The invention relates to the use of a gas or liquid-jet curtain generated by spraying non-flammable gases or liquids for diluting and/or ejecting clouds of flammable gases, the density of which does not exceed the density of air, from containments that have one or more outer openings, and also to a method for diluting and/or ejecting clouds of flammable gases, the density of which does not exceed the density of air, from containments that have one or more outer openings, wherein, by spraying non-flammable gases or liquids at at least one outer opening, a gas or liquid-jet curtain is generated that dilutes the clouds of flammable gases situated in the containment or bears them in the direction of the at least one outer opening and thus ejects them.