BS ISO 7216:2015 pdf download – Agricultural and forestry tractors — Measurement of noise emitted when in motion
1 Scope
This International Standard specifies a method for measuring the A-weighted sound pressure level ofthe noise emitted by agricultural and forestry tractors while the vehicle is in motion.
The conditions specified for the operation of the agricultural and forestry tractors during themeasurements are defined to provide a realistic and repeatable assessment of the maximum noiseemitted when it is in motion.
This International Standard is applicable to agricultural and forestry tractors,ftted with elastic tyresor rubber tracks.
lt is not applicable to special forestry machinery, for example, forwarders, skidders,etc., as defined inISO 6814 and agricultural and forestry tractors, fitted with steel tracks.
The test method calls for an acoustical environment which can only be obtained in an extensive open
Normative references
The following documents, in whole or in part, are normatively referenced in this document and areindispensable for its application. For dated references,only the edition cited applies.For undatedreferences, the latest edition of the referenced document (including any amendments) applies.
IEC 61672-1,Electroacoustics — Sound level meters
IEC 60942,Electroacoustics — Sound calibrators
ISO 6814:2009, Machinery for forestry — Mobile and self-propelled machinery —Terms, definitions andclassification
3Terms and definitions
For the purposes of this document, the following terms and definitions apply.
agricultural tractor
self-propelled agricultural vehicle having at least two axles and wheels,or endless tracks, particularlydesigned to pull agricultural trailers and pull, push, carry and operate implements used for agriculturalwork (including forestry work), which may be provided with a detachable loading platform
Note 1 to entry: The agricultural vehicle has a maximum design speed of not less than 6 km/h and may beequipped with one or more seats.
[SOURCE: ISO 12934:2013,3.1]
4 Measurement units and tolerances
The following units and tolerances apply to the maximum value measured:
— rotational frequency (r/min) ± 0,5 % ;
— time (s) ± 0,2 s ;
— distance (m or mm) ± 0,5 % ;
— force (N) ± 1,0 % ;
— mass (kg) ± 0,5 % ;
— atmospheric pressure (kPa) ± 0,2 kPa ;
— tyre pressure (Pa) ± 5 % .
5 Instrumentation
5.1 A precision quality sound level meter shall be used meeting or exceeding the requirements of IEC 61672-1 for a class 1 instrument. If alternative measuring equipment is used, the tolerances shall not exceed those given in the relevant clauses of IEC 61672-1 for a class 1 instrument. Measurement shall be carried out with a frequency weighting network in conformity with curve A and set to give fast response as is described in the IEC publication.
5.2 The calibration of the equipment at the time of measurement shall be in accordance in all respects with the specifications of IEC 61672-1 for a class 1 instrument. Checking of the calibration shall be carried out at appropriate intervals and at least before and after each measurement session, using an acoustical calibrator in accordance with the specifications of IEC 60942 for a class 1 instrument. The calibrator shall be checked annually to verify its output and its calibration shall be traceable to a national standards laboratory.
6 Circumstances for testing
6.1 Acoustical environment
6.1.1 Measurements shall be made in a sufficiently silent, flat, and open zone. This area shall be an open space of 50 m radius, of which the central part of at least 20 m radius shall be practically level and made concrete, asphalt, or similar material and shall not be covered with powdery snow, high grass, friable soil or cinders.
6.1.2 The surface of the test track shall be of such a kind that pneumatic tyres or rubber tracks do not cause excessive noise. The surface shall be as clean and dry as possible (e.g. free of gravel, leaves, snow, etc.).
6.2 Ambient conditions
6.2.1 Measurements shall be made in fine weather with little or no wind. The level of background noise and the level of wind noise at the microphone location shall be at least 10 dB(A) below the noise level measured during the test. Any extraneous noise occurring during the reading, which is not connected to general sound level measurement, shall not be taken into consideration.
6.2.2 No correction shall be made to the test results for the atmospheric conditions or other factors. Atmospheric pressure shall not be less than 96,6 kPa. If this is not possible because of conditions of altitude, a modified injection pump setting may have to be used, details of which will be included in the report.