Fatigue is an unavoidable vulnerability in the workplace, humans are not machines and need rest and recuperation to function properly. Fatigue describes feelings of tiredness, sleepiness, reduced energy and increased effort needed to perform tasks at a desired level. Fatigue affects our ability to think clearly, decreases our attention, our vigilance and our overall performance. The myriad of cognitive deficits caused by fatigue translates into decreased productivity, to the tune of up to $3,000 per employee annually.  Most importantly, fatigue is well-documented to increase a worker’s risk of injury in the workplace. One study showed that approximately 13% of work injuries could be attributed to sleep problems. 
Research has identified three main causes of workplace-related fatigue – time of day, sleep deprivation, and time on task. Anyone who has stayed up late into the early morning hours knows that it’s more difficult to function at 2am than at 2pm. This decreased performance takes a toll on night shift workers with a 30% higher risk of safety incidents. This is due to our circadian rhythm and the release of hormones, including melatonin. Individuals who need to be alert during the nighttime and sleep during the day are in a fight against their body’s own biology.
Experts concur, adults need to get at least 7 hours of sleep each night , but studies show that more than a third of Americans are not getting the appropriate amount of sleep.  A business person may feel obligated to answer emails late into the night, a medical resident may feel pressured to skip rest to take care of their patient, and a night shift worker may forego sleep to take care of kids during the day. The truth is, individuals who choose to skip sleep are more likely to suffer the debilitating effects of sleep deprivation.
As humans, our ability to remain focused on a task for an extended period of time is very limited. If the task demands constant attention, reaction or vigilance, a person will find themselves having to exert an increasing amount of effort to maintain the same performance over time. On the opposite spectrum, tasks that are tedious, unstimulating, and monotonous are also fatiguing as these tasks can unmask underlying tiredness. The longer the person is required to do the task the more fatigued they will get.
Other factors can contribute to a person’s fatigue, include workplace factors and sleep disorders. A worksite’s environmental factors and organizational factors, such as design, culture, policies and programs can promote or reduce the effects of fatigue. While some people may choose to forego sleep for other activities, others are struggling with sleep problems due to sleep disorders. Obstructive sleep apnea and insomnia are just a couple of the sleeping disorders that inhibit a person’s ability to get restorative sleep.
Many things can affect our levels of fatigue, from social obligations to technology use to our 24/7 workforce that requires us to neglect our body’s natural sleep patterns. The research is clear, safety performance decreases as employees become fatigued. National Safety Council encourages employers to learn about fatigue in the workplace, its costs, its causes and how fatigue can lead to a higher rate of safety incidents. We also encourage employers to educate their employees on how they can protect themselves from fatigue and fatigue-related problems.
Emily Whitcomb. Sr. Program Manager – Fatigue Initiative. National Safety Council.
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