BS 7135-2:1989
Withdrawn
A Withdrawn Standard is one, which is removed from sale, and its unique number can no longer be used. The Standard can be withdrawn and not replaced, or it can be withdrawn and replaced by a Standard with a different number.
A Withdrawn Standard is one, which is removed from sale, and its unique number can no longer be used. The Standard can be withdrawn and not replaced, or it can be withdrawn and replaced by a Standard with a different number.
Noise emitted by computer and business equipment Method of measurement of high-frequency noise
Hardcopy , PDF
10-26-2018
English
09-29-1989
National foreword
Committees responsible
Method
0 Introduction
1 Scope and field of application
2 References
3 Requirements for measurements in a reverberation
room
4 Method using measured reverberation time
5 Method using calculated air absorption
6 Method using a reference sound source
7 Method using a free field over a reflecting plane
8 Calculation of A-weighted sound power level
9 Information to be recorded
10 Information to be reported
Annexes
A Coaxial circular paths in parallel planes for
microphone traverses in a free field over a
reflecting plane
B Calculation of air absorption coefficient
Tables
1 Air absorption coefficients
2 Values of the A-weighting factor, Aj, for j = 1 to
24
3 Type of noise and determination of sound power
levels
Figure
A.1 Circular paths for microphone traverses
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