EN ISO 7235:2009

Acoustics - Laboratory measurement procedures for ducted silencers and air-terminal units - Insertion loss, flow noise and total pressure loss (ISO 7235:2003) EN ISO 7235:2009

Publication date:   Jan 30, 2010

General information

60.60 Standard published   Aug 5, 2009

CEN

CEN/TC 211 Acoustics

European Norm

91.120.20   Acoustics in building. Sound insulation

Buying

Published

Language in which you want to receive the document.

Scope

ISO 7235:2003 specifies methods for determining
the insertion loss, in frequency bands, of ducted silencers with and without airflow,the sound power level, in frequency bands, of the flow noise (or regenerated sound) generated by ducted silencers,the total pressure loss of silencers with airflow, andthe transmission loss, in frequency bands, of air-terminal units.
The measurement procedures are intended for laboratory measurements at ambient temperature. Measurements on silencers in situ are specified in ISO 11820.
It is to be noted that the results determined in a laboratory according to ISO 7235:2003 will not necessarily be the same as those obtained in situ (installation), as different sound and flow fields will yield different results. For example, the pressure loss will be lower under laboratory conditions than in situ, but will be comparable between different laboratories.
ISO 7235:2003 is applicable to all types of silencer including silencers for ventilating and air-conditioning systems, air intake and exhaust of flue gases, and similar applications. Other passive air-handling devices, such as bends, air-terminal units or T-connectors, can also be tested using this International Standard.
It is not applicable to reactive silencers used for motor vehicles.

Related legislation

Legislation related to this standard

98/37/EC

Machinery

2006/42/EC

Directive 2006/42/EC of the European Parliament and of the Council of 17 May 2006 on machinery, and amending Directive 95/16/EC (recast)

Harmonized/Supporting

Life cycle

PREVIOUSLY

WITHDRAWN
EN ISO 7235:2003

NOW

PUBLISHED
EN ISO 7235:2009
60.60 Standard published
Aug 5, 2009

Relations

Adopted from ISO 7235:2003 IDENTICAL