ANNEX VI
1. PERMISSIBLE SOUND LEVELS
1.1. Limits
The sound level of the tractors referred to in Article 1 of this Directive, when measured under the conditions set out in this Annex, may not exceed the following levels:
89 dB (A) for tractors with an unladen weight exceeding 1,5 metric tons,
85 dB (A) for tractors with an unladen weight not exceeding 1,5 metric tons.
1.2. Measuring instruments
The noise emitted by tractors shall be measured by means of a sound-level meter of the type described in Publication 179, 1st Edition (1965) of the International Electrotechnical Commission.
1.3. Conditions of measurement
Measurements shall be made on unladen tractors in a sufficiently silent and open area (ambient noise and wind noise at least 10 dB (A) below the noise being measured).
This area may take the form, for instance, of an open space of 50 metres radius having a central part of at least 20 metres radius which is practically level; it may be surfaced with concrete, asphalt, or similar material and may not be covered with powdery snow, tall grass, loose soil or ashes.
The surface of the test track shall be such as not to cause excessive tyre noise. This condition applies only to measurement of the noise made by tractors in motion.
Measurement shall be carried out in fine weather with little wind. No person other than the observer taking the readings from the apparatus may remain near the tractor or the microphone, as the presence of spectators near either the tractor or the microphone may considerably affect the readings from the apparatus. Marked fluctuations of the pointer which appear to be unrelated to the characteristics of the general sound level shall be ignored in taking readings.
1.4. Method of measurement
1.4.1.Measurement of noise of tractors in motion (for type-approval).
At least two measurements shall be made on each side of the tractor. Preliminary measurements may be made for adjustment purposes but shall be disregarded.
The microphone shall be situated 1,2 metres above ground level at a distance of 7,5 metres from the path of the tractor’s centre line, CC, measured along the perpendicular PP’ to that line (figure 1).
Two lines AA’ and BB’, parallel to line PP’ and situated respectively 10 metres forward and 10 metres rearward of the line, shall be marked out on the test track. Tractors shall approach line AA’ at a steady speed, as specified below. The throttle shall then be fully opened as rapidly as practicable and held in the fully opened position until the rear of the tractor(1) crosses line BB’; the throttle shall then be closed again as rapidly as possible.
The maximum sound level recorded shall constitute the result of the measurement.
1.4.1.1.The test speed shall be three-quarters of the maximum speed which can be attained in the highest gear used for road movement.
1.4.1.2.Interpretation of results
1.4.1.2.1.To take account of inaccuracies in the measuring instruments, the result obtained from each measurement shall be determined by deducting 1 dB (A) from the meter reading.
1.4.1.2.2.Measurements shall be considered valid if the difference between two consecutive measurements on the same side of the tractor does not exceed 2 dB (A).
1.4.1.2.3.The highest sound level measured shall constitute the test result. Should that result exceed by 1 dB (A) the maximum permissible sound level for the category of tractor tested, two further measurements shall be made. Three of the four measurements thus obtained must fall within the prescribed limits.
Measuring positions for tractors in motion
1.4.2.Measurement of noise with tractor stationary (not for type-approval, but must be recorded).
1.4.2.1.Position of sound-level meter
Measurements shall be made at point X (shown in figure 2) at a distance of 7 metres from the nearest surface of the tractor.
The microphone shall be situated 1,2 metres above ground level.
1.4.2.2.Number of measurements
At least two measurements shall be made.
1.4.2.3.Tractor test conditions
The engine of a tractor without a speed governor shall be run at three-quarters of the rpm speed at which, according to the tractor manufacturer, it develops its maximum power. The rpm speed of the engine shall be measured by means of an independent instrument, e.g. a roller bed and a tachometer. If the engine is fitted with a governor preventing the engine from exceeding the speed at which it develops its maximum power, it shall be run at the maximum speed permitted by the governor.
Before taking any measurements, the engine shall be brought to its normal running temperature.
1.4.2.4.Interpretation of results
All sound-level readings recorded shall be given in the report.
The method used to calculate the engine power shall also be shown where possible. The state of loading of the tractor must also be given.
The measurements shall be considered valid if the difference between two consecutive measurements on the same side of the tractor does not exceed 2 dB (A).
The maximum figure recorded shall constitute the result of the measurement.
Measuring positions for stationary tractors
2. EXHAUST SYSTEM (SILENCER)
2.1.If the tractor is fitted with a device designed to reduce the exhaust noise (silencer), the requirements of this Item 2 shall apply. If the inlet of the engine is fitted with an air filter which is necessary in order to ensure compliance with the permissible sound level, the filter shall be considered to be part of the silencer, and the requirements of this Item 2 shall also apply to that filter.
The exhaust tailpipe must be positioned in such a way that the exhaust gases cannot penetrate inside the cab.
2.2.A drawing of the exhaust system must be annexed to the tractor type-approval certificate.
2.3.The silencer must be marked with a reference to its make and type which is clearly legible and indelible.
2.4.The use of fibrous absorbent material is permitted in the construction of silencers only if the following conditions are fulfilled:
the fibrous absorbent material may not be placed in those parts of the silencer through which gases pass;
suitable devices must ensure that the fibrous absorbent material is kept in place for the whole time that the silencer is being used;
the fibrous absorbent material must be resistant to a temperature at least 20 % higher than the operating temperature (degrees C) which may occur in the region of the silencer where those fibrous absorbent materials are situated.
If the tractor includes a trailer, this shall not be taken into account in determining when line BB’ is crossed.