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Lack of sleep can lead to fatigue in the woods or on the farm.

Ever pulled an all-nighter or worked a 14-plus hour day? Do you or someone you know or work with have issues sleeping at night? If you can answer yes to one or both of these questions, you’ve experienced fatigue.

What does this have to do with forestry or farming? Per capita, logging is the deadliest profession in the United States with 132 fatalities per 100,000 workers. Almost 80 percent of the fatalities occur through contact with equipment or objects, 15 percent involve transportation incidents, about 5 percent occur from slips, trips, and falls, and the rest are attributed to miscellaneous. 

Farming/ranching is No. 8 on the list of the Top 10 deadliest jobs in the U.S. with 22 fatalities per 100,000 workers.

What’s unclear from investigations into fatalities are the real underlying causes of these unfortunate events. Many appear to be “freak” accidents, and perhaps they are all sheer coincidence. But might fatigue be the hidden culprit?

The primary cause of fatigue is not enough sleep and research into automobile accidents shows that in 2013, over 72,000 automobile accidents were attributed to fatigued driving. Of these accidents, there were over 44,000 injuries and 800 fatalities.

Research also indicates that there is a 60 percent greater chance of occupational injuries associated with working overtime. Additionally, 12-hour work days lead to a 37 percent increase in hazard rates while 60-hour work weeks lead to a 23 percent increase in work related illness or injury.

How many of us get at least eight hours of sleep every night? The Centers for Disease Control recommends that adults get 7-9 hours of sleep each night. A recent straw poll of over 350 loggers and woods-workers attending the University of Idaho’s Extension Logger Education workshops shows that very few – less than 3 percent – get at least six hours of sleep a night.

Chronic sleep deprivation can lead to many physiological impairments in the human body, including cardiovascular, metabolic, and respiratory functions. Anything less than eight hours of sleep decreases time to physical exhaustion by 10-30 percent and among other things, decreases the body’s ability to sweat during physical exertion.

In short, this decreases an individual’s endurance and performance.

Inadequate sleep also decreases the immune system. Moreover, anything less than six hours of sleep more than doubles the risk of cancer, contributes to Alzheimer’s disease, disrupts blood sugar levels, makes you hungrier, and can lead to coronary artery blockage, cardiovascular disease, stroke, and congestive heart failure.

These facts are pretty sobering and should be a “wake-up” call (pun intended).

Research also shows that less than one week of sleep curtailment in healthy young people is associated with changes in metabolic and endocrine function, leading to decreased carbohydrate tolerance.

Chronic sleep deprivation predicts a massively higher risk of injury in athletes and it also leads to lower work production. One brain function that buckles under even the slightest amount of sleep deprivation is concentration and a major consequence of a lack of concentration due to sleep deprivation is in the form of drowsy driving.

Driving performance after 18 hours of work is equivalent to driving with a 0.05 percent blood alcohol content, while driving after 24 hours of work is equivalent to driving at 0.10 percent blood alcohol content.

Fatigue has several dangers but the main one is reduced safety due to substantial cognitive impairment leading to decreased situational awareness. Working long days for 7-14 days requires at least three nights of eight hours of sleep to recover. Hopefully, we are creating a picture for you of perhaps why accidents may happen in the woods, or on the farm or ranch.

We have been conducting fatigue and sleep research on wildland firefighters (online, see with plans to monitor loggers during the fall and winter of 2019. Using technology developed by the U.S. Army Research Lab, we can track the quantity and quality of sleep wildland firefighters get each night and compare their on-fire vs. off-fire times.

This technology uses the sleep data to provide a fatigue rating (or alertness score) on a scale of 0-100. A score of 90 or less means the person is fatigued and reaction times are slowed and blood alcohol equivalents can be seen in Table 1.

To further illustrate this, using the monitoring technology mentioned above, column 2 in Table 1 lists the alertness scores and percentage of time Randy Brooks, the co-author of this article, spent in each alertness zone based on sleep quantity and quality from July 1 to July 31. Only 57.4 percent of the time that month was spent in the high alertness zone.

More importantly, 5.1 percent of the time was spent in a low state (0-70) of alertness where reaction time was slowed by 55 percent or more which is equivalent to a blood alcohol concentration of 0.08 percent or greater with a high risk of accident or serious error.

Now imagine yourself working in the woods or on the farm or ranch and your reaction time is reduced by half or more. Could this be a reason behind many close-call accidents? That remains to be seen, but it’s something we are working on.

Table 1. Alertness scores defined and the percent of time the author spent in each zone.

Alertness Score (zones)

% of Time Spent in Each

Reaction Time Reduction

Blood Alcohol Equivalence

Risk of Accident or Serious Error

91 - 100




Very Low

81 - 90





71 - 80





61 - 70





0 - 60




Very High


What can we do to improve sleep and reduce fatigue? We’ve used the term BMPs (Best Management Practices) in this column frequently, so we recommend the following BMPs for sleep. CDC recommends 7-9 hours of sleep each day in order to function at the highest level of effectiveness, physically and mentally.

Additionally, according to Dr. Matthew Walker, “In the context of injury there is no better risk-mitigating insurance policy than sleep.”

What follows is a bulleted list of practices we can all implement to try to help us get better sleep and consequently, reduce fatigue:

* Reduce caffeine, alcohol, screen technology, and have a cool bedroom.

* No caffeine after 2 p.m.

* No alcohol three hours prior to bed. Alcohol induces the liver to produce ketones and aldehydes, which actually wake us up.

* Establish regular bed-time and wake-up times. This is the single most effective BMP.

* Go to bed when sleepy, avoid couch dozing after work.

* Don’t lie in bed awake, get up and do something relaxing.

* Reduce anxiety-provoking thoughts and worries. Unwind and relax.

* Remove visible clock faces to prevent clock watching.

* Restrict time in bed – stay awake longer.

* Build up sleep pressure.

* No exercise less than two hours prior to bedtime. Keep your body temperature low and reduce your metabolic rate.

* Take a hot bath. It relaxes you and as your body temperature drops, you feel sleepy.

* One-hour exposure to natural sunlight – it’s important for keeping circadian rhythm (our biological clock) in check.

 * Eating a high-carbohydrate meal pre-bedtime equals less deep sleep and more awakenings.

* Avoid being too full or too hungry.

As a disclaimer, this list is a generalization and can be found by googling “sleep hygiene tips.” If you have sleep issues, please consult a physician.

We will close with one more question? How many of you conduct maintenance on your equipment – tractors, cars, trucks, chainsaws? We are all good at maintaining our equipment, so why don’t we maintain our most important piece of equipment – our bodies?

This can be accomplished in part by getting more sleep. By doing so, we may be able to reduce our fatigue levels and possibly avoid an accident. For information on body composition changes in wildland firefighters that we have been researching, see our article online here:

Randy Brooks is an Extension forestry specialist for the University of Idaho and Callie Collins is his Ph.D. student also located at the University of Idaho.