NBN EN 13141-4:2004

This European standard specifies performance test methods for fans used in the residential ventilation. These methods primarily concern: a) Ventilation fans installed on a wall or in a window without any duct; b) Ventilation fans installed in the downstream of a duct; c) Ventilation fans installed in the upwardstream of a duct; d) Ventilation fans installed in a duct; e) Encased fans having several inlets. This standard defines for each type of fan, the acoustic testing methods. The following method can be used: a) In duct method; b) Reverberant field method; c) Free field or semi-reverberant method.