The discomfort from being woken from an alarm is evident: the sound jolts and jars us out of our highly needed state of restoration, the important sleep most of us lack.
However, discomfort is pale in comparison to the serious physiological consequences of tone systems, which result in hypertensive conditions for the heart, and even sudden cardiac death. Through evolution, the natural way our bodies transition out of deep rest to an awake state is our biological response to light. So how do our bodies respond to tones in the firehouse as a means to alerting a call?
From department to department, I consistently hear members unanimously comment on how tones negatively impact their sleep and overall health. There is research-based evidence that confirms these discussions and proves that tones can be damaging to both heart health and sleep patterns. First, let’s look at how the body and mind respond to sound. Sound consultant, Julian Treasure says that “(certain) sounds affect us physiologically in very powerful ways. Because hearing is your primary warning sense, a sudden sound will start a process. It releases cortisol; it increases your heart rate, it changes your breathing. This is because we’ve been programmed over hundreds of thousands of years to assume that any sudden or unexplained sound is a threat and your body gets ready to fight or flee.” Firefighters already experience heightened levels of stress hormones like cortisol and adrenaline, which compromise heart and sleep health. So why would disruptive tones be used at all in the firehouse? Well, they shouldn’t be.
Noise pollution or, “decibel hell” has direct consequences on firefighter health. The magnitude and loudness of sound is measured in dB (decibels) and has a scale of 0 to 140, with 0 being inaudible and 140 being the maximum threshold for pain, and can be accompanied by instant, permanent hearing loss. Firefighters are commonly exposed to dB levels over 100 with the sounds on scene and in the firehouse. According to a NIOSH Alert on preventing firefighter fatalities, “Noise exposures are obvious: sirens, air horns, diesel engines, and the roar of a large structure fire itself. During emergency operations, sound levels exceeding 120 decibels have been measured. Studies of community and occupational groups have found an association between noise exposure and hypertension, and possibly an association with ischemic heart disease.” In an industry where so many of these noise factors cannot be controlled, why would we voluntarily install and utilize systems that exacerbate the endocrine system, putting firefighters at higher risks to exposures that negatively impact their health? In one study on tones, at times firefighters would have a “resting heart rate of 40 instantly shoot up to 160. These heart rates often remained high throughout the time of the response, call and return to service.” Firefighters already have a fight or flight response due to the disruption of the circadian rhythm; there is no need to heighten this stress response with the jolt of a tone.
I recall discussing with a Denver Firefighter how firefighters are able to respond to calls that are extremely high intensity, and where people on scene may be experiencing overwhelming emotions and stress. He says, “We remember it is not our emergency.” In our busy, unpredictable world it is increasingly crucial for first responders to be able to remain calm and collected on calls for best decision making. But firehouse tones compromises a first responder’s ability to do this. The jarring sound of tones, especially throughout the night, triggers the body to be flooded with stress hormones. This chemical change causes the first responder to enter their own “fight or flight” experience, and while the rational mind recognizes the emergency belongs to the “other,” the body of the first responder is primed for its’ own survival as it is biologically convinced they too are undergoing their own personal emergency. This chronic state of elevated stress hormones in the body is why cardiac events and metabolic disorders take the lives of firefighters every year. So the tones that set off this chemical dump are not only ineffective and unnecessary, they are counteractive to the fundamental job firefighters must do every day, and compromise their health at the same time.
Every sound is cataloged in our memories, and when we hear certain sounds, there is an association that has a parallel emotional and physiological response. This is why off shift, seemingly inconsequential sounds will elicit a physical response if it has an association to the firehouse. Our subconscious sound associations are powerful enough to dictate instant and massive hormone release like adrenaline and cortisol, which will keep us awake at night and give us high blood pressure. So consciously creating associations through sleep hygiene practices, dedicating a designated sleep space, and breathing techniques that focus on lengthening the exhale (as taught in the First Responder Sleep Recovery Program) are critically important in countering these effects.
The other reason alternatives to tones are relevant to health and wellness is how we have evolved to have a slow and steady waking mechanism from sleep, in synchronization with the sunlight as it increases from night to day. Every system in our body depends on the circadian rhythm for healthy function. It regulates our heart function, our immune system, emotional state and our cognitive abilities. Having progressive light signals in the firehouse over the course of a couple of seconds is an optimal way to wake for a call. Progressive lights would have less fight or flight hormone dumps on the body than to abrupt tones. An example of this alarm indicator would be a progressive light system that starts with red, changes to orange, and finally switches to yellow light.
These colors are the least disruptive to the circadian rhythm but would suffice to alert and wake up somebody from sleep. This type of system would be more beneficial to waking in the firehouse. This subtle change could save the heart and sleep health of firefighters nationwide. According to the U.S. Fire Administration, “Small but significant decreases in the amount of tachycardia response to station alerting can be achieved with simple alterations in alerting methods.”
Here is the call to action- it is time for fire departments and administrations nationwide to take ownership over their members’ health and wellness. We are in 2018, time to take steps to mitigate the factors in the firehouse contributing to sudden cardiac death. Sound off, silent alarm on, and firefighters can respond with healthy hearts and go back to sleep more easily after a call.
Treasure, Julian. The Four Ways Sound Affects Us. https://www.juliantreasure.com/blog/4-ways-sound-affects/
NIOSH Alert. Preventing Fire Fighter Fatalities Due to Heart Attacks and Other Sudden Cardiovascular Events. https://www.cdc.gov/niosh/docs/2007-133/pdfs/2007-133.pdf
The Effect of Alerting and Tones on Firefighters’ Heart Rates https://www.usfa.fema.gov/current_events/071317.html