Abstract: A method of producing a gaseous, hydrogen peroxide-containing sterilization fluid displaying good, uniform sterilization properties is disclosed. The method includes vaporizing liquefied hydrogen peroxide by injecting the liquefied hydrogen peroxide intermittently in finely-divided form into an air current which serves as a vaporization agent, wherein the air current is kept at a constant or insignificantly varying elevated vaporization temperature. An even vaporization temperature of the air current is ensured because the air, prior to vaporization, is heated by heat exchange with a heating element having a large mass or thermal capacity and a large heat exchange surface area which is kept at the desired elevated temperature by regulated energy supplied to the heating element. During breaks in vaporization between the intermittent injection of the liquefied hydrogen peroxide, the heat exchange surface area is heated with the aid of heat stored in the heating element.