A method for making surface corona discharge, which produces ozone gas and apparatus for producing the same are disclosed, in which a dielectric spacer/film having a specific capacity C' equal to or more than 200 nanofarad per square meter positioned between the base electrode and the net electrode. Said net electrode is a wire net or a perforated metal or a wire winding having an open area not less than about 70%, and a size of hole D equals to or less than about 0.7V/P, where V is a voltage in kilovolts and P is pressure of an ambient air or an oxygen in atmospheres. Net electrode has radius R of wire or radius of an edge of openings in the perforated metal equal to or more than about 1.6d, where d is the thickness of the said dielectric spacer/film, which is determined by a fundamental formula d=9k/C', where d is in millimeters, C' is in nF/m2, and k is dimensionless dielectric constant k of given material. Under disclosed parameters said surface corona is safe for human contact if said net electrode is grounded. Start voltage Vst of ozone production is determined by experimental formula Vst=0.7+60/C', kV, here C' in nF/m2. The even and high intensity corona surface and high ozone output takes place if the operating voltage is more than about 3Vst. AC power supply is applied to produce ozone gas at "home" voltage 0.7-1.0 kV and produces ozone gas more effectively at 2,5-3.6 kV. A method for disinfection and decontamination of objects by using the direct corona contact and apparatus for making the same is disclosed, in which safe corona surface is placed on said object and is acting by ozone, ultraviolet and ion bombing simultaneously in the unique environment, which takes place inside of the safe corona. A method for ozone disinfection and decontamination and devices for making the same is disclosed, in which said ozone generating element is placed in a closed container/room with or without treated objects and produce a high ozone concentration due to effective ozone dispersion from corona surface without blowing of air/oxygen through said container/room.