An Evaluation of Total Flooding High Expansion Foam Fire Suppression Systems for Machinery Space Applications

Full-scale fire tests were conducted to identify the fire extinguishing capabilities and limitations of High Expansion Foam Fire Suppression Systems (HEFFSS) in shipboard machinery space applications. A total of 35 tests were conducted in this evaluation utilizing the equipment and foam concentrates from three manufacturers: Ansul, Buckeye and Chemguard. All three systems easily extinguished the pan fires included in this evaluation independent of the type of fuel (heptane or diesel). The differences in the systems' capabilities were observed during the extinguishment of the heptane spray fires that presented a major challenge to the HEFFSS. The difficulty observed in extinguishing spray fires and, conversely, the ease in extinguishing the pan fires, demonstrates that the current high expansion foam test protocol (MSC/Circ. 670) is inadequate for approving HEFFSS for machinery space applications. As a result, it is recommended that HEFFSS be approved using a modified version of the gaseous agent test protocol MSC/Circ. 848, rather than MSC/Circ. 670. Recommendations on how to modify the protocol to account for the differences between high expansion foam and gaseous agent technologies are provided in the report as well as issues requiring further research.
Prepared in collaboration with the U.S. Coast Guard, Research and Development Center, Groton, CT. Performing organization rept. no. R&DC-632. The original document contains color images.