Abstract: A system for collecting and removing leaking anesthesia or analgesia gas from an anesthesia apparatus in an operation theater or the like includes a vacuum source (1) and an anesthesia mask (5) adapted to be placed onto the face of a patient and connected to the anesthesia apparatus by at least one supply and removing device, through which the patient is supplied with a mixture of anesthesia or analgesia gas and air and through which air-gas mixture exhaled by the patient is removed, and a vacuum line (4) connected to the anesthesia mask for removing leaking gas to the vacuum source. A T-shaped joint (10) is connected in the vacuum line (4) and has one opening connected by a branch line (11)to the supply and removing device for removing exhaled gas-air mixture via the vacuum source. A noise damping or reducing device (18) is arranged in the vacuum line to reduce disturbing noise as far as possible.