By Philip Paff

In Australia, a great deal of attention is on the past use of aqueous film forming foam (AFFF) containing perfluorinated compounds (PFCs) such as perfluoro-octanoic acid (PFOA) and perfluoro-octane sulfonate (PFOS) by municipal, industrial, and defense force agencies.

The use and effectiveness of these firefighting foams produced from the 1960s to the early 2000s was good; however, the ongoing development of fuel, environmental, and personnel contamination issues saw a reduction and eventual phasing out of AFFF in the early 2000s. AFFF was intended to extinguish hydrocarbon-based flammable and combustible liquid fires (Class B). Firefighter contamination may have occurred during training or periodic vehicle maintenance. You may have seen AFFF use during foam training or demonstrations such as a simulated boat fire or aircraft crash.

These foam concentrates were mostly water and included a mixture of components such as solvents, biocides, corrosion inhibitors, and foaming agents. The added fluorinated surfactants based on PFOA and PFOS displayed the desirable properties of simultaneously being water and fat repellent. This property assisted with foam solution spread, thereby forming a thin layer over the fuel and creating a barrier that minimized evaporation and reduced heat flux from flame to the fuel, which, in turn, canceled out the feedback loop and extinguished the fire.

1 ARFF training exercises from the early 2000s. (Photo by Jed Crosby.)

What are fluorine-based AFFFs and why the concern?

The emerging issue with many of these foams is the potential health hazard posed by the inclusion of fluorinated surfactants - mainly the two compounds of PFOA and PFOS mentioned earlier. Typically, fluorinated foams contained 0.5 to 1.5 percent PFOS and trace quantities of PFOA. Studies have shown that PFOS is a toxic pollutant that remains in the environment indefinitely, with research estimating time frames of 30 to 90 years. PFCs are bio-accumulative, meaning that they can also build up in biological tissue.

PFCs have many applications, from coatings on nonstick cookware to an additive in concrete, and are very pervasive in our environment. Because of widespread applications, PFCs now contaminate every ecosystem on the planet. Being bio-accumulative ensures they enter the food chain; therefore, levels increase as they are consumed by animals such as fish and cattle, progressively being concentrated in the food chain before eventually ending up in humans.

These two materials are environmentally persistent, with a long half-life (it takes approximately 42 years to rid 50 percent of PFOS and 91 years to rid 50 percent of PFOA from the environment). PFOS is classified as a persistent organic pollutant, while PFOA is classified as a Class 2B carcinogen (it is possibly carcinogenic based on limited available evidence).

Impacts

There are two key areas of concern with these AFFFs containing these compounds: environmental impacts and health impacts.

Concerning the health impact, it is important to recognize that the body cannot metabolize these chemicals. Studies show it can take between four and eight years for the body to rid itself of half of any PFOS/PFOA exposure. There is some evidence reported in literature of animal studies of changes in the liver, kidney, thyroid, pancreas, and hormone product

By Philip Paff

In Australia, a great deal of attention is on the past use of aqueous film forming foam (AFFF) containing perfluorinated compounds (PFCs) such as perfluoro-octanoic acid (PFOA) and perfluoro-octane sulfonate (PFOS) by municipal, industrial, and defense force agencies.

The use and effectiveness of these firefighting foams produced from the 1960s to the early 2000s was good; however, the ongoing development of fuel, environmental, and personnel contamination issues saw a reduction and eventual phasing out of AFFF in the early 2000s. AFFF was intended to extinguish hydrocarbon-based flammable and combustible liquid fires (Class B). Firefighter contamination may have occurred during training or periodic vehicle maintenance. You may have seen AFFF use during foam training or demonstrations such as a simulated boat fire or aircraft crash.

These foam concentrates were mostly water and included a mixture of components such as solvents, biocides, corrosion inhibitors, and foaming agents. The added fluorinated surfactants based on PFOA and PFOS displayed the desirable properties of simultaneously being water and fat repellent. This property assisted with foam solution spread, thereby forming a thin layer over the fuel and creating a barrier that minimized evaporation and reduced heat flux from flame to the fuel, which, in turn, canceled out the feedback loop and extinguished the fire.

1 ARFF training exercises from the early 2000s. (Photo by Jed Crosby.)

What are fluorine-based AFFFs and why the concern?

The emerging issue with many of these foams is the potential health hazard posed by the inclusion of fluorinated surfactants - mainly the two compounds of PFOA and PFOS mentioned earlier. Typically, fluorinated foams contained 0.5 to 1.5 percent PFOS and trace quantities of PFOA. Studies have shown that PFOS is a toxic pollutant that remains in the environment indefinitely, with research estimating time frames of 30 to 90 years. PFCs are bio-accumulative, meaning that they can also build up in biological tissue.

PFCs have many applications, from coatings on nonstick cookware to an additive in concrete, and are very pervasive in our environment. Because of widespread applications, PFCs now contaminate every ecosystem on the planet. Being bio-accumulative ensures they enter the food chain; therefore, levels increase as they are consumed by animals such as fish and cattle, progressively being concentrated in the food chain before eventually ending up in humans.

These two materials are environmentally persistent, with a long half-life (it takes approximately 42 years to rid 50 percent of PFOS and 91 years to rid 50 percent of PFOA from the environment). PFOS is classified as a persistent organic pollutant, while PFOA is classified as a Class 2B carcinogen (it is possibly carcinogenic based on limited available evidence).

Impacts

There are two key areas of concern with these AFFFs containing these compounds: environmental impacts and health impacts.

Concerning the health impact, it is important to recognize that the body cannot metabolize these chemicals. Studies show it can take between four and eight years for the body to rid itself of half of any PFOS/PFOA exposure. There is some evidence reported in literature of animal studies of changes in the liver, kidney, thyroid, pancreas, and hormone product

Richard Marinucci

Wildland fires within the wildland urban interface (WUI) are major events that require special training, equipment, and strategies. Many urban and suburban firefighters have no chance of ever responding to these calls.

But, many will go to much smaller grass and brush fires, especially in mid to late summer when rainfall is less frequent. These calls are not especially complex, but complacency can set in and create challenges. It pays to prepare by reviewing basic concepts.

In many firefighters’ response districts, there are few large areas of grass or brush. As a result, departments give little attention to these incidents as they are perceived as more of a nuisance than a threat. In most cases, they are correct. With all the responsibilities that are part of a well-run department, there often is not time to do everything, so there is a prioritization of incidents. But, all organizations should at least briefly review their operations on these calls so that complacency does not set in.

For the most part there are two threats to firefighters when operating on WUI incidents: health-related and roadway-operation-related. You could add a risk to injury in that responders are operating on uneven surfaces and are subject to sprains and strains.

Awareness is important when minimizing risks to firefighters. There always needs to be a sense that something could go wrong in any aspect of this profession. When someone lets his guard down, there is the added potential for a mishap or worse. We must not overlook the simple things.

Roadway Response

Working on the roadway or nearby is a very risky venture for firefighters. Included in the different types of grass fires experienced by departments are small fires along interstate or limited access highways. They look innocent enough and, for the most part, the fire extinguishment aspect is. The fires are easily extinguished - and the grass comes back greener. It is the threat from traffic that must be considered. A firefighter in South Carolina was killed while operating on such an incident when a vehicle went through the site and hit the firefighter. You can get more information on this from the National Institute for Occupational Safety and Health (NIOSH) report. It is a stark reminder that the risks exist, and you cannot ease up even when the fire operation is so simple.

Health-Related Injuries

Health, wellness, and fitness are also factors. Working on brush or grass fires can be hard work depending on the location and what is burning. It may take some effort to get to the fire, especially if a suburban or urban department does not have the off-road capabilities that others may have. This extra work can add stress to the cardiac system. Further adding to this is the fact that many of these events occur during weather extremes - i.e., heat and humidity. And, structural firefighting protective clothing is sometimes the only option for operations. Organizations should be cognizant of the potential for health-related problems and either establish an on-scene rehab (if the incident lasts very long) or closely monitor personnel when they return to the station. This will mean adequately hydrating and monitoring vital signs at the least. Officers and supervisors should be in the habit of making sure that the personnel are evaluated properly and monitored as needed. Again, there are NIOSH reports of firefighters suffering from stress events on calls that are not of the magnitude of the major wildland fires.

Fire App

Richard Marinucci

Wildland fires within the wildland urban interface (WUI) are major events that require special training, equipment, and strategies. Many urban and suburban firefighters have no chance of ever responding to these calls.

But, many will go to much smaller grass and brush fires, especially in mid to late summer when rainfall is less frequent. These calls are not especially complex, but complacency can set in and create challenges. It pays to prepare by reviewing basic concepts.

In many firefighters’ response districts, there are few large areas of grass or brush. As a result, departments give little attention to these incidents as they are perceived as more of a nuisance than a threat. In most cases, they are correct. With all the responsibilities that are part of a well-run department, there often is not time to do everything, so there is a prioritization of incidents. But, all organizations should at least briefly review their operations on these calls so that complacency does not set in.

For the most part there are two threats to firefighters when operating on WUI incidents: health-related and roadway-operation-related. You could add a risk to injury in that responders are operating on uneven surfaces and are subject to sprains and strains.

Awareness is important when minimizing risks to firefighters. There always needs to be a sense that something could go wrong in any aspect of this profession. When someone lets his guard down, there is the added potential for a mishap or worse. We must not overlook the simple things.

Roadway Response

Working on the roadway or nearby is a very risky venture for firefighters. Included in the different types of grass fires experienced by departments are small fires along interstate or limited access highways. They look innocent enough and, for the most part, the fire extinguishment aspect is. The fires are easily extinguished - and the grass comes back greener. It is the threat from traffic that must be considered. A firefighter in South Carolina was killed while operating on such an incident when a vehicle went through the site and hit the firefighter. You can get more information on this from the National Institute for Occupational Safety and Health (NIOSH) report. It is a stark reminder that the risks exist, and you cannot ease up even when the fire operation is so simple.

Health-Related Injuries

Health, wellness, and fitness are also factors. Working on brush or grass fires can be hard work depending on the location and what is burning. It may take some effort to get to the fire, especially if a suburban or urban department does not have the off-road capabilities that others may have. This extra work can add stress to the cardiac system. Further adding to this is the fact that many of these events occur during weather extremes - i.e., heat and humidity. And, structural firefighting protective clothing is sometimes the only option for operations. Organizations should be cognizant of the potential for health-related problems and either establish an on-scene rehab (if the incident lasts very long) or closely monitor personnel when they return to the station. This will mean adequately hydrating and monitoring vital signs at the least. Officers and supervisors should be in the habit of making sure that the personnel are evaluated properly and monitored as needed. Again, there are NIOSH reports of firefighters suffering from stress events on calls that are not of the magnitude of the major wildland fires.

Fire App