep seriously—make it as much of a priority as the other two pillars, good nutrition and exercise.