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Compact sound attenuator with centre baffle for circular ducts
  • Equipped with an acoustic centre baffle
  • Extremely low installation height
  • Very good sound attenuation
  • Fibre-migration proof
  • Dim up to 400 air tightness class D
  • Dim 500 to 800 air tightness class C
  • Low pressure drop
  • Mineral wool
  • Galvanised sheet steel to Environmental Class C3
  • Fire-resistance class EI30 to EI120*
    * See the table for requisite safety distance

  • The CLA-B is a rectangular sound attenuator for connection to circular ducts, is equipped with an acoustic centre baffle for improved sound attenuation data. The installation height is as much as 80 mm lower than equivalent conventional sound attenuators.
  • CLA-B up to size 400 is type approved (TG SC0478-18) in terms of fire-resistance class E120. EI30, EI60 and EI120 are met provided that the safety distance is realised.
  • The CLA-B up to dim 400 is fibre-migration-proof thanks to our solution with self-supporting surface layer FarTex®, which is approved with regard to cleaning, fibre migration, resistance to ageing, emissions.
  • The CLA-B dim 500 to 800 is an excellent option, for kitchen flues for instance (held by means of a fixing clamp for simple removal for cleaning.