BS ISO 7216:2015 pdf free
BS ISO 7216:2015 pdf free.Agricultural and forestry tractors – Measurement of noise emitted when in motion
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.
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.
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.
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.).
Measurements shall be made in fine weather with lttle 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.
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.BS ISO 7216 pdf download.