BS 848-2.6:2000
Fans for general purposes - Methods of noise testing - Airborne noise emitted by small air-moving devices - Section 6: Airborne noise emitted by small air-moving devices

Standard No.

BS 848-2.6:2000

Release Date

2000

Published By

British Standards Institution (BSI)

Status

Be replaced 2011-01

Replace By

BS ISO 10302-1:2011

Latest

BS ISO 10302-1:2011

Scope

1 This International Standard specifies a method for measuring the airborne noise emitted by small air-moving devices such as those used for cooling electronic, electrical and mechanical equipment. These air-moving devices include such types as propeller fans, tube-axial fans, vane-axial fans, centrifugal blowers, transverse blowers, cabinet blowers and variations of these types. This International Standard describes a method and the test apparatus for determining and reporting the airborne noise emitted by small air-moving devices as a function of the airflow and the fan static pressure developed by the air-moving device on the test apparatus. It is intended for use by air-moving device manufacturers, by manufacturers who use air-moving devices for cooling electronic equipment and similar applications, and by testing laboratories on behalf of these manufacturers. Results of measurements made in accordance with this International Standard are expected to be used for engineering information and performance verification, and the method may be cited in purchase specifications and contracts between buyers and sellers. The ultimate purpose of the noise emission measurements is to provide data to assist the designers of electronic, electrical or mechanical equipment which contains one or more air-moving devices. 2 This International Standard is applicable to small air-moving devices used for cooling electronic equipment and for similar applications where the total sound power level of the air-moving device is of interest. Experimental data show that this method is useful up to an airflow of 1 m/s and up to a fan static pressure of 750 Pa. This International Standard is suitable for type tests and provides a method for air-moving device manufacturers, equipment manufacturers and testing laboratories to obtain comparable results. The method defined in this International Standard, by reference to ISO 7779, provides for determination of sound power levels in a qualified environment, using either a comparison method in a reverberation room based on ISO 3741 or ISO 3742 or a direct method in essentially free-field conditions over a reflecting plane based on ISO 3744 or ISO 3745. The method specified in this International Standard may be applied to air-moving devices which radiate broad-band noise, narrow-band noise, or noise that contains discrete frequency components. The method specified in this International Standard permits the determination of noise emission levels for an individual unit under test. If these levels are determined for several units of the same production series, the results may be used to determine a statistical value for the production series using methods described in ISO 7574-4 or in ISO 9296. CAUTION - Vibration, flow disturbances, insertion loss and other phenomena may alter radiated sound power in the actual application; therefore, the results of measurements made in accordance with this International Standard may differ from the results obtained when air-moving devices are installed in equipment. NOTE 1 This International Standard does not describe measurement of the structure-borne noise generated by air-moving devices, and it does not cover measurement of the aerodynamic performance of such devices.

BS 848-2.6:2000 history

• 2011 BS ISO 10302-1:2011 Acoustics. Measurement of airborne noise emitted and structure-borne vibration induced by small air-moving devices. Airborne noise measurement
• 2000 BS 848-2.6:2000 Fans for general purposes - Methods of noise testing - Airborne noise emitted by small air-moving devices - Section 6: Airborne noise emitted by small air-moving devices