ISO/TC 43/SC 1/WG 23 - Measurement of noise from information technology, business 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 operator position or the bystander positions, based on basic noise emission standard ISO 11201. This sound pressure level is not a level of noise immission at a work station (see 3.2.12), but it can assist in identifying any potential problems that could cause annoyance, activity interference or hearing damage to operators and bystanders. Methods for determination of whether the noise emission includes prominent discrete tones are specified in Annex D. This document is suitable for type tests and provides methods for manufacturers and testing laboratories to obtain comparable results. The methods specified in this document allow the determination of noise emission levels for a functional unit (see 3.1.4) tested individually. The procedures apply to equipment which emits broad-band noise, narrow-band noise and noise which contains discrete-frequency components, or impulsive noise. The sound power and emission sound pressure levels obtained can serve noise emission declaration and comparison purposes (see ISO 9296[3]). NOTE 2 The sound power levels and emission sound pressure levels obtained are not intended to be considered as installation noise immission levels; however, they can be used for installation planning (see ECMA TR/27[11]). If sound power levels obtained are determined for a number of functional units of the same production series, they can be used to determine a statistical value for that production series (see ISO 9296[3]).

ISO 9296:2017 is applicable to information technology and telecommunications equipment. It specifies: a) for a batch of equipment, the method for determining the following values: - the declared mean A-weighted sound power level, LWA,m; - the declared mean A-weighted emission sound pressure level, LpA,m; - the statistical adder for verification, Kv; - the statistical upper limit A-weighted sound power level, LWA,c; b) how acoustical and product information is to be published electronically or in hard-copy format in technical documents or other product literature supplied to users by the manufacturer or declarer; c) the method for verifying the noise emission values that are declared by the manufacturer or declarer.

ISO 10302-2:2011 covers vibration levels from small air moving devices (AMDs) with mounting footprints of less than 0,48 m × 0,90 m for the full-size test plenum defined in ISO 10302‑1 and less than 0,18 m × 0,3 m for the half-size plenum. It covers all types of AMDs which can be mounted on, and are self-supported at, the discharge or inlet plane of a test plenum box as specified in ISO 10302‑1. The procedures defined in ISO 10302-2:2011 specify methods for determining the vibration levels that a small AMD would induce in an average structure used in information technology and telecommunications equipment. The methods specified in ISO 10302-2:2011 allow the determination of induced vibration levels for the individual AMD that is tested. These data can be used to determine the statistical values of vibration levels for a production series if levels are measured for several units of that series.

ISO 10302-1:2011 specifies methods for measuring the airborne noise emitted by small air-moving devices (AMDs), such as those used for cooling electronic, electrical, and mechanical equipment where the sound power level of the AMD is of interest. Examples of these AMDs include propeller fans, tube-axial fans, vane-axial fans, centrifugal fans, motorized impellers, and their variations. ISO 10302-1:2011 describes the test apparatus and methods for determining the airborne noise emitted by small AMDs as a function of the volume flow rate and the fan static pressure developed by the AMD on the test apparatus. It is intended for use by AMD manufacturers, by manufacturers who use AMDs for cooling electronic equipment and similar applications, and by testing laboratories. It provides a method for AMD manufacturers, equipment manufacturers and testing laboratories to obtain comparable results. Results of measurements made in accordance with ISO 10302-1:2011 are expected to be used for engineering information and performance verification, and the methods can be cited in purchase specifications and contracts between buyers and sellers. The ultimate purpose of the measurements is to provide data to assist the designers of electronic, electrical or mechanical equipment which contains one or more AMDs. Based on experimental data, a method is given for calculating the maximum volume flow rate of the scaled plenum up to which ISO 10302-1:2011 is applicable.

ISO 7779:2010 specifies procedures for measuring and reporting the noise emission of information technology and telecommunications equipment. The basic emission quantity is the A-weighted sound power level which may 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 ISO 7779:2010 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 one of these three basic noise emission standards can be selected and used exclusively in accordance with ISO 7779:2010 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 operator position(s) or the bystander positions, based on basic noise emission standard ISO 11201. This sound pressure level is not a worker's immission rating level, but it can assist in identifying any potential problems that could cause annoyance, activity interference, or hearing damage to operators and bystanders. Methods for determination of whether the noise emission includes prominent discrete tones or is impulsive in character are specified in annexes. ISO 7779:2010 is suitable for type tests and provides methods for manufacturers and testing laboratories to obtain comparable results. The methods specified in ISO 7779:2010 allow the determination of noise emission levels for a functional unit tested individually. The procedures apply to equipment which emits broadband noise, narrowband noise and noise which contains discrete-frequency components, or impulsive noise. The sound power and emission sound pressure levels obtained can serve noise emission declaration and comparison purposes (see ISO 9296). If sound power levels obtained are determined for a number of functional units of the same production series, they can be used to determine a statistical value for that production series (see ISO 9296).

Contains a method for measuring the airborne noise emitted by small air-moving devices such as those used for cooling electronic, electrical and mechanical equipment. Applicable to up to an airflow of one cubic metre per second and up to a fan static pressure of 750 Pa. Suitable for type tests; provides a method for manufacturers and testing laboratories to obtain comparable results.