Noise from motor vehicles : interim report / Committee on the Problem of Noise.

  • Great Britain. Committee on the Problem of Noise
Date:
[1962]
Catalogue details

Licence: Public Domain Mark

Credit: Noise from motor vehicles : interim report / Committee on the Problem of Noise. Source: Wellcome Collection.

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    Practice in other countries 40. We have examined the information available on the quantitative noise limits introduced in other countries [(d) of paragraph 26]. Unfortunately, the methods of test used, most of which were introduced before the ISO proposals were drafted, vary considerably and no comparison with them is fruitful. As far aS we are aware, France is the only country which has adopted limits for noise from motor vehicles using a test procedure which 1s similar to that set out in British Standard 3425:1961. However, the French method differs from the British Standard method in the way in which the gear ratio and initial speed of the vehicle are chosen, and the noise limits are different from those that we recommend. Tests have been made by the Motor Industry Research Association on a selection of British vehicles using the BS method and our proposed noise levels and the French pro- cedures and noise levels. These tests have shown that, generally, the two sets of requirements would pass or fail the same vehicles, but that the French requirements are likely to be a little more onerous than our proposals for commercial vehicles and a little less onerous for high performance cars and motor cycles. SECTION V CONCLUSIONS AND RECOMMENDATIONS 41. We have considered it of the greatest importance that any recom- mendations made should be simple to administer and should be related to existing measuring instruments and to procedures in which some experience already existed. No worse service to the cause of noise control could be done than to attempt to impose regulations which could not in fact be administered and which did not carry the support of public opinion. 42. We were informed by the Ministry of Transport that they had con- sidered, and had discussed with representatives of the motor cycle manu- facturing industry, the possibility of introducing quantitative noise limits for motor cycles by voluntary agreement within the industry. While the manufacturers expressed willingness to co-operate in this way, there was some fear that those who achieved reductions of noise at the expense, perhaps, of some reduction in power output, coupled with higher costs, might be placed at a disadvantage if other firms ignored the agreement. They felt that an obligatory upper limit binding on all manufacturers would be preferable. 43. We have considered whether different maximum noise limits should be fixed for different types of vehicles. We have concluded that, in prin- ciple, different limits would be justified only if they reflected the differing performance of the sound level meter for different types of noise. The experiment conducted by the National Physical Laboratory and the Motor Industry Research Association which is referred to in paragraph 30 et seq. did, in fact, show that, for equal noise judged subjectively, the meter reading was higher for motor cycles than it was for cars and commercial vehicles. New vehicles 44. Bearing in mind the considerations of paragraphs 26-40, we there- fore recommend that legislation should be introduced to provide that, after
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