Cold Compressed Air Foam Fire Suppression Systems Provide Numerous Benefits
Hydraulic systems on logging equipment are subject to a great deal of vibration, chafing, and high temperatures. These conditions cause hydraulic line failures, spilling or leaking flammable hydraulic oil that ignites when it contacts the turbo-charger or exhaust manifold. The resulting engine fires damage and destroy equipment, can injure or kill personnel, cause down time and lost revenue, and can spread and become forest fires.
Dave Mahrt, owner of Kingsway Sales & Marketing in Redding, Calif., has designed a cold Compressed Air Foam (CAF) fire suppression system that significantly reduces the potential for an uncontrollable hydraulic oil fire. Dave has been selling his Tri-Max CAF systems for nearly 10 years to the timber industry. Forest products companies and the U.S. Forest Service have fully incorporated this technology into their operations.
Dave recently developed the Tri-Max AUTO CAF system, which automatically detects and suppresses an onboard engine or hydraulic compartment fire. He has taken the system a step further by adding a 100-foot section of 1-inch collapsible fire hose. The hose enables the system to be used to fight a forest fire sparked by the operation of a hot saw, brush clearing machine, or other cause. The combination effectively turns a timber harvesting machine into a 400-600 gallon CAF ‘fire truck.’
Before getting into the details of how CAF technology works, it’s helpful to know a little about the man who invented it. Dave, a former U.S. Army aviation warrant officer, was a helicopter pilot during the Viet Nam era. “The practice then, and still is, was hot refueling,” he recalled, “which means that the aircraft would be rearmed and refueled while running. Several times the fuel caught fire, heavily damaging or destroying the aircraft and sometimes leading to serious injury or death for the crews. When I saw this happening, I wanted to do something about it.”
The fire extinguishers used then, Dave said, were woefully inadequate to combat the vapors from the flammable fuel. The extinguishers did not reach very far, did not create a ‘blanket’ to prevent air from getting to the fire, and had no vapor sealing capability.
Since the refueling personnel did not wear protective, heat-resistant clothing, they could not get close enough to the fire to be within effective shooting range of the extinguishers, about 10 feet. The heat drove them away, and they were unable to rescue the flight crews.
Innovative solutions to seemingly intractable problems usually are not developed overnight. It took many years for Dave to evolve his technology. During much of this period, over 20 years, he worked as a contract fire-fighting helicopter operator for the Forest Service. He saw firsthand the dangers of fire and the inadequacy of the technology used to combat it.
Dave perfected his fire suppression system and went into business, selling first to the military and then to the Forest Service and timber companies. He has sold over 6,000 systems world-wide.
Dave wanted to be very careful to give the credit for all the technology and all the success for his company to His Lord and Savior, Jesus Christ. “He’s seen me safely through over 400 combat missions in Viet Nam and then over 20 seasons of crop dusting and firefighting with helicopters and airplanes. I consider myself to be a very blessed man. Kingsway is a family business and nearly all my children work in our business. My son, James, heads up our military overhaul and upgrade program, his wife, Shairty, is our office manager, and my son-in-law, Aaron Womack, works with our shop foreman, Leonard Perkins, in the Tri-Max AUTO CAF division and manufacturing the Tri-Max 3 MINI CAF systems. All our family loves the Lord.”
The effectiveness of the Tri-Max technology was dramatically demonstrated in an incident at the U.S. Army National Training Center at Barstow Dagget Airport, Calif. Two Tri-Max 30 wheeled flight line fire suppression systems put out a fire in an office complex that was attached to several World War II wooden hangars; the hangars house the training center’s aviation maintenance operations. The office complex was completely gutted by the fire. Two flight crews wheeled the Tri-Max 30 units over 200 feet and used them to suppress the flames and prevent the fire from spreading to the hangars. This gave the maintenance crews in the hangars enough time to move several helicopters away from the flames.
Tri-Max fire suppression systems basically work like this. Air is stored in a container, like a scuba air tank, under 3,000 pounds of pressure. An industrial regulator takes down the pressure as it enters the system to 150 pounds. A second air line comes from the regulator — and this is where Dave’s patent is at — and goes into an expansion manifold where the CAF foam is generated, expanded and accelerated. As the solution comes out of the liquid tank, the cold air pressure from the scuba air bottles ‘supercharges’ the foam stream. It goes through the hose, expelled a distance of 75-80 feet. Normally a large fire truck would be required to provide this much fire-fighting capability.
“This performance provides a crucial stand-off distance and the necessary discharge range to reach the fire while protecting personnel and equipment,” Dave said. The system is very operator friendly. When the air bottle valve is opened, the system is ready to discharge foam.
The Tri-Max system uses a small quantity of chemical, 3%-6% foam concentrate, mixed with a larger quantity of water for an expansion ratio of 15-20 to 1. On the Tri-Max 20, the 20 gallons of solution converts to 400 gallons of fire suppressing foam; the larger Tri-Max 30 generates about 600 gallons of finished foam. Unlike systems that rely on conventional compressed air, the Tri-Max system has no motors, pumps or moving parts; stored compressed air does not require an air compressor.
The fire-fighting foam blankets an area quickly. The foam smothers the fire and provides a protective cover; it cools the area and also prevents air from reaching the fuel to re-ignite the fire. The foam is formed of small, uniform air bubbles that are very durable. Depending on the temperature, the thick foam blanket can remain for long periods of time without the need for replenishment. For fuel and chemical spills, the foam cover seals flammable vapors to prevent ignition and can contain the spill for hazmat clean-up with little or no water run-off.
The Tri-Max foam adheres to the fuel surface and resists heat longer than ordinary foams. In confined areas, only a small percentage of foam is converted to steam as it travels through the fire to the fuel, which improves visibility. For class A fires, the penetrating foam stops combustion. The result is less smoke and water damage.
“Since this foam is cold, often close to freezing, it absorbs heat faster, thus reducing temperatures to further improve the fire-fighting environment,” Dave said. “Mechanical air compressors produce hot air. Stored compressed air comes out of the air bottles very cold.” The foam even clings to vertical surfaces, he noted, providing superior exposure protection.
Conventional fire extinguishers are effective at a range of about 6-8 feet, Dave noted. Since they discharge a volume of chemical under pressure, they tend to fan the flames, making the fire larger if shot beyond the effective extinguishing range.
By contrast, the cold compressed air foam is effective at a much greater distance, quickly snuffs out the fire, and eliminates any chance of it spreading.
A fire truck can shoot water though a hose at a rate of about 100 gallons per minute, according to Dave, Tri-Max systems can expel about 400-600 gallons of finished foam in less than two minutes. “It’s not how long you fight a fire,” said Dave, “but how quickly you can overwhelm it.”
In addition, water, unlike foam, does not seal off flammable vapors, he added. “Foam is much better on logging industry equipment,” he said, and related machinery, such as chippers and hot saws.
In 1996 the Army replaced halon and 150-pound dry chemical fire suppression systems at aviation facilities with Tri-Max systems. Halon is a chemical gas that has an effective shooting range of about 20 feet — less on a windy day, according to Dave, and creates no foam blanket; the chemical is expelled in a gaseous cloud that vaporizes and dissipates. The Tri-Max CAF system is in every Army aviation facility world-wide, including over 600 systems in combat zones. Tri-Max systems also are used by the Navy, Marines and Air Force as well as U.S. Customs and Border Patrol, many police helicopter operations, and civilian fire departments.
After starting his marketing efforts to the military, Dave turned his efforts to the forest products industry. All U.S. Forest Service and Bureau of Land Management fire-fighting helicopter operations in the West are equipped with Tri-Max systems. Other timber industry companies, such as Sierra Pacific Industries, Weyerhaeuser, John Wheeler Logging, and Warner Enterprises, also use Tri-Max equipment. One of Dave’s biggest clients is Columbia Helicopter, which has Tri-Max systems in all its aircraft and its ground support facilities.
Dave is increasing his efforts to promote his company’s systems to the forest products industry. When asked if Tri-Max fire extinguishing systems were suitable for small contractors, he said, “The independent logger, with just two to three machines, needs them just as much — if not more — than the big companies. Big companies have replacement equipment. If you have only one or two machines and one gets damaged or destroyed by fire, that might put you out of business. The small contractor has more to lose.”
Tri-Max CAF units can be purchased as a self-contained system mounted in the back of a pick-up truck or service truck. The newest Tri-Max AUTO CAF systems mount directly onto logging machines and other equipment, effectively turning them into initial attack vehicles.
Another vitally important benefit of investing in Tri-Max fire suppression systems, noted Dave, is that they can extend work time when logging on federal lands. The Forest Service requires loggers to cease hot saw operations from 1 p.m. to sunset on hot days in certain areas, depending on conditions. However, the agency makes an exception for operations equipped with a portable fire suppression system that can extinguish a 20-foot by 20-foot wildland fire within five minutes of discovery. The following equipment meets the requirements:
A.) Compressed Air Foam system with minimum requirements of 20 gallons of stored CAF, 100 feet of 1-inch hose with adjustable 1-inch nozzle, discharge range of 60 feet, and one spare air cylinder.
B.) Portable off-road water supply, not less than 300 gallons with pump and hose and consistent with tank truck requirements.
The Tri-Max 20/30 AUTO CAF System and Tri-Max 30 and SUPER 60 CAF System meet and exceed the above requirements.
“Look at the advantage if you were allowed to work an extra three or four hours a day,” said Dave. “You could pay for the investment of this state-of-the-art fire suppression equipment in the first season.”
Insurance companies have shown an interest in Tri-Max systems, and Dave suggested that in the future loggers may be eligible for reduced insurance premiums if they enhance fire safety with Tri-Max equipment. “Insurance companies in northern California and southern Oregon have approached me and asked if they could share this knowledge with their clients,” said Dave. “They haven’t made any commitments yet about lowering their premiums. But since they can save reimbursing a $400,000 piece of equipment with an investment of about $8,000 into a unit that can prevent a fire, as well as put it out, I believe that in the not too distant future loggers may be able to qualify for lower premiums for having this device.”
Dave has continually worked to refine his technology and make it more useful to the timber industry. The hand-held unit can be carried in a pick-up truck or even on the harvesting machinery itself. Over 100 Tri-Max 3 Mini CAF units and several Tri-Max 30 and 60 skid units are used by forest products companies in California and Oregon.
The new Tri-Max 20/30 AUTO CAF system is designed to detect and quickly suppress a fire in a machine’s engine compartment and hydraulic systems. The technology has no moving parts and does not require electrical power to operate. It detects a fire and quickly smothers the flames with cold compressed air foam.
The foam solution is made primarily from soap, so it does not harm engines, components or wiring and is easy to clean afterward. “You just wash it with water and let it evaporate,” said Dave.
By contrast, fire extinguishing systems that rely on pumps and motors may become unreliable after a few years of service; they may fail to start when needed to fight a fire. If they have not been properly maintained and cared for, they may not work.
In addition, it may not be possible to large truck to an area of a fire. “In the past, if you had a fire, you had to try to get to the water trailer off the log landing and get it up to the hillside where the log harvester is working,” said Dave. “That typically takes a long time, which allows the fire to get a head start. Our unit dramatically reduces the time it takes to attack a fire, and there are no moving parts to maintain. On the manual Tri-Max systems, you just turn on a bottle of air, charge the fire hose, and point and shoot. We have tested our Tri-Max systems and added lengths of fire hose up to 500 feet. Since the foam is made mostly of air and very little water, you can get nearly the same performance in shooting distance with 500 feet of 1-inch wildland hose as you do with a 50-foot length of hose. That means by adding more fire hose to the system, you can go further to locations that are not accessible, such as down in a draw or up a hill.”
Tri-Max systems are designed to perform in all kinds of weather conditions. Over 6,000 units are in use worldwide, and about 4,000 are in use by the U.S. military. The armed services have them in Iraq and Afghanistan, where temperatures can range from over 100 degrees above zero to 35 degrees below zero. Several hundred Tri-Max systems are in use above the Arctic Circle in Alaska. Tri-Max has a foam solution that is guaranteed to perform successfully down to 20 degrees below zero.
One satisfied logging customer that uses Tri-Max equipment is Dan Krusze, safety director for John Wheeler Logging Inc. in Red Bluff, Calif. “They really make life much easier,” John said. “Before, we had to move the big traditional pumpers around to all our operations. Now we don’t have to do that.”
John Wheeler Logging has Tri-Max systems on its logging and chipping jobs. “Our field mechanics and welding crew also like to have them nearby,” said Dan. The technology likely will gain increased acceptance and application in the forest products industry, he suggested. “I just recently was at a conference…and there was a great deal of discussion about cold compressed air foam fire-fighting systems.”
John Wheeler Logging was required to add the fire suppression systems by Sierra Pacific Industries, which contracts for logging services. Sierra Pacific is the fourth largest timber company in the U.S. and the country’s largest private landholder.
“Right now, these Tri-Max systems are required of all the loggers who work for us as company policy,” said Mike Mitzel, a district manager for Sierra Pacific Industries. The policy has been in place about three years. Loggers contracting with Sierra Pacific are equipped with about 100 Tri-Max systems, and Sierra Pacific has its own fire patrol with five or six smaller units. These units successfully suppress several fires a year. “They greatly reduce the risk of a catastrophic fire,” said Mike.