Working Overtime Increases Risk of Workplace Injuries More Than Job Hazard, U.S. Study Finds

The long working hours culture drives up the risk of workplace injury and illness, reveals a study by occupational medicine researchers, who also conclude that the risk has nothing to do with how hazardous the job is.

After adjusting for age, gender, type of industry and job, employees working overtime were 61 percent more likely to sustain a work related injury or illness than employees who did not work overtime.

Working at least 12 hours a day was associated with a 37 percent increased risk of injury or illness, while working at least 60 hours a week was associated with a 23 percent increased risk, compared with those who worked fewer hours.

The more hours worked, the greater was the risk. But lengthy commutes had no impact on the injury/illness rate.

The U.S. researchers analyzed the responses of almost 11,000 Americans to the annual National Longitudinal Survey of Youth. The survey included questions about employment history, work schedules, and sick leave, covering the period between 1987 and 2000.

In total, 110,236 job records were analyzed, and 5,139 work related injuries and illnesses occurred. Over half of these were in jobs with extended working hours or overtime. In the U.S., up to a third of overtime is compulsory.

Further analysis indicated that the increased risks were not merely the result of demanding work schedules being concentrated in inherently “riskier” industries or jobs.

The authors say their findings back up the theory that long working hours indirectly precipitate workplace accidents by inducing fatigue and stress. They support government initiatives, such as those espoused by the European Union, to cut working hours.

Professor Allard Dembe, Center for Health Policy and Research, University of Massachusetts Medical School, Worcester, Mass, headed the study, which was published in the British Medical Journal.