Document ID: chunk:federal_register_of_legislation:F2018L01513:body:0:p21
Version: federal_register_of_legislation:F2018L01513
Segment Type: other
Provision Reference: 
Character Range: 61483–64460

Model A

       The above approval mark affixed to a vehicle indicates that, pursuant to UN Regulation No. 28, this vehicle type has been approved in the Netherlands (E 4), with regard to its audible warning signals. The first two digits of the approval number indicate that UN Regulation No. 28 was in its original form.

       Model B

The above approval mark affixed to a vehicle shows that the vehicle type concerned has been approved in the Netherlands (E 4) pursuant to UN Regulations Nos. 28 and 33.[24] The approval numbers indicate that, at the dates when the respective approvals were granted, UN Regulation No. 28 and UN Regulation No. 33 were in their original form.
Annex 3
  Qualification criteria for anechoic environment
The anechoic environment shall meet the requirements of ISO 26101:2012 with the following qualification criteria and measurement requirements appropriate to this test method. For qualifying the acoustic space, the following evaluation shall be conducted:
•   Sound source location shall be placed in position of the audible warning device, audible warning system, multiple audible warning system to be tested;
•   Sound source shall provide a broadband input for measurement;
•   Evaluation shall be conducted in one-third-octave bands;
•   Microphone locations for evaluation shall be on a line from the source location to position of the microphone used for measurement. This is commonly referred to as the microphone traverse; only one microphone traverse line from the microphone to sound source shall be used;
•   A minimum of 10 points shall be used for evaluation on the microphone traverse line. The measurement shall start at 0.5 ± 0.05 m from the sound source, and spacing shall be 0.15 m (e.g. Figure 1);
•   The one-third-octave bands used to establish anechoic qualification shall be defined to cover the spectral range of interest from 250 Hz to 10 kHz;
•   The deviations of the measured sound pressure levels from those estimated using the inverse square law, shall not exceed the values given in the following table.
One-third-octave-band frequency (Hz)  Allowable deviations (dB)
≤ 630                                 ±1.5
800 to 5000                           ±1.0
≥ 6300                                ±1.5

              Figure 1

              (All dimensions are in m)

Annex 4
  Microphone positions for measurements of acoustics parameters of audible warning device, audible warning system, multiple audible warning system
 A.  In case of an audible warning device
All dimensions are in m
 B. In case of audible warning system
The reference point is the centre of a figure connecting the sound emitting opening centre of each audible warning device.
All dimensions are in m

Annex 5
  Microphone positions for measurements of audible warning signals of motor vehicles

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* The category code may also be in the format L1, L2, L3 etc
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