Sounders on Sound
Page 34
If you've noticed an error in this article please click here to report it so we can fix it.
LTHOUGH Mr. G. R. H. Nugent, Parliamentary Secretary to the Ministry of Transport, recently forecast in the House of Commons that more precise regulations would eventually be made to control the noise emitted by vehicles, it is difficult to visualize a suitable formula. The amount of noise legally permitted to be made by pneumatic drills is determined in decibels, but it would hardly be practicable to apply this test to a commercial vehicle.
A voluntary agreement on the subject exists between the Ministry of Transport and motorcycle manufacturers, but this, again, could scarcely be extended to commercial vehicles. Probably all the sound emitted by a motorcycle which is detectable by the ear comes from the engine, but this is certainly not the case with a commercial vehicle.
Gear noise is a not unsubstantial part of the total volume of sound. Mr. Nugent foresaw the increasing adoption of automatic transmissions for goods vehicles as a solution of the noise problem, but there is no evidence of a trend in this direction. The synchromesh gearbox is likely to remain supreme for some time.
The hum of large tyres, which varies according to the road surface, must also be taken into account. An even more uncertain factor is the noise caused by certain kinds of load which cannot be properly secured to make them silent. They are just as important to the trade of the country as any other, and legislation could not be directed against them in particular.
The control of noise in commercial vehicles is so complicated that it would be impossible to lay down a maximum standard of decibels that would be applicable under all conditions. Although it is easy to sympathize with those to whom noise is an unmitigated nuisance, its regulation in all circumstances is impracticable. It is one of the penalties which society has to pay for the advance of mechanization and all the other counterbalancing amenities which it brings.