scope:

This International Standard describes a method for measuring the weighted sound pressure levels at prescribed microphone positions in the proximity of a device or machine for outdoor use, in order to determine compliance with noise limits. The A-weighted sound power level of the source is calculated from the measured values. This International Standard applies to sources which radiate broad-band noise, narrow-band noise, discrete tones and combinations thereof. Procedures given in this International Standard are primarily applicable to sources that radiate steady noise. These procedures may also be applied to sources that radiate non-steady noise, and impulsive noise, provided that certain precautions are taken. In principle the method given in this International Standard does not restrict the size of the machine to be measured; for very large machines the procedure may, however, lead to microphone positions which are impracticable to use.