Exhaust Gas Generates Fire Foam
The exhaust gas of the fire apparatus motor is used by Merryweather & Sons, England, to generate fire foam in conjunction with a portable generator termed the “Xaust-Suds” generator.
The device consists of a small electrically driven pump which can be operated from the electric circuit of the motor. The water inlet of the generator has a shut-off valve. A short length of flexible metal tube connects the exhaust gas pipe of the automobile to the gas inlet of the generator.
Water from the hydrant is led into an hour-glass shaped chamber. At the throat, the exhaust gas is mixed with the foam solution injected by a small electrically driven pump. After passing the narrow throat, the mixture of water, exhaust gas and foam solution passes out into the hose in the form of foam. The manufacturers claim that the cost of operating this device is one-tenth that of a generator using powders. The density of the foam can be varied by changing the speed of the electric motor.