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Compressed Air Foam Wins New Generation of Firefighters

People who manufacture and market compressed air foam systems for fire fighting qualify as hardcore true believers. Despite the fire service's slowness in adopting this technology, its supporters stand firm in their unwavering confidence that it will become one of the great innovations in modern fire fighting.

Among the most adamant of the true believers is David Mahrt, developer of Tri-Max "Kold CAF" technology. Crash Rescue Equipment Service Inc. is now sole manufacturer of the Tri-Max product line by special agreement with Mahrt's California-based Kingsway Sales. Like other CAFS units on the market, Tri-Max differs from traditional air aspirated foam systems in that the air is injected into the foam solution under pressure long before it reaches the nozzle.

"You know the commercial that says 'We take things and make them better,'" Mahrt said. "That could be a commercial for us. We take anybody's foam and make it better."

Tri-Max is one of the handful of fire equipment companies poised to take advantage of the anticipated CAFS boom. Save for sticker shock, the problems with the first troubled CAFS units introduced nearly a quarter century ago have been corrected. Using simple-to-operate technology, a CAFS unit produces finer, more water efficient fire foam that adheres to vertical surfaces and can be applied from greater distances. CAFS has been tested by many years use in wildland fire fighting. Now it is finding its way into small town and rural fire departments nationwide. Even a few big city departments have embraced CAFS. New applications in decontamination and hazardous materials remediation are being explored.

Mahrt took his inspiration to develop his own CAFS line from a 1995 incident in which a pilot and gunner aboard an Army Apache helicopter gunship were severely burned when a fuel spill ignited during refueling. For the lack of an effective extinguisher that could reach the burning copter from beyond the flames, a close friend nearly died. Flames consumed the aircraft in only 18 seconds.

"He had third-degree burns over 70 percent of his body," Mahrt said. "It showed in the photos taken that guys were trying to get close enough with their typical dry chemical and CO2 extinguishers and were not even able to reach the edge of the burning aircraft because the heat was so great."

Mahrt, a former Army chopper pilot himself, became familiar with CAFS through his years of providing air support for wildland fire fighting operations. The first pilot to install a patented foam system aboard a giant S58 Sikorsky helicopter, Mahrt was also the first to mount a CAFS unit with a three-inch monitor able to lay more than 1,000 feet of fire line. (As a high-rise fire fighting experiment, Mahrt once operated a three-inch monitor 300 feet in the air fed by two-inch hose trailing to a pumper below.)

Today, the military are Tri-Max's best customers.

"We have probably 3,000 of our systems in service worldwide," Mahrt said. "The majority are in the military. Maybe 700 to 800 are in civilian service. We have outfitted almost the entire U.S. Army aviation organization from regular Army to the reserve Army to the National Guard. I would say that 99 percent of Army aviation is outfitted with Tri-Max."

The technology is even finding its way into industrial emergency response. In October, Tri-Max sold two of its 60-gallon CAFS units to BP/Amoco to protect the helicopter pad on an offshore oil platform near Egypt.


Usually it is advances in municipal and industrial fire fighting that are later applied to wildland fire fighting, not vice versa. CAFS is the big exception. And, according to one firefighter who was there at the inception of modern CAFS, that has been a hinderance in getting it adopted more widely.

"I think tradition has held CAFS back," said Pat Ebarb, former head of forest fire control for the Texas Forest Service. "It wasn't invented for municipal fire fighting. It came from the wildland side, so municipal firefighters think it must not be very good. In retrospect, almost every application in water delivery in wildland fire fighting came from municipal fire. Here we are coming up with a new system that could be adaptable to the municipal and industrial side. They didn't want any part of it."

CAFS is a surprisingly old technology. "The Royal Engineering Handbook (Provisional) on the Use of Foam Fire-fighting Equipment of 1941," published in the United Kingdom, describes in detail a compressed air foam system used to combat fires on floating bridges involving coverings, coatings, insulation and flammable liquid vapor. The U.S. Navy explored the concept in 1947. By using an air compressor that produced pressure equal to the water pump, the Navy found that two agents, foam solution and air, would readily merge at the mix point. The concept was dropped as too complex. The technology to automatically equalize air and water pressures in such a system would not be available for decades to come.

Actually, the incentive behind the first CAFS system introduced in the 1970s had more to do with security than fire fighting, said Mark Cummins of Texas-based Cummins Industries.

"My brother and I were operating a security company," Cummins said. "One job we were bidding on told us we could get a better contract if we could provide a patrol vehicle with a fire fighting system on it. My father was the inventor of the old FireBoss twin agent system. But it was too heavy and didn't fit the patrol vehicle. So I was looking for a more effective foam system and invented this friction compression method of generating foam."

Unfortunately, Cummins' CAFS unit got a cold reception when he tried to interest a major fire apparatus concern.

"They laughed me out of their office," Cummins said. "So then I took it to David White at the Texas A&M Fire School (later to become publisher of Industrial Fire World). 'What do I do with it?' He said 'Man, I can already see the obstacles with trying to replace all those other systems.' But he gave me the one important clue that got all this started -- 'Go see the Texas Forest Service.' They had just had a fatality on a bulldozer fighting a wildfire. They asked me to design a system that would protect the 134 dozers that they had. From that point it just started evolving."

Ebarb was Cummins' initial contact at the TFS. Eventually the two would go into business selling CAFS units.

"The effect of so much product coming out of this small container blew my mind," Ebarb said. "At that time you had a very small pressure vessel. As Cummins was putting on this demo in Lufkin he just kept spraying and spraying. I was thinking 'He must have a hose connected to it someplace that I can't see.'

"We eventually put him on the payroll as a trainer. The compressed air foam unit using an external air compressor was developed in the shop here. We were able to use different foaming agents as the situation required. That gave us a lot more flexibility."

As a tool for fighting wildfire, CAFS was a big step forward. A stream of compressed air foam from a unit portable enough to strap to a firefighter's back could provide an effective firebreak, sans shovel. In a joking comparison to a one-of-a-kind mammoth piece of fire engineering known as the "North Carolina Rain Maker" that combined a water-filled tanker with a propeller sized directional fan, Ebarb dubbed the new device "the Texas Snow Job." Much to his chagrin, the name stuck.

The next step was using it against other types of fires. With cost sharing assistance from TFS, small rural fire departments in Texas were able to invest in CAFS technology early on, Ebarb said. The new equipment met many of these department's special needs.

"CAFS would fight different kinds of fire," Ebarb said. "It would fight grass and brush fires, which accounted for about two-thirds of the fire load in Texas out of those small departments. It was also good for vehicle fires and house fires. We saw a lot of experimentation done by the National Bureau of Standards and some other folks who actually documented its effect on fires that were confined. So we just saw a wide application for this concept."

One problem with the early CAFS systems was finding an acceptable foaming agent. In the days prior to Class A foam, Cummins and Ebarb experimented first with dish detergent, then settled on 'soapskin,' a byproduct of paper milling.

"It was very viscous looking, almost like axle grease," Ebarb said. "It was the lignin that held the cellular structure of wood together. It was a waste product whenever wood is pulped for paper. Paper mills had a time getting rid of it usually. The major drawback was it was such a great foaming agent that you had to use defoamers to be able to handle it at all. And it was so cheap compared to commercial agents available at the time."

Later Ebarb moved on to the U.S. Forest Service, taking charge of fire control in a 20-state quadrant of the northeastern U.S. But the USFS proved resistant to the benefits of CAFS in wildland fire fighting. Other than developing a pamphlet on CAFS research, Ebarb found that interest at that level was limited. However, Canadians wildland firefighters, introduced to CAFS through an international foam task group, soon adapted the technology to dropping Class A foam from airplanes. Ebarb spread the word further by creating his own Northeastern Area Foam Task Group.

"Although the Bureau of Land Management pushed to have it adopted, the U.S. Forest Service was slow to come along," Ebarb said.

With time, CAFS made headway in the wildland fire fighting market. In particular, Cummins proved its effectiveness in actual use during the epic Yellowstone National Park fires in the summer of 1988 that destroyed 1.2 million acres in and surrounding the park. Also on hand at Yellowstone was a company called Odin that would later become closely identified with CAFS. Jim Guse is administrator in charge of sales at Odin, a division of W.S. Darley.

"They were contract firefighters involved in wildland fire fighting," Guse said. "At first they built CAFS units for themselves." Later, when Odin moved into equipment sales, the company became the first to offer a rotary compressor CAFS unit, he said.


By the mid-1980s, CAFS was firmly established as an important tool in wildland fire fighting. However, beyond that, adapting CAFS to municipal or industrial fire fighting progressed little outside Texas. Ebarb said the main problem was that CAFS units were looked upon as something alien by firefighters not primarily concerned with wildfire.

"Basically, the attitude was 'It wasn't invented for structural fire fighting,'" Ebarb said. "Foam manufacturers did not like that we were using a small percentage of their very expensive foam to do as well as or better than some of their applications. As for municipal fire departments, when you've trained all your life with the kind of foaming agents these companies make and along comes a whole new concept, well, it was not very well received."

The required shift in thinking was too much for most departments to absorb, Cummins said.

"It conflicts with the SOP of the firefighters," Cummins said. "The same with the big equipment manufacturers. They design the infrastructure to handle large volumes of water. They design large delivery applications of water. The inefficiency of current foam systems still require tremendous volumes of water.

"They actually suppressed CAFS for years and years. 'We aren't interested in it, we've already got our equipment. Don't confuse us with all this new fangled stuff?' They've treated it like it was a fad. But when L.A. County did their test and quoted that the CAFS foam out performed the aspirated foam in water applications four to one that made a major impact on the fire service and the manufacturers of the big fire trucks."

Other CAFS manufacturers, big and small, complain about the stubborn resistance to CAFS throughout the fire service. Clarence Grady, foaming systems manager for Pierce Manufacturing, is one of them. In 17 years experience with CAFS, Grady has worked for three of the leading companies in the field.

"Particularly in the structure fire realm a lot of people still don't believe it," Grady said. "It's one of those things you have to turn to the guy and say 'Shut up, I was there and I saw it.' So there are a lot of people just now who say 'I've been on a big fire and you can't possibly do that.' The firefighters tend to sit around the table and come up with all the reasons why it won't work, rather than go try it."

Fire service personnel are too often bound by tradition to have an open mind about new technology, said Geary Roberts, president of Arizona-based Pneumax. The company is a division of Waterous Pumps.

"We showed the fire service 10 years ago that CAFS were a more effective way to do the job, but the average firefighter thinks 'We've been doing it this way for 100 years, why should we change?' " Roberts said. "And if you look at new technology in general, they are just slow to change."

However, manufacturers also own up to problems with early equipment that made CAFS difficult to market. Recovering from that bad first impression took a lot of time, said John Breedlove, director of product development for Intelagard in Broomfield, CO.

"I think a lot of the resistance has come first from the fact that for a long time CAFS have been very complex, requiring specialized training in order to operate them and get them to flow properly," Breedlove said.

"There was a lot of manual adjusting necessary as far as getting them to flow properly. I can say in the past few years we have seen a great improvement in this. But there is a view in industry that they were prone to breakdown because of their complexity."

According to Guse, the innovation that made CAFS a great deal easier to operate is the auto balance valve that automatically equalizes pressure. Rather than worry about pressure, the operator's only concern is how wet or dry the foam should be.

"It's an easy technology but there is enough complication to the system where if people don't build it quite right then it just doesn't work real well," Guse said. "That can give people a black eye. Over the years that's what happened. Some of the old systems just weren't easy to operate and maintain. Nowadays the evolution has moved to the point they are."

Texas-based Neel Associates has been selling CAFS units since the mid-1980s based on design literature distributed by the U.S. Forest Service. According to Ludnicky, many of the original CAFS units on the market had major design defects as multifunction fire fighting apparatus.

"A lot of those units had real small water pumps on them, more like 12 and 15 gpm, and if the air compressed foam system didn't work you didn't have much fire fighting ability in terms resorting to straight water," Ludnicky said. The small pumps were far from adequate for foam production as well.

In Canada, The Snuffer Corporation's entrance into the CAFS business was a direct result of customer complaints about how complicated other systems were to operate, said Snuffer's director of engineering Harry Crawley.

"We got into the business as product people, not firefighters," he said. "A customer asked us to design a system that could make compressed air foam but didn't take a Ph.D. to operate. That is a direct quote from about 10 years ago. So our basis of operation is it had to be simple to operate. We have maintained that throughout.

"We tried to reduce the number of steps and make it as easy to use as possible. And we've been pretty successful doing that. And we will put the type of foam our systems make against anybody's in the industry."

Hale is another CAFS manufacturer whose focus has been on simplifying the technology. Dominic Colletti is Hale's foam system product manager.

"There has been an evolution in the market for CAFS hardware, basically on municipal pumpers," he said. "In the 1970s and 1980s we had what I would call first generation hardware which was basically a mix of components that when put together were, at best, difficult to operate, from a pump operator's standpoint. We went to the second generation in the 1990s and have just released a new CAFS unit that I would classify as third generation.

"One key issue for many departments is that CAFS means training their pump operators to use an air compressor and a foam proportioner in addition to the normal fire pump.. You then need to go through three to six more process steps as you operate the pump panel to generate compressed air foam. So what we have done here at Hale is reduce that complexity to a single step by integrating a compressed air foam system onto a pump. All you have to do is engage the pump on the truck, throttle up, and the system is already activated. It automatically delivers what you need. So what we've done is automated the process. This makes CAFS easy to use and viable for the fire service."

A pump operator has a lot of demands on him under stressful fire ground conditions, Colletti said. Throw all this extra stuff at him at 3 a.m. in the morning it gets even more difficult, with more chances of a factor error. Nobody wants additional complications, he said.

Manufacturers also need to acknowledge that there is a steep learning curve with CAFS, Colletti said.

"A fire pump on a municipal pumper might be anything from 1,250 gpm to 3,000 gpm," he said. "That gives you your delivery rate in liquid content for a fire pump. When you talk about CAFS it's something that most departments ordinarily don't have much experience with. What size air compressor do we need? Do we need a 10 cfm (cubic feet per meter), 30 cfm or 200 cfm?"

Al Ozment of U.S. Foam said tremendous growth lies ahead for CAFS based on the strength of the technology itself.

"There was a day when there were only one or two good CAFS units and eight or nine bad ones," Ozment said. "A bad one will give a black eye to the technology as a whole. People who try the CAFS unit and it doesn't work for them or it doesn't perform or it doesn't hold up under the heavy use of the fire service tend to be just a little disenchanted with the technology. But now I think there are enough manufacturers in the industry and the technology is good enough that the growth will be exponential over the next 10 years."

Even though many of the early problems have been resolved, one major hurdle remains for CAFS technology -- cost. With fire departments strapped for cash at the best of time, the extra dollars needed to buy CAFS often gives customers pause, said Grady at Pierce.

"On a triple combination pumper right now if you go from nothing in your water up to the 200 cfm CAFS with the automatic proportioner, it is going to cost you about $31,000 to $32,000," he said. "That's if you get dual foam tanks where you can do A and B. With some other manufacturers the same system might be $38,000 to $40,000."

At Pierce, CAFS accounts for nearly 10 percent of the company's fire apparatus production, Grady said. The market for CAFS is still in "the build-up phase," he said. Pierce is unique in that it is the only fire truck manufacturer to design, build and install its own CAFS units. Other fire truck makers purchase CAFS from a separate manufacturer, meaning an often steep markup on the final price tag.

With that kind of money involved, fire departments are apt to apply a stringent cost to benefit ratio, Grady said.

"Some people buy off and some people do not," he said.


Yet, despite the sticker shock, an increasing number of fire departments are willing to pay up based on the benefits CAFS offers. Guse at Odin said the last five years has seen immense change in the CAFS market. Much of that change stems from renewed interest by smaller rural and municipal fire departments.

"This is a key thing that a lot of people are missing in the bigger departments," Guse said. "The smaller departments that you think would be just too poor and not want to spend the extra $25,000 or so per truck are opting for CAFS-equipped smaller trucks.

"They don't have much money in some respects, so they want the most effective bang for their buck. They say 'Look, I'm not going to buy a $300,000, 10-man pumper because the only time there is enough people to use it is the Fourth of July parade. This is a volunteer department and there are not many people responding during the day. I'm going to put my money in a CAFS unit that puts out the fire quicker, faster and safer for my people.'"

Selling CAFS continues to be an educational process, said Hale's Colletti.

"I think that if you are going to be spending $30,000 to $40,000 for a foam system you best be sure that you understand the value of what you are buying," he said. "If the department does not understand the value of what CAFS can provide there is no way they are going to spend that money. What are the effects on increasing firefighter safety, reducing fire loss and reducing property damage from excess water? You go through all these things and say 'These are the positives.'"

CAFS is coming out of its visionary phase and becoming a practical investment for small and large fire departments, Colletti said.

"The big hurdle that the fire service has in front of it is getting an understanding of how to specify exactly what will work for them under what conditions and then how to tactically use it," he said. "This is very different from what the plain water application tactic are. "So there is this big training and education job that needs to be done on everything from specifications to how to tactically use it."

Beyond its increasing popularity with small fire departments, CAFS is gaining acceptance from major metropolitan firefighters. The Houston, Los Angeles County and Phoenix Fire Departments use CAFS and require that CAFS be purchased with any new fire trucks. Phoenix Fire Chief Alan Brunacini is on record as saying that any pumper purchased without CAFS is already obsolete.

"Pneumax did a great job of getting CAFS going there," said Guse at Odin, a chief competitor. CAFS units sold by Odin to the Los Angeles City Fire Department have been primarily used in brush fires. Outside the U.S., Odin has sold CAFS in Japan, Argentina and Germany. It has entered into an agreement with German fire apparatus maker Schmitz to help them develop a line of CAFS equipment.

The Houston Fire Department is retrofitting 21 of its trucks with Pneumax CAF units. CAFS gained a major foothold in Texas recently with passage of a new state law granting a 11/2 percent discount on a community's ISO rating if the local department is equipped with CAFS.

"The average CAFS pumper in Houston right now has about a 200 cfm compressor on it," Grady said. "It will put out quite a few hand lines, and up to about a two-inch tip on a deckpipe. The use of that size is the most prevalent. That's what we've been working on for years. A 300 to 400 gpm solution flow rate with the CAFS turned on in the turret has knocked down some huge amounts of fire. In Los Angeles County they have 120 cfm compressors on some rigs. They actually put out an overturned gasoline tanker with a 125 cfm compressor and a deck pipe on an engine."

Pneumax, Snuffer and other CAFS makers report that sales to municipal and rural fire department users now exceeds sales for wildland fire fighting.

As for the man who started it all, Cummins continues to be an innovator in the field of CAFS. He hopes to promote it as a tool in biochemical decontamination, such as in homeland defense. His company is pioneering the use of CAFS for hazardous waste remediation, having recently handled the cleanup of a 82,000 gallon gasoline spill in Pearland, TX.

With regard to fire fighting, he is soon going into production of new "industrial sized" units for municipal and military use.

"It's going to be a large air compressor with the concentrate containers already on it," Cummins said. "All you have to do is connect the water source and use it to cool exposures. The fast little response truck is going to carry the chemicals and haz mat tools. It will be first on the scene. When the fire truck with the CAFS unit shows up you have already made all the preparations."


Nothing sells like success. Since the Tri-Max CAFS system has been adopted by the Army to protect its helicopters, not one aircraft has been lost in a refueling accident. Standard operating procedure at more than 100 Army National Guard, Army reserve units and regular Army posts calls for the designated fire watch personnel to be armed with a Tri-Max 30 with a 300 gpm discharge from a one-inch hose at a minimum range of 75 feet.

"If a fuel spill happens he is trained in that first few seconds to start putting a blanket of foam over the aircraft," Mahrt said.

The Marine Corp now flies KC130 refueling aircraft with one 30-gallon Tri-Max unit aboard and four three-gallon Tri-Max units for use when forward area refueling points for military equipment are established. Mahrt has found civilian applications for the technology as well. Like the military, private companies operating heavy lift helicopters often refuel "hot," i.e., without shutting down.

"To my knowledge, our Tri-Max systems have been instrumental in saving two of these large helicopters from fires during refueling operations," Mahrt said.

His research of refueling accidents shows that there is a critical window of as little as 10 seconds between a fuel spill and ignition. Tri-Max gives fire watch personnel an effective extinguishing agent and a delivery system capable of doing its job within those critical few seconds.

"What we did was take them from fire reaction to fire prevention," Mahrt said. "Most fires are preventable but you have to work through the thought process. How do I prevent a fire? How do I train my personnel to think prevention. Now we have a piece of equipment that can actually put down a blanket of protection over a spill and keep it from igniting. This is what we bring to the industry."

As for wildland fire fighting, Tri-Max units can now be found on initial attack helicopters used by the U.S. Forest Service. The Bureau of Land Management and the Bureau of Indian Affairs also uses Tri-Max in its helicopter operations throughout Alaska and the western U.S.

The true believers march forward. So does progress.


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