1. A silencer affects only noise resulting from air turbulence within the fan. It does not affect noise radiated through the fan housing, mechanical noise produced by the motor & drive, or noise produced by vibration.
  2. Radiated noise can be reduced by insulating the fan housing and/or enclosing the fan. Mechanical noise produced by the motor and drive can be reduced by enclosing the fan.
  3. Sound pressure levels vary with characteristics of a given fan location (surrounding equipment, walls, outdoor or indoor environment, etc.). Therefore sound pressure levels cannot be guaranteed at an installation site.
  4. Silencers are intended to be supported externally (by others). Fans are not designed to support silencers.