The prime requirement for a vent silencer is its ability to handle with total reliability the rapid release of large quantities of steam from high pressure to atmosphere and attenuating high levels of noise generated at the vent for steam at wide range of pressure and temperature conditions. The silencers are made out of concentric annular acoustic cylinders enclosed with a robust steel casing with dished end or flat end at one end.

The fluid enters through the diffuser and passes through the annular space between the acoustic packing where the sound energy is absorbed. The straight flow path through the annular acoustic cylinders ensure minimum pressure drop. A weather cowl for rain protection is available as an optional item.