Sleepiness and Fatigue

Sleepiness is a physiological manifestation and is most commonly seen late at night or in the afternoon when we have a propensity for sleep. Sleep deprivation compounds the physiological need. Sleepiness is usually associated with drooping head and/or eyelids and an inability to focus on visual or aural information.

Cognitive or mental fatigue, on the other hand, is a manifestation of exertion. The brain can only work for so long before it needs a break to consolidate what it has taken in and to prepare itself for more activity. Fatigue is usually manifested in detriments in judgment, reasoning, vigilance and decision-making.

Fatigue and sleepiness can go hand-in-hand if one has worked long hours and is sleep deprived. This is further complicated by the fact that sleepiness can be masked in high intensity situations such as an emergency or need to complete a project by deadline. If an error or accident results, was it fatigue or sleepiness?

Strategies for Health and Safety

The solution for sleepiness is to sleep. This may require getting more sleep while you are off work, limiting hours worked or having a nap (up to 20 minutes) at work, perhaps in the afternoon or at some point during the night.

Fatigue can be overcome through a variety of measures other than sleep. Short rest breaks (2 – 10 minutes) should be taken throughout the shift, day or night. Simply stopping the task for a few minutes may suffice, but one should also consider some stretches, deep breathing and drinking water.

Though it is useful to consider the benefits of napping, it is equally important to understand the value of short rest breaks and other fatigue-busting measures.

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