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Existing portable foam extinguishers generate fire-fighting foam at high pressures with the aid of an air aspirating nozzle. This system could encounter several limitations at the point of application such as poor foam quality due to the use of fire contaminated air for foam generation and insufficient momentum to reach the seat of fire. Research has shown that by incorporating compressed air into a portable foam system, the integrated foam system could generate superior quality foam with high momentum when properly installed with the right components. Several studies had been conducted on the extinguishing performance of compressed air foam systems on multiple fire types, both for small and large fires. Compressed air foam systems mitigate exposure of the operator to heat and provides faster knockdown of the fire plume as compared to air-aspirated foam because of its stronger stability and rheology. Since the expansion ratio of the foam can be regulated to combat specific fire types and sizes, compressed air foam systems can be utilized in protecting a variety of equipment of varied sizes. The aim of this study is to investigate the discharge characteristics of a portable compressed air foam at low pressure. For this study, the requirements of NFPA 10 and CAN/ULC-S508 for a new system were used to determine the feasibility of the system. The effect of air pressure on the expansion ratio of the foam was investigated with foam concentrate ranging from 2% to 4% for three different hoses with lengths of 1-m, 2-m and 3-m. Pressure used ranged from 1.72 bar to 5.52 bar. The 3% and 4% solution for the 2-m hose and 3-m hose exhibited similar trend of a rise and fall with pressure by generating fluid foam of medium expansion ratio in the range of 19 to 28. However, the expansion ratio of 3% solution and 4% solution for the 1-m hose increased monotonically with increasing pressure and generated wet foam of low expansion ratio in the range of 8 to 15. While low expansion foam

The rescue service in Luleå took an initiative in 2014 and completed a try-out with CAF-system and A-foam against a liquid fire of kerosene. The use of the CAF system against liquid fires is in great interest because increased use of A-foam could lower the use of film-forming foams that contain harmful fluorinated substances. This would lead to positive effects on the environment.The try-out in 2014 was successful and indicated that CAF-system with A-foam was a good extinguisher. Luleå rescue service began planning more large-scale try-outs, this time against gasoline fires and this study is part of that project. The aim of this study has been to get an idea of the extinguishing capacity of CAF-system and A-Foam. A literature search showed that no tests similar to those envisaged in this project were documented. The empirical study consisted of 12 small- and 2 large-scale experiments. The liquid that were used in the experiment were gasoline. The small-scale experiment followed the SP-Method 2580 and the large-scale experiment where conducted in a 60 m2 large pit. A summary of the small-scale experiment shows that no control over the fire was obtained when the foam was applied by a direct deposition technique. The foam strikes in to the fuel too hard and the blanket of foam broke down faster than new foam was applied. It required a soft deposition technique to control the fire at the small-scale experiment. The first large-scale experiment failed when no correct foam quality was obtained during the try-out. The second try-out started with the use of a traditionally CAF nozzle, which produces wet heavy foam, and no control of the fire was obtained. The foam equipment had to be changed to a medium expansion nozzle before the fire could be controlled. With the medium expansion nozzle the fire was extinguished in about 5 minutes. More expanded foam, which results in smoother application, was needed to control the fire at the large-scale experiment. The application techn, Validerat; 20150924 (global_studentproject_submitter)

The Marine Corps has approved the replacement of the Twin Agent Unit (TAU) with the Compressed Air Foam System-Mobile (CAFS-M) to provide initial response fire protection capabilities. Modifications were performed on the CAFS-M due to issues on the adequacy of the system to meet mission requirements. This test series validated the modifications, reconfirmed the CAFS-M capabilities and determined the radiant heat effects on firefighters while using the system. A series of seven JP-8 pool fires, ranging in size from 2500 to 7800-sq ft, were used to evaluate the 90% control and full extinguishment times. The effects of radiant heat on the firefighter were monitored using a remote telemetry data acquisition system to monitor skin temperature using temperature probes. System operation was evaluated by conducting tests for throw distance, agent duration, agent stream decay, agent flow rate, expansion ratio, 25% drainage time and foam concentration. The CAFS-M controlled and extinguished all fires within the maximum time criteria. The CAFS-M is capable of extinguishing fires twice the minimum requirement using only 25% of its capacity. Skin temperature measurements confirmed that the CAFS-M provided adequate performance to reduce radiant heat exposure and prevent any subsequent burns. System evaluation showed no performance inadequacies., Original contains color plates: All DTIC reproductions will be in black and white.