An apparatus for catalytic decomposition of nitrous oxide

A method for catalytic decomposition of nitrous oxide in a gas stream, which is derived from exhalation air from a patient, in an apparatus comprising a casing housing one or more catalyst beds comprising a catalyst material promoting the decomposition of nitrous oxide,

• wherein the casing comprises a gas inlet for a first gas stream derived from exhalation air from a patient,
• wherein the casing comprises one or more gas outlets,
• wherein the apparatus comprises one or more tubular members,
• wherein the casing houses at least a portion of the tubular member,
• wherein the tubular member comprises a gas inlet for a second gas stream comprising at least a portion of the first gas stream,
• wherein the tubular member comprises one or more gas-permeable walls, wherein the method comprises:
• receiving the second gas stream via the gas inlet for the second gas stream;
• guiding at least a portion of the second gas stream in the tubular member;
• and
• providing one or more third gas streams from the tubular member to the catalyst bed through the one or more gas-permeable walls, the third gas stream comprising at least a portion of the second gas stream.