PURPOSE: To provide a fire extinguish agent being difficult to be blown off by wind, having a capsule coating easy to be broken by the heat of flares and having the same fire extinguishing performance as that of conventional granular fire extinguishing agents in the vicinity of the flare by contracting and coating 0.1-500g of granular fire extinguishing agent with a heat-shrinkable synthetic resin film.

CONSTITUTION: A granular fire extinguishing agent so far widely used can be used as it is for one filled in a capsule. For example, granular ammonium phosphate coated with silicone resin is used for the granular fire extinguishing agent. A film of resin such as polypropylene, polyethylene, polyvinyl chloride, etc., is used for a heat-shrinkable synthetic resin film for containing the granular fire extinguishing agent. To capsule the granular fire extinguishing agent, the resin film is previously molded into a capsule having 10-300 microns of wall thickness and, for example, a cylindrical, spherical or bag-like shape capable containing the granular fire extinguishing agent. The granular fire extinguishing agent is almost fully contained and enclosed in the capsule.