Explains engineering methods for measuring the sound pressure levels on a measurement surface enveloping the source and for calculating the sound power level produced by the source. Gives requirements for the test environment and instrumentation as well as techniques for obtaining the surface sound pressure level from which the A-weighted sound power level of the source and octave or one-third octave band sound power levels are calculated. This is concerned with specification of the basic acoustic requirements for the measurement of noise under free-field conditions over a reflecting plane. It is important that specific test codes for various types of equipment be established and used as the basis for measurements.

BS ISO 3744 : 1994 AMD 8936

BS EN ISO 3744 : 2010