Abstract: A mixture of an active ingredient such as insecticide, fungicide, repellent or the like and a blowing agent is heated with a hot air current produced by a suitable heat source and a fan to thermally decompose the blowing agent and cause the hot air current and the gas resulting from the thermal decomposition to vaporize and diffuse the active ingredient. The mixture is accommodated within a passage formed in a container and the passage is provided therein with a fan for forcing the hot air current therethrough. A fumigating method and an apparatus of this invention ensure very efficient, quick and uniform diffusion of the vapor of the active ingredients and are usable for controlling vermin and other purposes with high safety and great convenience.

Abstract: A mixture of an active ingredient such as insecticide, fungicide, antiseptic or the like and a blowing agent is heated indirectly with a heat evolved by contacting an exothermic substance with water to decompose the blowing agent and to volatilize the active agent. The mixture is accommodated in at least one compartment of a container while the exothermic substance is accommodated in at least one further compartment provided with water supplying means, said compartments being separated from each other by a partition which provides a heat transferring surface.

Abstract: A mixture of an active ingredient and a blowing agent is heated indirectly with a heating element to thermally decompose the blowing agent and to volatilize the active ingredient. The mixture and the heating element are separated from each other by a partition which provides a heat transfer surface.