Document ID: chunk:federal_register_of_legislation:F2021C00509:reg:6:p9
Version: federal_register_of_legislation:F2021C00509
Segment Type: reg
Provision Reference: reg 6 (pt 9/15)
Character Range: 181809–184734

of a central acceleration track surrounded by a substantially level test area. The test track shall be level ; the track surface shall be dry and so designed that rolling noise remains low.
          On the test site, free sound field conditions shall be maintained to within 1 dB between the sound source placed in the middle of the acceleration section and the microphone. This condition shall be deemed to be met if there are no large sound reflecting objects such as hedges, rocks, bridges or buildings within 50 m of the centre of the acceleration section.
          No obstacle likely to affect the sound field shall be close to the microphone and no one shall come between the microphone and the sound source. The observer taking the measurements shall take up position so as to avoid influencing the metre readings.

          2.1.2.                                   The surface of the test track shall conform to the requirements of annex 5 .

          2.1.3.                                   Miscellaneous

          Measurements shall not be made in poor weather conditions. Precautions shall be taken to ensure that readings are not influenced by wind gusts.
          For measurement purposes, the weighted sound-level (A) of sound sources on the test vehicle and the sound-level produced by the effect of the wind shall be at least 10 dB(A) below the noise-level produced by the vehicle. The microphone may be fitted with a suitable wind guard, provided that its influence on the sensitivity and directional characteristics of the microphone are taken into account .
          If the difference between ambient and measured noise-levels is between 10 and 16 dB(A), the appropriate figure shall be subtracted from the value recorded by the sound-level metre, in accordance with the following graph:

          2.2. Moped

          2.2.1. The combined mass of the driver and test equipment used on the moped shall not be
          more than 90 kg, or less than 70 kg.
          Weights shall be placed on the moped if the 70 kg minimum is not reached.
          While measurements are being taken, the moped shall be equipped as for normal road
          use (with coolant, lubricants, fuel, tool kit, spare wheel and driver) .

          2.2.2. The tyres of the moped shall be of the correct size and shall be inflated to the prescribed pressure(s) for the moped in its unladen condition.

          2.2.3. Before the measurements are started, the engine shall be brought to its normal operating conditions as regards:

2.2.3.1. temperatures

2.2.3.2. tuning

2.2.3.3. fuel

2.2.3.4. sparking plugs, carburettor (s), etc., (as appropriate).

          2.2.4. If the moped is equipped with devices which are not necessary for its propulsion, but which are used whilst the moped is in normal service on the road, those devices shall be in operation in accordance with the specifications of the manufacturer.