By: Paul Juergens – Wyoming State Director (Firefighter Cancer Support Network)
Over the years there have been many advancements in terms of firefighter PPE. These advancements answered specific problems that firefighters face, mostly to protect against thermal injuries and for airway protection. Firefighters identified a problem and when ingenuity or technology provided an answer, safety was enhanced and fireground activities became more effective.
The Nomex Hood
For many years the Nomex Hood has performed the near impossible task of providing a significant amount of thermal protection for firefighter’s neck and head, while providing a great deal of flexibility at the same time. But a problem still present for the everyday firefighter remains to be the occupational cancer risks from products of combustion while wearing the Nomex hood.
According to the IAFF, firefighter cancer is the leading cause of line of duty death in the fire service. From 2002 to 2020, 67% of the names added to the IAFF Memorial Wall in Colorado Springs were occupational cancer fatalities. While there are many studies that show the connection from the carcinogens that are present in soot such as polycyclic aromatic hydrocarbons (PAH), formaldehyde and, chromium and many other toxins, this is a place where light and flexible material is causing some unknown dangers to firefighters.
On January 6, 2015 the IAFF funded a florescent aerosol screening test, performed by RTI to determine the potential spread of soot underneath the PPE of firefighters. The firefighter was dressed in full turnout gear, on air with all protective measures (neck enclosure was fastened and the helmet ear flaps were down), then placed into a room that was filled with the florescent particles, .1 to 10 microns in size to approximate the size of soot particles found in a structure fire. The temp was controlled at 70°F, humidity was 50% and the firefighter did exercises similar to fireground tasks for 30 minutes to simulate activities performed during interior structure fire suppression. The firefighter doffed the gear and was examined with a black light to determine the amount of fluorescents that were able to find its way to the skin surfaces.
The resulting pictures make it clear that a large amount of fluorescents made it to the skin of the firefighter in the neck area penetrating the Nomex hood material. That isn’t to say that it was not present anywhere else on his skin, it was. Other pictures that weren’t included in this article show there is contaminants that make it through the bottom of the pant legs and the top of pants/bottom of the coat interchange.
Firefighters and occupational cancers
Many studies have been done regarding the increased risk to firefighters and occupational cancer, but the general average of all types of cancer studied is that firefighters have a 9% higher chance of developing a cancer, and those firefighters that are diagnosed have a 14% higher mortality rate when compared to the general population with the same type of cancer. The following list contains cancer that appears to have a link to the contamination to a contaminated hood, and the increased risk that firefighters face:
From the pictures, it is easy to see the visual evidence that the fluorescents have on the neck and face area that aren’t covered completely by the mask or coat. Testicular and prostate cancer were not a mistake to make this list, the connection isn’t immediate when a dirty hood is considered. But in my mind there is a connection to these specific cancers and a dirty hood and will be discussed later in this article.
Temperature and exposure risk
Dr. C. Stuart Baxter of the University of Cincinnati has reported a few other findings that shed some more light on the subject. Baxter reports that for every five degrees (Fahrenheit) in the increase of skin temperature there is a 400% greater absorption. Dr. Baxter also looks into the relative permeability of the skin. If the skin at the foot of the arch is given a value of one, the angle of the jaw has a value of 93, the groin area is 300, and thus the groin area has a relative permeability of 300 times greater than the arch of the foot.
Real life applications
Anyone who has been to a fire has seen dirty firefighters exit a structure. Normally there is an exchange of information to an officer, then the crews proceed to the rehabilitation area. In my experience, a few things happen. The firefighters doff the helmet, airpack, mask, gloves and proceed to the rehab area. Unless the weather is especially hot, the hood is simply pulled down around the neck, while the firefighter drinks water, gets a blood pressure taken and is waiting for the next assignment. When one considers the permeability of the Nomex hood to literally allow the neck to be marinating in the toxic cocktail blended with the products of combustion, while maintaining an increased skin temperature, making the hood act like an insulating scarf. It stands to reason that the last thing one wants to happen is to maintain a close contact with a toxin, while increasing the absorption rate at the same time.
Prevention is still key
Fires are dangerous and much more toxic than in the past. But there are steps that can be done to reduce the amount of absorption a firefighter must face, ranging from the very simple to more expensive and complex.
The Value of on scene decon
One of the easiest, cheapest and most effective things that can be done to reduce the absorption of carcinogens is to simply remove them from the firefighter as soon as possible. This begins with a decon procedure. The materials required for conducting a good decon are really quite simple, a bucket of soapy water, a long handled brush, and a garden hose with a nozzle. But the most important asset one can bring to the decon station is a proper understanding of the importance of conducting effective decon and the associated dangers of complacency.
- After exiting the structure and still on air, enter the decon area. The person with the lowest amount of remaining air goes first.
- The firefighter with the most air in the SCBA takes the garden hose and thoroughly rinses off his/her partner with clear water. If there is a great deal of particles clinging to the firefighter (such as overhaul procedures-blown in insulation) a brush can be used prior to water rinse. Take care not to get the inside of the bunker gear (to include the helmet) wet, keep all water directed only at the outer shell rinsing only from the collar line on down.
- Using the brush and soapy water scrub the outer shell of the firefighter.
- Rinse soap off and reverse roles.
- Doff gloves first, avoiding contact with skin with the outside of the glove.
- Remove gloves without touching the outside of the glove with bare hand.
- Doff coat, mask, helmet and hood. Firefighters should hold their breath while removing the dirty hood so not to inhale any contaminants and place hood in a receptacle to be cleaned at the station before being reused.
- Use department issued disposable wipes, starting with hands, face, neck and hair. Use several wipes to avoid spreading the contaminants from on area of the body to another.
- If the firefighter is to reenter the fire scene, don a clean, dry hood.
- Place dirty bunker gear in plastic bags to be cleaned at the station.
It is worth noting that in freezing fire scenes, the water wash/rinse should be replaced with a dry brush. Especially if the fire crews may have to reenter the fire scene. As I live in Wyoming, I have dealt with ice-covered gear in subzero conditions. But studies show that the soap and water wash and rinse removes 85% of toxins from the bunker gear, while the dry brush is only about 25% effective. But in freezing weather, 25% is better than zero. Skeptics may also criticize the value of on scene decon due to the danger of steam burns and the added weight that wet decon will add to the firefighters due to wet gear. According to a study in the state of Florida, wet decon only increases three to four pounds of weight when compared to the dry weight of a firefighter. Additionally, if the decon personnel only apply water to the outer shell, there is no danger of steam burns to fire crews, entering the fire ground/live fire training, immediately after wet decon is performed.
If a person views the toxins in the fireground as a Haz-Mat scene, the above steps make more sense. That is not to say that a structure fire should be treated exactly like a chemical spill, things must happen quickly in most cases to mitigate the hazard, or perform a rescue.
The rise of testicular cancer
Like most firefighters, the threat of testicular cancer demands complete attention. Unlike many other cancers, the tumor (in this case the testicle) is removed then biopsied. For most cancers, the biopsy precedes the surgery. That reason alone should make people sit up and take notice.
Many may be wondering at this point what the connection between a dirty hood and testicular/prostate cancer could be. The following is simply based on my own personal observations that firefighters perform when laying out their gear next to the engine. If one assumes that the hood has not been properly cleaned after a fire, and the permeability and saturation that the hood is capable of possessing, it is easy to see the hood as a medium of cross-contamination.
Most firefighters I have observed tend to lay out their gear in such a way that it can be quickly donned in responding to an emergency. Nearly everyone has their own method of laying out their coat, boots, radio to aid in rapid donning. However many firefighters have a habit of laying the hood between their bunker boots, in the crotch of their pants for easy access.
By no way is this theory a claim to empirical evidence, but logically the hood seems to be a major carrier for the carcinogens that plague firefighters. In this example the increased testicular and prostate cancer rates may have a common cause, as well as an easy way to reduce those risks. The easiest is to clean the hood first before laying it in on your bunker gear. Remember the highly permeability of the groin area is 300 times more permeable than the skin on the arch of the foot. As firefighters we need to do our best not to become our own worst enemy.
Keep your hood clean
In addition to the above decon procedures there are some simple things that can be done specifically about the hood. First of all, change out of a dirty hood at a fire before reentering the IDLH. This means the firefighter has access to multiple hoods. Some departments have a container of clean hoods that are used whenever a member needs a clean hood on a fire scene.
Additionally, advancements have been made concerning the hood design. Some have a barrier or particulate filter incorporated in the fabric of the hood. The intent of this article is not to endorse a style or brand, simply to increase the awareness of the increased protection available.
The Nomex hood idea is a small portion of all of the steps that can be done to reduce the risk of firefighter cancer. Other actions include:
- Clean cab concept
- Improved diet
- Sleep hygiene
- Designating the fire station into hot, warm, and cold zones
- Shower as soon as possible at the station after a fire (shower within the hour)
- Regular exercise
- Stop using tobacco products
- Wear SCBA during overhaul
- Source capture systems in the fire station for diesel exhaust
- Don’t transport contaminated gear in personal vehicle
As with any prevention program, it is difficult to quantify the exact value in terms of statistics that these actions will generate. The 9% higher incident of firefighter cancer when compared to the general population is reason to seriously review what can be done. We owe it to ourselves, to our families and to those firefighters who will follow, to change the culture and attitudes of how we view the toxins present at a modern fire.
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