GB1126027A - Fire extinguishers - Google Patents

Abstract

1,126,027. Fire extinguishers. PYRENE CO. Ltd. 10 April, 1967 [17 Feb., 1966], No. 7062/66. Heading A5A. A fire extinguisher of improved extinguishing capacity comprises a pressure vessel 1 charged with an aqueous solution of a perfluoro surface-active agent 16 under gas pressure, a foam improver contained in diptube 6, an outlet valve, and a gas tube 14 terminating in fitting 9 at the base of tube 6 so that when the outlet valve is opened the liquid and gas in the vessel pass out together through the foam improver and the outlet valve. The foam improver may consist of a packed mass of eyelets or hessing rings. In a modification the foam improver is outside the vessel and on the discharge side of the outlet valve. The gas is air or nitrogen under, for example, 200 p.s.i. pressure. The gas tube may contain a valve so that the extinguisher may eject liquid alone. Suitable perfluoro surface-active agents are [C 7 H 15 CONH(CH 2 ) 3 N<SP>+</SP>(CH 3 ) 3 ]I<SP>-</SP>, [C 8 F 17 SO 2 NH(CH 2 ) 3 N<SP>+</SP>(CH 3 ) 3 ]I<SP>-</SP>, [C 7 F 15 CONH (CH 2 ) 3 N<SP>+</SP>(CH 3 ) 2 CH 2 CH 2 OCOCH=CH 2 ]Cl<SP>-</SP>, C 7 F 15 CONH(CH 2 ) 3 N<SP>+</SP>(CH 3 ) 2 CH 2 CH 2 COO- and/or C 8 H 17 SO 2 N C 2 H 5 CH 2 COO<SP>-</SP>K<SP>+</SP>, in 0.1-10% by volume aqueous solution. To obtain a low freezing-point up to 25% volume/ volume ethylene glycol or up to 40% weight/ volume urea may be added to the solution.