Steam exhaust silencers (also: tension release silencers) are often placed behind safety equipment such as valves or flaps. When these open, a large amount of steam flows, with an overpressure, into the tension release expansion stage (perforated steel plate throttle) which has been fitted with a silencer. In the upper part of the silencer there are sound-absorbing fittings, which reduce the noise of the valve and the flow noise according to the sound requirements.