Daylight Saving: The Effect on Workers


According to a recent NIOSH Science Blog, many questions remain on the effect of daylight savings on workers and the best strategies to cope with the time changes.

By moving the clocks ahead one hour in the Spring – this year, it’s March 20th – we lose one hour which shifts work times and other scheduled events one hour earlier. This pushes most people to have a one hour earlier bedtime and wake up time. In the Fall, time moves back one hour.  We gain one hour which shifts work times and other scheduled events one hour later thereby pushing most people to have a one hour later bedtime and wake up time.

It can take about one week for the body to adjust the new times for sleeping, eating, and activity (Harrision, 2013). Until they have adjusted, people can have trouble falling asleep, staying asleep, and waking up at the right time. This can lead to sleep deprivation and reduction in performance, increasing the risk for mistakes including vehicle crashes.

Workers can experience somewhat higher risks to both their health and safety after the time changes (Harrison, 2013). A study by Kirchberger and colleagues (2015) reported men and persons with heart disease may be at higher risk for a heart attack during the week after the time changes in the Spring and Fall.

The reason for these problems is thought to be disruption to circadian rhythms and sleep. Circadian rhythms are daily cycles of numerous hormones and other body functions that prepare us for the expected times for sleeping, eating, and activity. Circadian rhythms have difficulty adjusting to an abrupt one hour time change.

The online training program “NIOSH Training for Nurses on Shift Work and Long Work Hours” has many suggestions for coping with various types of work schedules and improving sleep. Although it was designed for nurses, the information is relevant to many occupations.

Part 1, Module 2 gives information about sleep and circadian rhythms and Module 4 discusses individual differences. In Part 2, Module 6 gives suggestions for improving sleep.