Abstract: A thixotropic high internal phase ratio emulsion which is essentially nonflammable is employed as a fire extinguishing agent. In the preferred embodiment the emulsion contains an aqueous internal phase which makes up the major part of the emulsion, usually in excess of 90%, but preferably in excess of 95%, and a minor amount of an external phase which is of low volatility and/or flammability such as a heavy oil and an emulsifying material. Because it is thixotropic and cohesive, it forms a blanket over a fire, and coats adjacent surfaces, preventing the spread of the fire. This composition is particularly useful in fighting forest fires where the emulsion can be dropped or sprayed from aircraft with a minimum loss due to dispersion in air currents.The invention also comprises a fire extinguisher comprising a container containing a high internal phase ratio emulsion and means for expelling said emulsion onto or in the path of a fire.

Abstract: A thixotropic high internal phase ratio emulsion which is essentially nonflammable is employed as a fire extinguishing agent. In the preferred embodiment the emulsion contains an aqueous internal phase which makes up the major part of the emulsion, usually in excess of 90%, but preferably in excess of 95%, and a minor amount of an external phase which is of low volatility and/or flammability such as a heavy oil and an emulsifying material. Because it is thixotropic and cohesive, it forms a blanket over a fire, and coats adjacent surfaces, preventing the spread of the fire. This composition is particularly useful in fighting forest fires where the emulsion can be dropped or sprayed from aircraft with a minimum loss due to dispersion in air currents.