Air terminal devices: Acoustic transmission loss (NT ACOU 105)

  • Report #: NT ACOU 105
  • Approved: April 2000
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The method describes a test arrangement and procedure for measuring transmission loss without flow of duct-mounted air terminal devices. This is a laboratory substitution method, which is to be applied in a reverberation room. The method defines that the end reflection of the duct shall be included in the reported transmission loss. The result obtained may be used to compare products and for the calculation of noise from normal ventilation systems.


Acoustic | NT Methods