Method for detecting and preventing leaks

A method for detecting and preventing leaks in a double-walled container for the storage of poisonous, caustic, irritant and/or combustible media, wherein the double-walled container has an inner wall and an outer wall, wherein a cavity is formed between the inner wall and the outer wall, wherein a positive pressure is generated in the cavity, and wherein a gas is supplied to the cavity if the inner wall springs a leak in order to maintain a positive pressure in the cavity, wherein the positive pressure in the cavity is measured and the pressure and/or the throughflow of the gas being supplied to the cavity is controlled in such a way that the positive pressure in the cavity relative to the pressure in the interior of the double-walled container lies between 5 mbar and 50 mbar, wherein a liquid stored in the double-walled container, which escapes from this container due to a leak in the inner wall and accumulates in the cavity, is conveyed into a monitoring container via a drainage line at the lowest point of the cavity, wherein the monitoring container is partially filled with another liquid.