Document ID: chunk:federal_register_of_legislation:F2021C00509:reg:6:p11
Version: federal_register_of_legislation:F2021C00509
Segment Type: reg
Provision Reference: reg 6 (pt 11/15)
Character Range: 187297–190607

with automatic transmission, it shall be driven at the speeds indicated in 3.1.2.1.

          3.2.                                         MEASUREMENT OF NOISE EMITTED BY STATIONARY MOPEDS (conditions and method of measurement for testing vehicles in service) .

          In addition, in order to facilitate subsequent testing of mopeds in service, the sound pressure level shall be measured close to the outlet of the exhaust (silencing) system, in accordance with the following requirements, and the reading shall be recorded in the test report prepared for the issue of the document referred to in annex l.
          The measurements shall be made using a precision sound-level metre conforming to the requirements of paragraph l.

          3.2.1.                                   Test site - local conditions (see appendix, fig. 2)

          3.2.1.1.                             Measurements shall be made on a stationary moped in an area which does not present a great deal of disturbance to the sound field.

          3.2.1.2.                             Every open space shall be considered as a suitable test site if it consists of a flat area covered with concrete, asphalt or some other hard material having a high reflective capacity, excluding compressed or other earth surfaces, in which one can trace a rectangle whose sides are at least three metres from the extremities of the moped and inside which there is no noticeable obstacle; in particular, the moped shall not be positioned at a distance of less than 1 m from a pavement edge when the exhaust noise is measured.

          3.2.1.3.                             Nobody shall be in the measurement area, except the observer and the driver, whose presence must have no influence on the meter reading.

          3.2.2.                                   Disturbance noise and wind interference

          The ambient noise levels at each measuring point shall be at least 10 dB(A) below the levels measured during the tests at the same points.

          3.2.3.                                   Measuring method

          3.2.3.1.                             Nature and number of measurements

          The maximum sound level expressed in A-weighted decibels (dB(A)) shall be measured during the period of operation laid down in paragraph 3.2.3.3.2.1. below.
          At least three measurements shall be taken at each measuring point.

          3.2.3.2.                             Position and preparation of the moped

          Before the measurements are started, the moped engine shall be brought to its normal operating temperature. If the moped is equipped with automatic fans, no adjustment shall be made to them during the measurement of the noise level.
          While measurements are being made, the gear lever shall be in neutral. If the transmission cannot be disconnected, the drive wheel of the moped should be allowed
          to run under no-load conditions by, for example, placing the moped on its stand.

          3.2.3.3.                             Measuring of noise in proximity to the exhaust (see appendix, fig.2)

          3.2.3.3.1.                       Position of the microphone

          3.2.3.3.1.1.                The height of the microphone above the ground must be equal to that of the