A method of decontaminating a surface is provided. A surface to propagate electromagnetic surface waves is provided having a frequency in the microwave spectrum between 1 GHz and 1000 GHz. The surface includes a surface-wave medium or the surface-wave medium is laminated on the surface for confining the electromagnetic surface waves to the surface. The surface-wave medium includes a conductive ground plane. A dielectric is provided on the ground plane. A metallic pattern is provided on the dielectric for increasing an inductive reactance of the surface-wave medium. Electromagnetic surface waves are transmitted onto the surface from a surface-wave coupler coupled to the surface for destroying, removing, or neutralizing chemical or biological surface contaminants. The surface contaminants are destroyed, removed, or neutralized with a plasma created by the electromagnetic surface waves or through absorption of the electromagnetic surface waves.