OccupantShieldTM
OccupantShield is a self-contained foaming fire suppression system that is designed to mitigate the potential for thermal injury of occupants trapped for extended durations in an enclosed environment such as the vehicle cab of the Marines’ MTVR. Large scale fire testing was conducted at The Massachusetts Firefighting Academy at Stow to evaluate the performance of the foaming fire suppression system. A 100 cubic foot steel box was placed directly next to a propane-fueled pool fire to simulate the cabin of an MTVR vehicle exposed to an external fire. Our prototype successfully delivers over 135 cubic feet of foam in roughly 60 seconds. Several days of testing were used to evaluate the performance of the foaming fire suppression system, both to evaluate the foaming performance itself and to evaluate the effectiveness of the foam in protecting the cabin interior from thermal damage. The foam production system performed as well as in laboratory testing, producing a sufficient volume of foam to fill the test box.
The foam was successful in reducing the risk of thermal injury in the cab. In fire testing producing a heat flux inside the cab similar to the MTVR tests, the foam reduced the total heat flux dose measured at the cabin center during the five minute window after foam deployment by a factor of 4, reducing it from burn injury to non-injury levels. The temperature measured in the cabin in the same testing was reduced by roughly 30 degrees Celsius from the baseline temperature. The hottest spot measured on the cabin walls was quenched from 400 degrees to 100 degrees for roughly 100 seconds during the foam deployment. Overall, the foam cooled the test cab as measured by temperature sensors and insulated the contents of the test cab as measured by the heat flux gauge placed in the cab. See figures below.
Thermocouple tree temperature profiles for both baseline and foam deployment testing from High Fire test.
Vatell heat flux data from foam discharge test of High Fire test.