Abstract: Fire-fighting foam effecting against burning hydrophilic or polar liquids like lower alcohols, ketones, etc. is made from concentrate containing thixotropic thickener dissolved in large amount, yet has a tolerable viscosity particularly when stirred. Heteropolysaccharide-7 or chain-shortened modifications of it are suitable for this purpose. The concentrate can also be made suitable for fighting fires on hydrophobic liquids by adding surfactants that cause aqueous film formation over such liquids.

Abstract: Aqueous foam formed with a solution containing a thixotropic polysaccharide in addition to foaming agent, will gel when projected onto a burning hydrophilic liquid, and such foam is not destroyed by the liquid, so that it is suitable to fight fires on hydrophilic liquids as well as on hydrophobic liquids and on solids that are compatible with the foam. The thixotropic character enables the ready pumping of the foam and of the solution from which it is formed. A substantial content of N-methyl pyrrolidone-2 in a concentrate for such foam-producing solution makes such concentrate more adaptable for ready dilution and also improves its stability. Other ingredients can also be included such as to form films over hydrophobic liquids to improve the stability of the foam that is formed and to increase the thixotropic action.

Abstract: Aqueous foam formed with solution containing thixotropic polysaccharide in addition to foaming agent, will gel when projected onto a burning hydrophilic liquid, and such foam is not destroyed by the liquid, so that it is suitable to fight fires on hydrophilic liquids as well as on hydrophobic liquids and on solids that are compatible with the foam. The thixotropic character enables the ready pumping of the foam and of the solution from which it is formed. A substantial content of N-methyl pyrrolidone-2 in a concentrate for such foam-producing solution can make such concentrate more adaptable for ready dilution and also improves its stability. Urea can be added to help solubilize the polysaccharide, and it will also reduce the viscosity of a concentrate. Other ingredients can also be included such as to form films over hydrophobic liquids to improve the stability of the foam that is formed and to increase the thixotropic action.

Abstract: Aqueous foam type film-forming fire-fighting composition contains surfactant having fluorocarbon radical and of relatively simple and effective structure but not suitable by itself for use with sea water, combined with a foamability-improving surfactant that is suitable for use with sea water and in an amount that makes the entire composition suitable for use with sea water.

Abstract: Floating tank top pivotally carrying upwardly projecting weather shield plates around its periphery for biasing outwardly against inside surface of tank wall, has bias mechanism arranged to tilt the plates inwardly in response to fire to expose roof seal at site of fire and help direct fire-fighting foam into exposed location.

Abstract: Certain fluorocarbon surfactants combined with certain silicone surfactants provide mixtures that reduce the surface tension of water to 19 dynes or less per centimeter, and when foamed are particularly effective in fighting fires involving lighter-than-water hydrophobic liquids. Mixtures are further improved with certain other surfactants and use less of the fluorocarbon surfactants to provide fire fighting effectiveness of prior art compositions which do not contain silicone surfactants. Hydrophilic resins and sequestering agents can also be contained in the mixtures.

Abstract: Certain fluorocarbon surfactants combined with certain silicone surfactants provide mixtures that reduce the surface tension of water to 19 dynes or less per centimeter, and when foamed are particularly effective in fighting fires involving lighter-than-water hydrophobic liquids. Mixtures are further improved with certain other surfactants and use less of the fluorocarbon surfactants to provide fire fighting effectiveness of prior art compositions which do not contain silicone surfactants. Hydrophilic resins and sequestering agents can also be contained in the mixtures.