Fire Safety Science Digital Archive

The investigations reported here show that the production of a foam blanket on the surface of' petrol in a large tank is practicable, and that extinction is possible, by the injection of foam at the bottom of' the tank. The foam produced from many compounds is considerably contaminated with petrol on its way to the surface and although the fire can always be greatly reduced in intensity the burning of the petrol contained in the foam may prevent extinction. Extinction was possible with one particular foam compound, not at the moment in general use, by using it in a 3 per cent solution to produce a foam of low expansion and low critical shearing stress but at the same time with a low rate of drainage. The production of such a foam by any self-aspirating type of equipment would probably not be possible, and the development or modification of a foam pump might well be required. Some suggestions are made of the limiting requirements for practical installations, with the reservation that the figures given should be confirmed by tests on a much larger scale.