An apparatus for generating superheated steam capable of reducing or eliminating microorganisms associated with an item includes a gas heater for heating a gas, a steam generator coupled to the gas heater and having a reservoir for supplying water, wherein the heater heats the gas such that when water is combined therewith, a mixture of superheated steam and gas capable of reducing or eliminating microorganisms is discharged from the apparatus. The generation of the steam-gas mixture may be done at one atmosphere of pressure and the mixing may be done prior to expelling the fluid from the apparatus. The apparatus may be configured as a hand-held device, A method of treating an item for microorganisms includes generating a superheated steam at approximately one atmosphere of pressure, directing a flow of the steam onto the item, and reducing or eliminating microorganisms using the steam.
