Acoustics — Measurement of airborne noise emitted by information technology and telecommunications equipment

This document specifies procedures for measuring and reporting the noise emission of information technology and telecommunications equipment.

NOTE 1 This document is considered part of a noise test code (see 3.1.2) for this type of equipment and is based on basic noise emission standards (see 3.1.1) ISO 3741, ISO 3744, ISO 3745, ISO 9295 and ISO 11201.

The basic emission quantity is the A-weighted sound power level, which can be used for comparing equipment of the same type but from different manufacturers, or for comparing different equipment.

Three basic noise emission standards for determination of the sound power levels are specified in this document in order to avoid undue restriction on existing facilities and experience. ISO 3741 specifies comparison measurements in a reverberation test room; ISO 3744 and ISO 3745 specify measurements in an essentially free field over a reflecting plane. Any of these three basic noise emission standards can be selected and used exclusively in accordance with this document when determining sound power levels of a machine.

The A-weighted sound power level is supplemented by the A-weighted emission sound pressure level determined at the ope