Abstract: In a method for preventing the occurrence of an explosive state in a gas mixture, especially of solvents in air, in an essentially confined space, virtually complete oxidation of at least part of the gas mixture taking place, either the temperature difference .DELTA.T between the temperatures of the gas mixture before and after the oxidation is determined, and if the temperature difference .DELTA.T is greater than a maximal permissible temperature increase .DELTA.T.sub.max, safety measures are taken, or the temperature T.sub.1 of the gas mixture before the oxidation and the temperature T.sub.2 of the gas mixture after the oxidation are measured, and the measured temperatures T.sub.1 and T.sub.2 are compared with a minimum temperature T.sub.min before oxidation of the gas mixture and a maximum temperature T.sub.max after oxidation of the gas mixture, the difference between T.sub.max and T.sub.min being less than, or equal to, the maximal permissible temperature increase .DELTA.T.sub.