AS ISO 6396 pdf download

AS ISO 6396 pdf download.Earth-moving machinery — Determination of emission sound pressure level at operator’s position — Dynamic test conditions
1  Scope
This International Standard specifies a method for determining the emission sound pressure level of earth-moving machinery at the operator’s position, measured in terms of the time-averaged A-weighted emission sound pressure level while the machine is operating under dynamic test conditions. It is applicable to earth-moving machinery as defined in ISO 6165 and as specified in ISO 6395:2008, Annex A.
5  Test environment
For the purposes of this International Standard, the test environment specified in ISO 6395 applies.
6  Measurement of time-averaged
A-weighted sound pressure levels 6.1  Operator stature The operator shall have a stature between that of the small operator and the large operator as defined in ISO 3411. See also 6.2.2.2. 6.2  Operator presence 6.2.1  Ride-on machines 6.2.1.1  Operator’s position The operator shall be in the driving position and observers shall not be in close proximity or in the cab during sound measurement. The operator shall wear neither abnormally sound-absorptive clothing nor any hat or scarf (other than a protective helmet used for safety reasons, or a helmet or frame used to support a microphone) which might influence the noise measurement. 6.2.1.2  Seat adjustment The seat shall be set at, or as near as possible to, the midpoint of its horizontal and vertical adjustment. Any seat suspension shall be adjusted to the operator’s weight. 6.2.2  Pedestrian-controlled machines 6.2.2.1  Operator’s position The operator shall be in the usual working position specified by the manufacturer and observers shall not be in close proximity to the operator during sound measurement. The operator shall wear neither abnormally sound-absorptive clothing nor any hat or scarf (other than a protective helmet used for safety reasons, or a helmet or frame used to support a microphone) which might influence the noise measurement.6.2.2.2  Standing operator The standing operator shall have a stature of 1 715 mm ± 50 mm. 6.3  Microphone 6.3.1  Microphone orientation The microphone shall be oriented horizontally, with its reference direction — as specified by the microphone manufacturer — pointing in the direction in which a person occupying the operator’s position would normally look. 6.3.2  Microphone position As a preliminary sound pressure level data check point, the microphone shall be located 200 mm ± 20 mm from the median plane of the head of the operator and in line with the eyes, on the left side and on the right side of the head of the operator, during the maximum governor engine speed (high idle) condition and with the machine in a static mode, as a preliminary sound pressure level data check point. Whichever side yields the highest reading shall be used for the dynamic check. If both initial sound pressure level checks are the same, the right side location shall be used.6.3.3  Microphone mounting The microphone can conveniently be mounted on a frame or on the helmet, or on a shoulder harness worn by the operator. 6.3.4  Microphone vibration precautions Care shall be taken to isolate the microphone from vibrations which could affect the measurements. If the microphone is moved during the measurements, care shall be exercized to avoid introducing acoustical noise (for example, noise due to the microphone rubbing against the operator’s clothing) or electrical noise (for example, due to a flexing cable) that could interfere with the measurements. 6.3.5  Precautions against microphone-reflected noise 6.3.5.1 Care shall be taken to minimize the effect of reflected noise which could affect microphone measurements. The recommendations given in 6.3.5.2 and 6.3.5.3 will minimize the effect of reflected noise. 6.3.5.2 Once the microphone location has been determined, a positional tolerance should be maintained of ± 50 mm from this location in any direction during the test. 6.3.5.3 The microphone should be placed a minimum of 100 mm from the side of the head and a minimum of 50 mm above the clothing on the shoulder during the test.