The objective of this Standard is to specify four methods for the determination of the sound power levels of high-frequency noise emitted by machinery and equipment in the frequency range covered by the octave band centred at 16 kHz, which includes frequencies between 11,2 kHz and 22,4 kHz. They are complementary to the methods described in ISO 3741 and ISO 3744.
Table of contents
Header
About this publication
Preface
Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Conformity requirements
5 Requirements for measurements in a reverberation test room
5.1 General
5.2 Meteorological conditions
5.3 Instrumentation
5.4 Installation and orientation of microphone
5.5 Installation and orientation of equipment
5.6 Calibration of measurement system
5.7 Measurement of sound pressure level
6 Method using measured reverberation time
6.1 General
6.2 Measurement of reverberation time
6.3 Calculation of room absorption
6.4 Installation of microphone and equipment
6.5 Measurement of sound pressure level
6.6 Calculation of sound power level
7 Method using calculated air absorption
7.1 General
7.2 Calculation of room constant
7.3 Installation of microphone and equipment
7.4 Measurement of sound pressure level
7.5 Calculation of sound power level
8 Method using a reference sound source
8.1 Reference sound source
8.2 Installation of microphone and equipment
8.3 Installation of reference sound source
8.4 Measurement of sound pressure level
8.5 Calculation of sound power level
8.5.1 Equipment emitting broad-band noise
8.5.2 Equipment emitting discrete tone(s)
9 Method using a free field over a reflecting plane
9.1 General
9.2 Meteorological conditions
9.3 Instrumentation
9.4 Installation and orientation of microphone
9.5 Installation of equipment
9.6 Calibration of measurement system
9.7 Measurement of sound pressure level
9.8 Calculation of surface sound pressure level and sound power level
10 Calculation of sound power level under reference meteorological conditions
