Method for the removal of volatile anesthetic agents from breathing gas in an apparatus for respirating of patients provided with a closed line or conduit system in which breathing gas may be circulated, comprising leading the breathing gas or a part thereof through a filtering apparatus with activated carbon, wherein the breathing gas is cooled to a temperature below the boiling point of the anesthetic agent when it passes through the filtering apparatus, characterized in that the breathing gas, after anesthetic agent has condensed out of it, is warmed.
