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    March 16, 2020

    Understanding Workplace Safety Hours

    In the U.S., workers are praised by their bosses when they pull extra hours, stay late, work overtime. With an ultra-competitive job market, hiring comes with the unspoken statement that staying extra hours beyond the good old 9-to-5 is expected.

    But those extra hours have a huge impact on worker health – and the safety of the whole workplace.

    Here’s what your team needs to know about workplace safety hours, no matter what industry you work in.

    How Many Hours Can You Work in a Day?

    The answer to this question is:  it really depends! 

    It may seem logical for OSHA to regulate the number of hours a person can work under the guise that working too many hours could be unsafe however, at the present time, there is no such regulation. At best, if the hours worked by employees constitutes a recognized and correctible hazard that has either caused or is like to cause serious harm or death, then it could be a violation of the General Duty Clause (section 5(a)(1) of the Occupational Safety and Health Act)—but that would be a stretch.

    However, just because federal OSHA doesn’t regulate the number of hours a person can work doesn’t mean there aren’t other regulatory agencies that DO put a limit on work hours. 

    For example:

    • The Department of Labor under the Fair Labor Standards Act (FLSA) has very specific rules for how many hours a person under the age of 18 can work within certain industries covered by the FLSA and within those industries that are covered under the grandfather coverage provisions of the FLSA. In addition, the FLSA also provides regulations for what industries persons under the age of 18 can be employed.  These federal regulations are often in addition to separate state regulations for youth workers.

    • The Department of Transportation (DOT) through the Federal Motor Carrier Safety Administration (FMCSA) regulates hours of service for those people who operate a commercial motor vehicle to carry both property and passengers.

    • The Federal Aviation Administration (FAA) has regulations specifying the flight, duty and rest requirements for flight crews operating under 14 CFR Part 121 (air carriers).

    • The Federal Railroad Administration has regulations limiting the hours of service for train employees who are engaged in commuter or intercity rail passenger transportation.

    • The Nuclear Regulatory Commission has regulations that limit the hours for workers employed at nuclear facilities.

    • The International Maritime Organization (IMO)’s International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW) outlines the requirements for both hours of work and hours of rest for those working in the maritime industry.

    • Through the Health Care Personnel Enhancement Act of 2004, the Department of Veterans Affairs provided guidelines for limiting the work hours of nurses (except emergency room nurses) who provide direct patient care.

    • 18 states have laws that restrict mandatory overtime for those employed in the nursing industry.

    Worker Fatigue

    While long work hours contribute to a worker being fatigued, other factors such as working extended shifts and irregular shifts (like night shifts) also contribute.  Our bodies are naturally programmed to be awake during the daylight hours and asleep during the nighttime hours and when this is interrupted, the body doesn’t always adapt very well. 

    In addition to causing sleepiness and reduced alertness, worker fatigue has been shown to reduce motivation and decision making skills as well as the ability to concentrate.  When workers, especially those in safety sensitive jobs, are unable to concentrate and their decision making skills are altered, bad things happen.  Several very high profile disasters such as the 2005 refinery explosion in Texas City, the explosion of the space shuttle Challenger and the nuclear accidents at both Chernobyl and Three Mile Island all list worker fatigue as a contributing factor in those disasters.

    When sleep is interrupted or when the natural sleep cycle is altered, sleep can be less restorative which studies have linked to several other health issues such as heart disease, reproductive problems, depression, breast and prostate cancers, obesity and certain digestive issues.  In addition, prolonged fatigue has also been shown to cause diseases like diabetes and epilepsy to get worse.[1]

    Reducing the Hazards

    When we think about typical hazards in the workplace and find solutions to reduce or eliminate those hazards, we often don’t include the hazard of worker fatigue—but we should.  With a little effort, worker fatigue can be reduced just like most other hazards.

    For employers, one of the first steps to reducing the hazards of worker fatigue is to recognize there’s a problem. From there, OSHA recommends the following activities:

    • Examining staffing issues such as workload, work hours, understaffing and worker absences, scheduled and unscheduled, which can contribute to worker fatigue.

    • Arranging schedules to allow frequent opportunities for rest breaks and nighttime sleep.
    • Making adjustments to the work environment such as lighting, temperature and physical surroundings to increase alertness.

    • Providing worker education and training addressing the hazards of worker fatigue, the symptoms of worker fatigue, the impact of fatigue on health and relationships, adequate quality and quantity of sleep and the importance of diet, exercise and stress management strategies to minimize the adverse effects of fatigue.

    • Consider implementing a Fatigue Risk Management Plan under which, like other risk factors, fatigue can be managed.

    For workers, the best thing that can be done to reduce fatigue is to gain a balanced approach to your overall health by focusing on getting good quality sleep (even if it’s not during the normal nighttime sleep cycle), exercising regularly and ensuring a balanced diet, going easy on the caffeine prior to bedtime.  You can find several terrific articles and other tools to help learn about worker fatigue and how to combat it on the National Institute for Occupational Safety and Health (NIOSH)’s website.

    Making the Most of Your Workplace Safety Hours

    You have a lot to get done in a single workday. Knowing the limits on your workday is critical for more than just compliance–it’s the only way to ensure that your workplace safety hours aren’t put to waste thanks to a long shift.

    After all, when your team puts in long hours, you want to make sure that your workers are safe for every minute.

    Make sure to check out our blog for more posts on workplace laws and how workdays factor into your safety team’s considerations, like this post on the health effects of shift work.


    [1] Dembe A, Ericson JB, Delbos RG, Banks SM [2005]. The impact of overtime and long work hours on occupational injuries and illnesses: New evidence from the United States. Occup Environ Med 62:588_597.

    Katy Lyden, MS, OHST

    Katy Lyden is a Domain Analyst and EHS Subject Matter Expert for StarTex Software, the company behind EHS Insight. Prior to her current role, Katy spent 17 years successfully leading EHS programs for several large companies within the manufacturing industry. Katy is a Navy veteran, retired Emergency Medical...