A new generation of "snake oil" fire foam products
I learned early on in my career to stay away from these so called tests.
The worst thing a supplier of products that need to perform could do was let his customers believe that these results really meant something. The pretender foam supplier would claim his product worked as well as real perfromers. At the end of such a test, victory would be proclaimed with ‘high fives for all, free hot dogs, beer and baseball caps if you were a big enough target, (ie., customer, sucker or easy mark). This is a really bad and dangerous deal when lives are on the line! Unfortunately, I’ve been present when the use of a ‘foam pretender’ has gotten firefighters hurt.
If you’re old enough, and I am, you remember the protein foam era. In the 1930’s, the U.S. Navy conducted research for a product that could extinguish flammable liquid fires. The result was a foam liquid that many sailors referred to as ‘Bean Soup’. It is still used in many parts of the world especially when price dictates what is purchased. Composed of a lot of stuff that used to be alive, now dead and ground into small particle like powder. When suspended in water, the liquid concentrate can be proportioned and aspirated to produce finished foam. It was the best product we had when we had nothing else.
Enter fluoro-protein, a great improvement in some areas like performance, shelf life, etc. Viewed from the firefighter’s perspective, it still contained severe limitations including:
Delivery hardware must be of the air aspirating type. The energy lost in this process results in reduced stream reach requiring firefighters to get closer to begin application.
Not allowing firefighters to use nozzles that can quickly switch to a wide fog pattern for personnel protection when things go wrong. Aspirating nozzles don’t have a true wide-fog setting for this action. When in close to a fire, a second hoseline should be in operation for protection for those applying foam when there is any chance of reflash. This, of course, increases manpower requirements for the task.
Many versions were not dry chemical (especially PKP or Purple K) compatible for use on three-dimensional fires.
Entering a pooled fuel for any reason could prove deadly, and did, at more than one large fire.
Oh, and one last thing, it contained some of the F chemical nasty that will be discussed later.
After leaving the municipal fire service in 1972, I joined the industrial fire service and have been in that arena in one capacity or another ever since. Fortunately for me, I was lucky enough to be in on the ground floor of the AFFF (Aqueous Film Forming Foam) era. Regardless of the capacity of my employment (emergency responder, design engineer, sales manager, trainer), when it came to foam, I could always be completely honest with those with whom I dealt. I could not recommend a product that I wouldn’t use myself and that meant high quality AFFF’s and AR-AFFF’s.
With high quality AFFF type products, rapid knockdown is achieved by applying foam bubbles to the liquid surface which is aided by an invisible film secretion (release) that suppresses vapors far ahead of the ‘bubble reservoir’. This film is continuously replenished as long as the bubble pattern contains foam solution. Protein foam advocates still bleated that long lasting blankets, available with protein, were not possible with AFFF. Most of that silliness went away when ‘apples vs. apples’ tests were conducted. Good AFFF’s when applied through air aspirating devices greatly reduce the gap in drain time which, for some diehards, determines the value of a foam blanket. With the invention of AR-AFFF, a gum was added that increased drain time even more often surpassing proteins and allowed foams to be used on both hydrocarbons and polar solvents. This major improvement now allowed a response agency only needed to carry one foam concentrate for virtually any flammable liquid fire. For the remainder of my rant, to conserve space, I will use the term AFFF for both types of concentrate.
In any discussion of foam, the END GOAL must play a prominent role. With AFFF, the END GOAL of a foam response could finally be accurately defined. Many have long believed that extinguishment is the END GOAL, which of course, it is not. Also, no longer was extinguishment defined simply by being present and applying foam when the fire consumed its fuel load unless that was part of the plan. With all of this in mind, I found it necessary to define what I consider to be the END GOAL: “The timely and effective restoration of normal conditions within the limits of acceptable risk”. Notice the absence of the word extinguishment. While this definition covers everything from earthquake, floods, terrorist attacks, oil spills, etc., this article is focused on the END GOAL at flammable liquid fires.
Using this definition, we in the fire service could expand our horizons on just what can be accomplished using AFFF. Such new strategies and tactics include:
Effective application of foam streams from greater distances than ever before, thus increasing safety to the firefighter. The accepted shorter life of foam blankets are greatly offset by ability to accomplish more fire extinguishment while using less foam concentrate. Post extinguishment reapplication periods can be extended by changing to aspirating delivery devices that produce higher quality and longer lasting blankets.
For the first time in flammable liquid firefighting, entering pooled fuel could be considered. In keeping with what I consider the end goal of a response, this should be attempted only if it is considered with the limits of acceptable risk. Rapid film formation and the re-healing (a hold-over term from my days at 3M and ‘Light Water’) of foam blankets dramatically reduces the rate of vapor emissions. In any case, these tactics should only be performed by those competent in the application of these tactics.
If memory serves, the final acceptance test for the U.S. Navy was conducted at what was then Miramar Naval (now an MCAS) Base in San Diego. I still use the video produced to show that appropriately attired ARFF crews and attack lines could be advanced during application for firefighting/simulated rescue efforts into the fully involved test fire. The fuel load was the equivalent of a full load of JP4 for the largest military aircraft in service at the time. Within seconds of the simulated arrival at the scene, firefighters had advanced handlines well into the liquid fire and were nearing the fuselage of the mock up training prop.
It didn’t take long for municipal fire service (including my old FD) to embrace this new technology. The industrial fire responders followed suit years later. They had been convinced that to put out a tank fire you needed a ‘foam with guts’. Their stand was, ‘show us a case history where AFFF has successfully extinguished a fire and we’ll convert’ In 1984, we did and one by one, virtually every refinery and most chemical plants has converted to either AFFF orAR-AFFF. When used correctly by properly trained responders, high quality AFFF’s have never failed to extinguish or otherwise ‘safe’ a scene involving flammable or combustible liquids. Large inventories were considered money in the bank due to the long shelf life of concentrates when stored properly.
Life was pretty good as far as flammable liquid response was concerned and the response community focused on other problems. So, when they came for the halons with an argument that the nasties contained in the most effective gaseous extinguishing agent in the world was destroying the ozone layer above the earth and we were all going to die soon, we said “Tsk-tsk, isn’t that a shame” and moved on. While it was never proven by real scientists (consensus of opinion does not a fact make) the elders of the ‘Church of the Earth’ convinced enough people that we couldn’t take that chance.
We thought we were OK, that they would never come for us. For too long a period, we have maintained the illusion that these well-meaning but misguided folks would never put human life in front of trees. We felt that, once educated, they would understand that to deprive the fire service of the most effective weapon against liquid fires will bring injury and/or death to both firefighters and those they have taken an oath to protect. Unfortunately, their response appears to be ‘trees before people’. You see, the ingredient in AFFF that makes it the most effective foam available comes from that same ‘family of nasties’ known as fluorine.
Some reading this article will say that I’m getting way ahead of myself, that there’s no real evidence this will ever happen and I’m over reacting. Others say that the options are to let it burn, use fluorine free foam or C6 agents. Unfortunately, C6 AFFF foams, while very effective, still contain the nasty stuff. The crusade against AFFF is just getting up a head of steam. The weapon being brandished of late is ‘fluorine free foam’. Some even claim that the foam blanket is self-healing. To that, I say OK, how does it perform? The answer is, so far, not so good….in fact, not good at all.
I am at the end of a very long career in the profession I love and no longer respond to fires in anger. However, I cannot remain silent while we let this happen. For me it’s personal. My son is the fire chief of a major U.S. oil refinery. One of my grandsons is presently considering following in the family tradition of joining the fire service and yet another is in training to become a Damage Controlman in our Navy.
If science can produce a suitable replacement for the high quality fluorine based concentrates in use today, I’m all for it as long as performance is not sacrificed in the process. If we are forced into using one of the presently available F3 fluorine free foams (and my company makes one), a lot of how the fire service handles the threat of flammable and combustible liquids must change. Just some of the changes include: Entering a pooled liquid spill or fire to make victim rescue or close flowing/spraying valves should be considered beyond the limits of ‘acceptable risk’. This alone will require a complete overhaul of how we train. The old term of ‘surround and drown’ and the newer term of ‘hard from the yard’ will guide the development of new tactics.
A possible return to the requirement of using aspirating equipment for foam delivery. This means more energy consumption (water pressure drop), shorter reach, different tactics, additional manpower requirements, etc.
Foam inventories will skyrocket along with all of the related logistical requirements. AFFF’s, because of their effectiveness, were considered up-to-the-task as storage tanks and other hazards continued to increase in size. Add to this, the volatility of some of the newer exotic fuels.
The response community has been disregarding NFPA minimums for many years when hazard size warrants. Without AFFF’s, rates will have to be increased again but this time by some yet to be determined exponential. This, of course, assumes that with greatly increased delivery capacity and sufficient inventories, success (defined as the END GOAL) is possible.
The development of a ‘compatibility criteria’ for dealing with greatly varying concentrate viscosities. Will the hardware required be available to all (mutual aid, etc.) who might be forced to use the concentrate. If not truly compatible, will the result be loss of performance that impact firefighter safety. We have been spoiled with AFFF’s nearly indefinite shelf-life. We are presently comfortable with the ease of handling, wide temperature range for accurate proportioning.
Approval of any AFFF replacement must include discussion of the impact the new concentrate will have on the environment. Most Fluorine Free foams are many times higher in Aquatic toxicity than C6 AFFF’s that contain the nasty stuff that doesn’t easily break down. The new C6 AFFF family, the chemical experts say, are much safer to use but, I’ll stick to firefighting. All this presumes that the products now available can overcome their proportioning and handling issues.
This new ‘pretender’ won’t be easy to relegate to the ‘snake oil’ type of products that we’ve been avoiding for decades. This time we have to overcome ‘big brother, the greenies and tree huggers’. So far, we haven’t had much success shining the light of common sense on the real issues. If we give the benefit of the doubt when it comes to real motive here, maybe it is simply ignorance on the part of those who want AFFF’s to go away … maybe. When they are made aware of the totality of the results they desire, maybe they will come to their senses…….maybe. I am hopeful that my ‘sky is falling’ prognostication never comes to pass. Fire safety may be about to take a huge leap backwards. True fire pioneers and experts that have the funds and resources to vet major changes need to be in place and speak up soon. The first step is to acknowledge that it could happen. Trust me, I don’t want to be right on this one. C