Firefighters are not machines; they need sleep.

The quote “I’ll have plenty of time to sleep when I am dead.[i]” is a self-fulling prophecy. Lack of sleep is an early death sentence, and firefighters are finding out the hard way.

Call volume is rising, fire departments are stretched thin, and the burden is affecting firefighters’ health by keeping them awake for multiple days at a time. Studies from around the world confirm sleep deprivation increases susceptibility to cancer, cardiac disease, and post-traumatic stress disorder (PTSD).


“Routinely sleeping less than six or seven hours a night demolishes your immune system, more than doubling your risk of cancer.”[ii]
-Matthew Walker

Cancer is the pressing issue for the International Firefighters Associations (IAFF). The reason is obvious, cancer as a cause of death for firefighters has spread, well, like cancer. The current narrative focuses on exposure to chemicals from fires, but recent evidence suggests there is more to it.

In 1996 Dr. Irwin of UCLA kept 42 healthy men awake between 10:00 pm and 3:00 am [iii]. The results showed a 70 percent reduction of cancer-fighting immune cells know as “natural killers” (NK) after one night![iv] NK cells are best known for detecting and controlling early signs of cancer.[v] In other words, one bad night at work dramatically reduces firefighter’s defense against early cancer and other diseases.

Natural Killer Cells targeting tumor

Dr. Irwin’s paper spawned a flood of studies drawing a strong correlation between sleep deprivation and higher rates of breast, prostate, colon, and endometrium wall cancer.[vi] The overwhelming evidence of higher cancer rates and lack of sleep caused Denmark to categorize cancer as presumptive for nightshift workers.

The evidence supports quality sleep can lower cancer rates in firefighters.

Heart attacks

“The shorter your sleep, the shorter your life.”
-Matthew Walker

45% of on-duty firefighter deaths result from cardiac events[vii]. We typically blame heart disease on fitness and diet, but a 2011 international study concluded that sleep deprivation increases risk of a cardiac event by 46%, regardless of diet or fitness.[viii] A 1996 study showed blood pressure increases following a night of bad sleep due to higher sympathetic nervous system activity. This demonstrates the correlation between sleep and heart attacks.[ix] Further supporting the 1996 study, the University of Chicago found people who sleep five to six hours each night or less were 200% to 300% more likely to suffer calcification of coronary arteries.[x]

Lack of quality sleep could explain why cardiac events are common in firefighters, regardless of fitness programs. Firefighters are eating better and excercising more, but they are also sleeping less.

In addition, sleep aided by medications or alcohol compounds problems. When the mind is sedated by sleep medications or alcohol, it cannot enter MREM sleep, an essential part of processing memories. And the inability to process memories can lead to PTSD.


“I love sleep. My life has the tendency to fall apart when I’m awake”
-Ernest Hemingway

Rosaline Cartwright, professor of psychology in neuroscience, explains the mind needs sleep to processes stressful events. Without sleep the brain cannot decouple the memory of tragic events and the physiological response. Essentially, if you can’t sleep on it, you can’t get over it. This explains a new epidemic in the fire service; firefighter suicide.

Cartwright’s research suggests the mind needs dreams followed by REM sleep and to process upsetting experiences. In other words, you have to recreate tough experiences in your dreams so your mind can break them down. Without the combination of REM sleep and dreams, memories of traumatic events remain fresh in the persons mind. As a result, a firefighter who is sleep deprived accumulates traumatic events like a trash can that is never emptied.

Leading to erratic thoughts and actions, sleep deprivation generates a form of schizophrenia. Lack of sleep removes one’s ability to process emotions. Unprocessed emotions from previous events become entangled with current events, producing irrational reactions to everyday situations. Unable to understand their own emotions, thoughts, or actions, people with sleep deprivation commonly become frustrated and develop suicidal ideations.

Firefighters who experience traumatic events are typically deprived of the one tool needed to process the memories; sleep. The lack of sleep creates a form of schizophrenia, leading to suicidal thoughts.[xi]

Contributing to cancer, cardiac events, and PTSD, lack of sleep may be the greatest cause of firefighter deaths.


When we discuss these findings, the typical response I hear is, “ this explains why we need to get rid of the 48 hr shift.” Interesting enough, the 48 hr shift was an attempt to lessen the effects of long-term sleep deprivation by consistently providing a long enough break to support a reset of the sleep schedule. This evidence supports the move from 24 hr shifts to 48 shifts in busy departments.

But regardless of shift schedule, I fear we are missing the true problem; a 56 hour work week. No matter how you dice up the shifts, 56 hr work weeks are wearing us out. When the fire service agreed to work a 56 hr week, it was cost-saving for the community. Firefighters agreed to work an additional 16 hours per week at straight pay and forgo the overtime pay. This schedule was negotiated on the concept that firefighters would have a standard business day, followed by remaining hours “on-call”. No one imagined that the “on-call” portion of the day would keep crews awake for 24hrs at a time.

Now we find ourselves in a pickle, high call volume keeps crews working 24 hours at a time and it is too expensive for communities to staff a fire department with 40 hour a week employees.

The evidence suggests that sleep deprivation increases the occurrence of cancer, cardiac disease, and suicidal thoughts. If we don’t find a solution soon, the cost to firefighters and communities may be devastating.

[i] Guy Sajer, The Forgotten Soldier

[ii] Walker, Matthew. Why We Sleep: Unlocking the Power of Sleep and Dreams (p. 3). Scribner.

[iii] Irwin, Michael, J. McClintick, C. Costlow, M. Fortner, J. White, and J. C. Gillin. “Partial night sleep deprivation reduces natural killer and cellular immune responses in humans.” The FASEB journal 10, no. 5 (1996): 643–653.

[iv] Irwin, Michael R., Minge Wang, Capella O. Campomayor, Alicia Collado-Hidalgo, and Steve Cole. “Sleep deprivation and activation of morning levels of cellular and genomic markers of inflammation.” Archives of internal medicine 166, no. 16 (2006): 1756–1762.


[vi] Walker, Matthew. Why We Sleep: Unlocking the Power of Sleep and Dreams (p. 184). Scribner. Kindle Edition.

[vii] Fahy RF. U.S. firefighter fatalities due to sudden cardiac death, 1995–2004. Quincy, MA: National Fire Protection Association, June 2005.

[viii] Cappuccio, Francesco P., Daniel Cooper, Lanfranco D’elia, Pasquale Strazzullo, and Michelle A. Miller. “Sleep duration predicts cardiovascular outcomes: a systematic review and meta-analysis of prospective studies.” European heart journal32, no. 12 (2011): 1484–1492.

[ix] Tochikubo, Osamu, Akihiko Ikeda, Eiji Miyajima, and Masao Ishii. “Effects of insufficient sleep on blood pressure monitored by a new multibiomedical recorder.” Hypertension 27, no. 6 (1996): 1318–1324.

[x] Walker, Matthew. Why We Sleep: Unlocking the Power of Sleep and Dreams (p. 166). Scribner. Kindle Edition.

[xi] Agargun, Mehmet Y., and Rosalind Cartwright. “REM sleep, dream variables and suicidality in depressed patients.” Psychiatry research 119, no. 1 (2003): 33–39.