Machines: Determination of emission sound pressure levels using sound intensity (NT ACOU 097)

  • Report #: NT ACOU 097
  • Approved: May 1997
Download pdf Size: 38.85 KB

Abstract

This NORDTEST method specifies how to determine theemission sound pressure level at the work station or at other specified positions of machines using sound intensity. The method supplements IS0 11201 and it applies to all kinds of test environments as long as the requirements on background noise and field indicator are fulfilled and as long as the environmental indicator, KM, as defined in IS0 11201 is larger than 2 dB. Note 1 If the method is applied on a machine located in front of a reflecting wall or in a corner the result will be the emission sound pressure level corresponding to the one obtained in a hemi-anechoic room with the machine in front of one and two reflecting panels respectively. Note 2 K,, < 2 dB has been excluded because in this case IS0 11201 is valid and there is no need for this Nordtest method. The method is applicable to equipment operating under steady state conditions and emitting broad-band noise with or without discrete-frequency or narrow-band components. The method yields results comparable with those of IS0 11201 and 11204.