BS EN ISO 7779:2018,Acoustics – Measurement of airborne noise emitted by information technology and telecommunications equipment.
BS EN ISO 7779:2018 specifies procedures for measuring and reporting the noise emission of information technology and telecommunications equipment.
BS EN ISO 7779:2018 specifies methods for the measurement of airborne noise emitted by informatio technology and telecommunications (ITT) equipment. Hitherto, a wide variety of methods have been applied by individual manufacturers and users to satisfy particular equipment or application needs These diverse practices have, in many cases, made comparison of noise emission difficult. This document simplifies such comparisons and is the basis for the declaration of the noise emission levels of ITT equipment.
In order to ensure accuracy, validity and acceptability, this document is based on the basic International Standards for determination of the sound power level and for determination of the emission sound pressure level at the operator position and bystander positions. Furthermore, implementation is simplified by conformity with these International Standards.
In many cases, free-field conditions over a reflecting plane are realised by hemi-anechoic rooms. These rooms can be particularly useful during product design to locate and to improve individual contributing noise sources. Reverberation test rooms can be more economical for production control and for obtaining sound power levels for noise emission declaration purposes.
The method for measuring the emission sound pressure level at the operator or bystander positions (based on ISO11201) is specified in a separate clause, as this level is not considered to be primary noise emission declaration information. The measurements can, however, be carried out in conjunction with those for sound power determination in a free field over a reflecting plane.
For comparison of similar equipment, it is essential that the installation conditions and mode of operation be the same, In Annex C, these parameters are standardized for many categories of equipment.
This document is based on ECMA-74.