DIN EN ISO 3744:2009 Acoustics - Determination of sound power levels of noise sources using sound pressure - Engineering method in an essentially free field over a reflecting plane (ISO 3744:1994); English version of DIN EN ISO 3744:2009-11
1.1 General
This International Standard specifies a method for
measuring the sound pressure levels on a measure-
ment surface enveloping a noise source, under es-
sentially free-field conditions near one or more
reflecting planes, in order to calculate the sound
power level produced by the noise source. It gives
requirements for the test environment and instru-
mentation, as well as techniques for obtaining the
surface sound pressure level from which the sound
power level of the source is calculated, leading to re-
sults which have a grade 2 accuracy.
It is important that specific noise test codes for vari-
ous types of equipment be established and used in
accordance with this International Standard. For each
type of equipment, such noise test codes will give
detailed requirements on mounting, loading and op-
erating conditions for the equipment under test as
well as a selection of the measurement surface and
the microphone array as specified in this International
Standard.
NOTE 1 The noise test code for a particular type of
equipment should give detailed information on the particular
surface that is selected, as the use of differently shaped
measurement surfaces may yield differing estimates of the
sound power level of a source.
1.2 Types of noise and noise sources
The method specified in this International Standard is
suitable for measurements of all types of noise.
NOTE 2 A classification of different types of noise
(steady, non-steady, quasi-steady, impulsive, etc.) is given in ISQ 2204.
This International Standard is applicable to noise
sources of any type and size {e.g. device, machine,
component, sub-assembly).
NOTE 3 Measurements according to this International
Standard may be impracticable for very tall or very long
sources such as chimneys, ducts, conveyors and multi-
source industrial plants.
1.3 Test environment
The test environment that is applicable for measure-
ments made in accordance with this International
Standard is an essentially free field near one or more
reflecting planes (indoors or outdoors).
DIN EN ISO 3744:2009 history
2023DIN EN ISO 3744:2023-02 Acoustics - Determination of sound power levels of noise sources using sound pressure - Engineering methods for an essentially free field over a reflecting plane (ISO/DIS 3744:2023); German and English version prEN ISO 3744:2023 / Note: Date of issue 2...
2023DIN EN ISO 3744:2023 Acoustics - Determination of sound power levels of noise sources using sound pressure - Engineering methods for an essentially free field over a reflecting plane (ISO/DIS 3744:2023); German and English version prEN ISO 3744:2023
2014DIN EN ISO 11200:2014 Acoustics - Noise emitted by machinery and equipment - Guidelines for the use of basic standards for the determination of emission sound pressure levels at a work station and at other specified positions (ISO 11200:2014); German version EN ISO 11200:2014
2010DIN EN ISO 11200:2010 Acoustics - Noise emitted by machinery and equipment - Guidelines for the use of basic standards for the determination of emission sound pressure levels at a work station and at other specified positions (ISO 11200:1995, including Cor 1:1997); German vers
1970DIN EN ISO 11200:1996 Acoustics - Noise emitted by machinery and equipment - Guidelines for the use of basic standards for the determination of emission sound pressure levels at a work station and at other specified positions
1984DIN 45635-1:1984 Measurement of noise emitted by machines; airborne noise emission; enveloping surface method; basic method, divided into 3 grades of accuracy