Reactive Silencers

The Howden family of attenuators, or reactive silencers, has been developed specifically for applications where dust or moisture affect the attenuation properties of conventional absorptive silencers.

Conventional absorptive silencers have been used successfully over the years to handle clean air. However they do not perform as well in gas streams containing particulate matter and moisture as the absorptive material deteriorates and plate perforations become blocked.

Howden has developed a range of reactive silencers that are ideally suited for use with contaminated air and gases, or where there is moisture carry over.

Reactive Silencer

Key Features

  • Our pure reactive silencers are based on the Helmholz resonator principle, and have a series of tuned resonator cavities that attenuates excessive and unwanted noise. Since there are no perforated plates or absorptive material that can deteriorate, the silencer will operate over the life of the plant with minimum maintenance. Equipment we installed over 25 years ago is still within the original specified aerodynamic and acoustics limits. Our reactive dissipative attenuators provide a lower cost alternative for handling contaminated air and gas streams. They incorporate reactive chambers for attenuation of specific frequencies and absorptive fill material for broadband attenuation. The downstream faces of the chambers are lined with absorptive fibreglass material to reduce broadband noise. The fibreglass is situated out of the air stream, shielding it from contamination by particulate matter.


  • ​​Long service life
  • Non-fouling design
  • Minimum maintenance
  • Easy cleaning
  • Low pressure drop
  • Flexibility of design
  • Suitable for high temperatures
  • Broad attenuation range
  • Available in various materials


  • ​​Induced draught fan system
  • Contaminated gas streams
  • Saturated gas streams
  • Corrosive gas streams
  • High temperatures
  • Steam vent systems
  • Mine ventilation

If you would like to submit an enquiry please get in touch.