FIELD: fire-fighting technique. SUBSTANCE: supplied to free volume of storage tank is gas inert mixture by jets uniformly distributed over circumference and parallel to storage tank roof. In this case, consumption of gas inert mixture is taken on the basis of absence of mixing of layers of gas inert mixture and layer of vapors of oil products. In case of pressure in free volume of storage tank exceeding the preset value, vapor-gas mixture is released through gas-holder whose volume is not less than amplitude of volume variation of oil product in storage tank. Gas inert mixture is used in form of dry air enriched with nitrogen and impoverished with oxygen. This air is produced by passage under pressure of atmospheric air through plant having two alternately operating adsorbers adsorbing oxygen and water vapors. Adsorbers are used in form of carbon molecular sieves. Release of vapor-gas mixture may be accomplished by pumping-out by compressor and supplying of mixture under pressure to plant having two alternately operating adsorbers adsorbing oxygen, vapors of oil products and water. Cleaned gas inert mixture, freed of vapors of oil products is accumulated for their repeated use, and vapors of oil products are returned to storage tanks. EFFECT: higher efficiency. 16 cl, 6 dwg
