– Mark Twain
Human beings have a natural apprehension when it comes to fire. This natural impulse to flee from an unrestrained fire is perfectly normal. It is an essential skill for survival. Fire is one of the most essential tools that we as human beings possess, and it also has the potential to be one of the most destructive. The need to respect this "creature" is a cornerstone for being able to safely use fire in the myriad of ways that we do.
As parents we recognize the need to teach our children to avoid situations which may cause them harm. This training begins with essential survival skills ranging from "don't put anything in your mouth that isn't food," to "stay away from the stove, it's hot." When we are dealing with children who are younger than seven years old, when the child's level of cognitive ability is still developing, most of this training takes the form of a conditioned response. If the child starts to approach the stove or campfire they receive a sharp, loud yell from the parent, and in many cases a slap on the hand. The idea is straight forward: scare them and stop them in their tracks, or show them that going near the dangerous thing has painful consequences. There is no other way to teach our young children to avoid these dangerous situations. However this early, and often stern, method of imprinting a behavioral pattern also leads to individuals developing an apprehension of fire. As we mature we are taught how to safely use fire: to cook; to heat our homes; to create structures which were unimaginable to our ancient ancestors. Our early fear of fire is transformed into an understandable respect for fire and its power, but underneath that respect is the unchangeable imprint left upon our three-year old psyche of mom or dad slapping out hand when we reached for the stove.
Firefighters must behave in an abnormal way when they choose to enter a building that is on fire. Choosing to disregard the normal psychological response to fire by entering a burning structure causes an understandable stress reaction even in an experienced fireman. In order to operate safely and effectively on the fire ground we must understand the psychological and physiological reactions which affect our performance, and how to manage our stress responses. This is the part where I need to lay a foundation. It may seem a bit complicated, but understanding how your body reacts and why you respond in certain ways will help you to develop the skills to control your response.
The Physiology
Firefighting requires that an individual willingly enter an environment which poses a threat to his health and welfare, and while in that environment engage in strenuous physical activity while being hampered by the very protective clothing that is necessary to keep him from being burned, and disregard the undercurrent of fear which tells him he needs to flee. He must physically perform at the level of a Navy SEAL while maintaining situational awareness, anticipating the next steps to complete his assigned task and providing progress reports to his supervisor. Firefighting takes a toll on the firefighter both physically and psychologically. Through out the late 1990s and the early part of the 21st century a significant body of research has been conducted on the physiological effects of firefighting. Some of the most comprehensive work has been conducted by Dr. Denise Smith and Dr. Steve Petruzzello, collogues of mine at the Illinois Fire Service Institute. Their research continues, and is adding to the understanding that we must have of just how the human body reacts to the effects of firefighting.
Studying the physiological effects of firefighting is challenging because of the multiple variables which have to be considered: firefighters range in age from 18 to 70 years old; not every firefighter starts with a common level of physical fitness; differences in heredity and the way you were raised all play a factor in how your body will respond to the stresses that are place on it.
There are some conclusions that are consistently repeated across several studies. During firefighting operations firefighters reach their maximal, or near maximal heart, rate. Maximum heart rate is measured by subtracting an individual's age from 220 (i.e. the maximum heart rate for a 31 year old is 220-31=189 beats per minute [bpm]). Studies evaluating the heart rate of firefighters performing fire ground operations during interior structural firefighting operations show that heart rates between 164.1bpm to 183.5bpm are common.
In other words a 31 year old firefighter will be functioning at between 86.8% and 97% of his maximum heart rate while operating inside a structure fire. This level of physical exertion has multiple effects on the individual firefighter.
First the firefighter is increasing the level of thermal stress on the body because of the metabolic action required to perform the required actions. This metabolic stress can best be measured by the metabolic equivalent level (MET). One MET is the amount of energy/oxygen that your body uses while sitting quietly. Based upon studies by Barbara Ainsworth of the University of South Carolina firefighters can expend 12 METS of energy while conducting firefighting operations. This is the same level of energy expenditure seen in Navy SEALs, and professional boxers. As a comparison your body is working at roughly 13 METs if you are running 7.5 miles per hour (an 8:00 minute mile) at a 1% incline.
Second the firefighter must contend with an increase in thermal stress on the body from the elevated temperatures found inside a structure. Ambient air temperatures can rise above 449°F inside a burning building. At this level of ambient temperature the firefighter would not survive with out his protective ensemble of turnout gear and SCBA.
Third the firefighter must contend with the limitations placed upon his body by the very personal protective equipment that he needs to survive in the building. The National Fire Protection Association standard on firefighter safety, NFPA 1500, specifies that all firefighters shall use Coat, Pants, Boots, Gloves, Helmet and Protective Hood in conjunction with their SCBA. These elements of protective gear reduce the risk of the firefighter being burned through the use of fire resistant materials and layered structures. The unwanted effect of these garments is that the firefighter is less able to relieve heat stress through perspiration, as the insulating properties which prevent heat from burning him also trap his radiated body heat.
All of these aspects have been quantified through study into the physiology of firefighting. We can use the accepted standard of 98.6°F as the "normal" human body temperature. One study has shown that on average the tympanic temperature of firefighters completing 16 minutes of firefighting activity were elevated to 104.1°F, after operating in an atmosphere varying between 170.1°F and 199.9°F This physiological effect has been shown to reduce the heart's stroke volume, the amount blood the heart can pump in one contraction, and increase the dilation of blood vessels closest to the skin. These two factors can lead to a dangerous drop in blood pressure. This has potentially significant consequences, and it can be assumed that a number of the firefighter LODD which fall under the "Stress/Exertion" category are a result of this cardiac compromise.
If we assume that a firefighter equipped with the common "30 minute" SCBA cylinder is able to perform 16 minutes of work prior to exiting the fire building we can expect that he will exit the building with a body core temperature of 104°F and a pulse rate of 175bpm. Interestingly, research has shown that despite this level of physical exertion firefighters do not show a corresponding psychophysical effect.
The studies of Denise Smith and Steven Petruzzello have incorporated an evaluation of Rate of Perceived Exertion based upon the Borg scale. These studies examine the RPE based on physiological and psychophysical factors, but they do not take into consideration the purely psychological aspects. Based upon their research we can see that firefighters will rate their exertion as being "hard", a rate of perceived exertion that we would expect to see for a person with a heart rate of 150bpm, yet the recorded heart rates recorded should have elicited a response of "very hard" to "extremely hard". There is no clear clinical explanation for this variation. A component that must be considered is the subjective nature of measuring effort based upon the Borg Scale; it is all in the mind of the individual what "hard" means to him or her. Additionally we need to consider that the thermal stress, dehydration and the previously discussed cardiac compromise may affect the ability of the individual responder to accurately assess the level of exertion.
These physiological and psychophysical effects can be seen as having an effect on cognitive function as well. In the Smith's and Petruzzello's 1998 study subjects were assessed for their cognitive function after each of their three trials. Subjects were evaluated based upon their response time and degree of accuracy using a Continuous Performance Test. Response time decreased across all three trials. The authors' conclusion was that this could be attributed to the ability for neural signals to be transmitted more quickly across the warmed nervous system. The Continuous Performance Test used required the subjects to determine if a displayed number was a 0 or 9, or a number between 1 and 8. While this does provide some understanding of the basic response time of the nervous system, it is not an accurate predictor of how the individual's ability to analyze and respond to multiple sensory inputs while functioning in the fire environment. Even the United States Fire Administration acknowledges this, "The physical and mental demands associated with firefighting and other emergency operations exceed those of virtually any other occupation."
The Psychology
People assume that firemen aren't afraid of running into burning buildings. My experience has been to the contrary. When new candidates start in the fire service they have an understandable apprehension of what they are going to be called upon to do. We know that we are raised to have a fear of fire. That fear needs to be controlled however if we expect our firefighters to perform. In order to be able to control your psychological responses you need to understand the effect that fear and anxiety have on you. The psychological responses of firefighters to the environment and activities they face are an aspect of firefighting has not received a great deal of focus from researchers. We can use the work of researchers like Lt. Col. Dave Grossman, Bruce Siddle and Loren Christensen in to the psychology of men in combat to develop an understanding of some of the effects psychological stress that firefighters can be expected to cope with.
An understanding of the psychological reactions we confront must start with a brief understanding of our nervous system. Every person's nervous system is comprised of two main components: the somatic nervous system, which is responsible for the actions of our voluntary muscular movements; and the autonomic nervous system, which is responsible for all of the functions that our body needs to perform automatically. It is primarily the role of the autonomic nervous system that we are concerned with.
The autonomic nervous system functions through the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). These two systems send signals to your organs, muscles, and brain directing actions, and they work in opposite directions. The SNS is responsible for increasing your heart rate and respiratory rate, diverts blood flow away from your skin through constricting blood vessels, and other actions that would be considered a part of our body's "Fight" response. The PNS has the opposite effect, it slows your heart rate when the need to move large quantities of oxygen have been reduced, and moderates your digestion, and you bowl and bladder control. The PNS is your body at "Rest".
During high stress situations like combat, your body switches its resources from the PNS to the SNS: your pupils dilate to enhance your vision, your heart rate increases to move a greater quantity of oxygen to the large muscles needed to fight or flee and you peripheral circulatory system contracts so that if you are cut you will bleed less. The downside to this sudden switch is that things such as bowel and bladder control can be quickly lost. You can urinate or defecate right on the spot. This is something that isn't often understood, and it isn't something talked about often, but it does happen. In The American Soldier, a study of the actions of soldiers in World War II, one quarter of all soldiers reported the loss of bowel or bladder control in combat. Responders who survived the September 11th, 2001attacks on the World Trade Center reported numerous cases of uncontrolled loss of bowel and bladder control.
For firefighters the single most important side effect of the SNS taking primacy is the increase in heart rate. Emergencies are not scheduled events. When the alarm bell rings your heart rate begins to increase. Controlling that initial adrenaline dump is critical. The effects of an increasing heart rate because of anxiety have been documented by Lt. Col. Dave Grossman and Bruce Siddle. The chart below is based on their published work.
| Heart Rate | Physiological Reaction |
| 60 BPM | |
| 80 BPM | Normal resting Heart Rate |
| 90 BPM | |
| 115 BPM | Fine motor skill detriorates |
| 120 BPM | |
| 145 BPM | Complex motor skills deteriorate |
| 150 BPM | |
| 175 BPM | Cognitive processing deteriorates Loss of peripheral vision (Tunnel vision) Loss of depth perception Loss of near vision Auditory exclusion |
| Above 175 BPM | Irrational fight or flee |
| Freezing | |
| Submissive Behavior | |
| Voiding of bladder and bowel |
It is important to remember that these effects are only for stress induced heart rate increases, they do not apply to heart rate increases due to physical activity. Also, the heart rates should not be taken as concrete numbers. As always when we are dealing with people there is individual variation.
The "WHITE" zone is the level of anxiety and ability that we experience during our typical resting mode. We progress from "WHITE" to "YELLOW" as our heart rate begins to climb towards 115BPM. As your heart rate nears 120BPM you enter the "RED" Zone, where a loss of fine motor control begins to occur. Entering the "GREY" zone we are moving into a "panic" mode: cognitive ability, vision and auditory senses are all degrading quickly. If the heart rate exceeds 175BPM the psyche and the body essentially, "give up", and either flee or are unable to react.
The firefighter works in an environment where he may face an increase in his heart rate from both exertion and from anxiety. There is no conclusive study that has analyzed the effects of combining the effects of heart rate increase from exertion and a sudden increase in heart rate due to SNS stimulation. It is reasonable to expect that a experienced firefighter who is conducting interior operations, working on his first or second air-bottle will have his heart rate somewhere around the 160 to 180 beat-per-minute range. He will not likely be experiencing any significant psychological challenges, or a loss of cognitive function that impairs his ability to maintain his situation awareness. However if conditions suddenly and unexpectedly deteriorate, he may rapidly go from being calm and collected in the "Yellow Zone" to the "Black Zone" with out any warning.
There is some research we can examine though that can give us an insight into what happens when firefighters become disoriented. The Firefighter Disorientation Study examines the role that disorientation plays in firefighter fatalities. In 100 percent of the cases studied conditions changed suddenly from manageable for aggressive interior operations to prolonged periods of zero visibility conditions. We can expect that those rapid changes would bring about an understandable anxiety reaction. A flood of adrenaline, a quick shift from feeling in control of the situation to being overwhelmed by the conditions would all lead to the sudden surge of the SNS reaction. Couple that SNS surge with a near maximal heart rate and our firefighter is going to move into the "Black" Zone, and have a nearly overwhelming flight response. The dilemma is that when that flight response kicks in the cognitive function shuts down. Rather than calmly thinking, "I need to get my Company together, and turn us around here to follow this hose line out," the survival brain centers kick in and we will only do what we have practiced before. It we've never trained on what to do to maintain Company Integrity and maintain Situational Awareness under rapidly deteriorating conditions, panic will take over, we will become disoriented and those combined forces will result in us likely becoming a fatality.
Our goal must be to develop a training program and a philosophy that will help us stay in the "Yellow Zone", even under those circumstances where the "normal" fireman would be expected to suddenly jump into the "Grey" or "Black" zones. It requires a personal commitment to understanding yourself, your mind and body, and training yourself and your brothers and sisters to have the will to survive. It means becoming a Fire Service Warrior.
Conquering the Fight or Flight Response
Developing survival skills has received quite a bit of attention from our brother and sister warriors in the Military and Law Enforcement Communities. Like us they can find themselves in a life threatening situation with little or no "warm up time". We have already drawn a comparison between the physical work load of firefighting and that of a Navy SEAL; let's see if we can learn some lessons from their survival skills as well. The SEAL, who is patrolling along the streets of Iraq, or the mountains of Afghanistan, is aware of the possibility of coming under attack; he is operating in condition "Yellow", alert and ready to respond. If he begins to take small arms fire from one or two enemy fighters, he has time to recognize and respond to the threat. He should be able to maintain himself in the "Yellow" zone. However if his patrol is suddenly hit by an Improvised Explosive Device (IEDs), or ambushed by a numerically superior force, the chances are that he could rapidly shift into condition "Grey" or "Black". The way the SEAL prepare for those sudden unexpected life threatening encounters is through Immediate Action Drills (IADs). In the IAD the entire platoon responds immediately by using one of several tactics which have been practiced hundreds of times, until the response becomes automatic. There is no need for the cognitive function to operate at 100 percent, because the response has become conditioned. It gives the SEAL Operator the tools to respond instantly and then get his cognitive reasoning back into the mix.Firefighters can also develop the ability to control the fight or flight response. The majority of training to be a Fire Service Warrior will be discussed in Chapter Four, but the critical skills needed by every individual firefighter will be talked about here.
We have talked about how the sympathetic nervous system controls the "Fight or Flight" response. What we must do is develop the skills to control that response. We must train ourselves to recognize and identify that our body has started to go into panic mode, and have developed a conditioned response that will kick in to regain control of our heart rate before we enter the "Black" zone. Conquering the Fight or Flight response requires conscious effort. You must take the time to train yourself before you go out on a call.
In my opinion the single most important element of conditioning yourself to be able to control your fight or flight response was summed up in the Hitchhiker's Guide to the Galaxy; DON'T PANIC! It may seem like a simple thing, but being conscious of how you are responding to the conditions around you sets the stage for being in control of you SNS responses. If you are not conscious of how you are beginning to respond then it is inevitable that your heart rate is going to begin increasing before you are even aware of it. You will begin to move from condition "Yellow" to "Red" to "Grey" with out even realizing it. Making the effort to stay aware of how your body is responding sets the stage for controlling your SNS responses.
The hard part is how do you develop this kind of skill set? We each come to the kitchen table in the morning with different levels of self awareness. We see it in ourselves and our brothers and sisters. Some folks are aware of everything they say before they say it; others are constantly putting their foot in their mouth. We all know that brother firefighter who when the Company Officer asks him, "What were you thinking?" the response is "Nothing." That person isn't lying. He acted with out making a conscious decision about what he was about to do or say.
To develop the ability to be aware of your responses you need to start off by looking at yourself and asking, "What kind of person am I?" Do you regularly speak with out thinking? Do you hear the question, "What were you thinking," and not have an answer? Or, are you the kind of person who is able to articulate your thought process, whether you were right or wrong? Developing that understanding takes self reflection and honesty. You need to start there. Once you can honestly understand yourself then you can being working on how to control those primal survival responses that spring from the mammalian brain that trigger your SNS responses.
I find the best place to begin is with mental rehearsal. Think about the situations you may find yourself in. Think about what aspects of the job you are strong in, and where you are weak. Every one of us has weaknesses. I hate heights. I am not the kind of fireman who finds rappelling from the top of a water tower fun. So I work on it. I climb ladders every chance I get. I hop up and run around on roofs. I will practice self-survival techniques like window bail-outs just so I can conquer that fear. You need to do the same thing with the situations you may find yourself in. Rehearse what you would do if something goes wrong.
Picture yourself crawling down a hallway with your partner to conduct a primary search of a room immediately adjacent to the fire room. The Engine crew has a line stretched to the top of the stairway and is holding the fire in check, leaving you with enough room to get ahead and conduct your search. You are in the lead. Are you doing a left or right hand search? What tools do you and your partner have with you? Which ones do you have? You get to the bedroom door and just before you turn to enter the room the second bedroom flashes over. What are you going to do? If you haven't gotten blown across the hall what hand do you need to put on the wall to retreat? Where is your partner at now? Who is leading the way out? If smoke conditions have suddenly gotten worse, or you did get blown away from the wall, how can you orient yourself to the way out?
These mental rehearsals are important. First it gets you to think about the fact that things can go wrong. None of us want to think that we can get hurt or killed. We try to protect ourselves psychologically by thinking about how things seem to always work out. Unless you have experienced a firefighter fatality, or been injured on the fire ground, it is perfectly normal to not think about the fact that you could be in a situation that could cost you your life. We need to confront the reality that even if we do everything right, the possibly of everything going to Hell exists in every fire building we enter. The second benefit of the mental rehearsal is it gives you the opportunity to "War Game" your options. Think about the various situations you may find yourself in. Go through every action on the fire ground that you could find yourself having to perform: operating the nozzle, being the back-up guy, forcing the front door, being the pump panel operator, being the turntable operator of the aerial, being assigned to vent the roof. Think about the problems that can come up. What if the engine pressure isn't climbing as you throttle up; how do you fix it? What if four people are hanging out the front of a building calling for help; who do you rescue first?
I think the great many of the guys and gals who their peers look to as being "Kick Ass Firemen" already do this. They may not call it mental rehearsal, or even be aware they are doing it, but they are likely doing it.
The second skill set to develop is the ability to control your breathing. Remember how when you were a kid and excited about something that you could hardly speak? What did you mom or dad say, "Take a deep breath and then tell me what happened?" How rapidly you breath has a direct effect on how rapidly your heart beats. Biofeedback is the art, or science according to some, of consciously altering the responses of your autonomic nervous system by being consciously aware of how your body is responding. Breath control is one aspect of biofeedback that I have found to work for me. By consciously slowing your breathing, by concentrating on breathing in a slow, rhythmic manner you can slow your heart rate.
I use a tactical breathing exercise to control my breathing when I recognize that my heart rate is beginning to elevate because of anxiety. I got this exercise from Lt. Col. Dave Grossman's fine book On Combat, which has been referenced before. When you recognize that you are entering a stressful situation, and anxiety is beginning to kick in take that deep breath that mom talked about to a new level.
- Inhale through your nose for a count of four. (One, two, three, four)
- Hold your breath for a count of four. (One, two, three, four)
- Exhale through your mouth for a count of four. (One, two, three, four)
- Pause for a count of four. (One, two, three, four)
Repeat that series three times. You will feel your heart rate slow. You will feel the anxiety begin to ebb. You will be able to regain control of your SNS functions and give your cognitive ability the time to kick in. I've used this exercise dozens of times in the last several years when things get stressful. Whether it has been getting anxious before an interview, or trying to navigate through a complicated SCBA maze in zero visibility and high heat conditions.
The key is to use the tactical breathing exercise on a regular basis. You need to practice it. You need to put it together with the self awareness and the mental rehearsals so that when you are crawling down that hallway an conditions suddenly change you don't freak out, curl up in a ball and get ready to die. You will have the skills in place and the mental attitude to fight, and survive.
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