BS 4196-5:1981

National foreword
Cooperating organizations
Method
0.1 Related International Standards
0.2 Synopsis of ISO 3745
0.3 Introduction
1 Scope and field of application
2 References
3 Definitions
4 Test room requirements
5 Instrumentation
6 Installation and operation of source
7 Determination of mean-square pressure
8 Calculation of sound power level
9 Information to be recorded
10 Information to be reported
Annexes
A Test room qualification procedures
B Recommended array of microphone positions in a free
     field
C Basic array of microphone positions in a free field
     over a reflecting plane
D Coaxial circular paths in parallel planes for
     microphone traverses in a free field over a
     reflecting plane
E Calculation of directivity index and directivity
     factor
F System for microphone traverses along meridional
     paths in a free field
G Guidelines for the design of test rooms
H Examples of suitable instrumentation systems
I Guidelines for the detection of impulsive noise
Tables
1 International Standards specifying various methods
     for determining the sound power levels of machines
     and equipment
2 Uncertainty in determining sound power levels of
     sound sources in anechoic rooms
3 Uncertainty in determining sound power levels of
     sound sources in semi-anechoic rooms
4 Relative tolerances for the instrumentation system
5 Corrections for background sound pressure levels
6 Maximum allowable differences between the measured
     and theoretical values
7 Microphone positions
8 Recommended microphone positions when the source
     emits predominant pure tones
Figures
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