MEASUREMENT OF NOISE KAYE 161 



So far in Great Britain, the menace of the public loudspeaker has 

 not attained the dimensions which it has reached in America. Giant 

 sound amplifiers now make it possible to hear the human voice nearly 

 2 miles away, and we learn that last Christmas, carols were broad- 

 cast by this means for 10 hours over an area of some 9 square miles. 

 The center of this acoustical disturbance was the eighty-first floor of 

 the Empire State Building — the latest and highest (1,250 feet) 

 skyscraper in New York. 



As regards the effect of noise on human beings, there would appear 

 to be a volinne of medical testimony in this country that the strain 

 of heavy traffic and other types of continuous din may act as a 

 powerful irritant to the nervous system; placid and normally un- 

 ruffled persons tending to become irritable and " worn out." Indus- 

 tries such as shipbuilding, boilermaking, cotton weaving, and print- 

 ing are, it is stated, prone to give the workers cumulative fatigue, 

 dizziness, headaches, and impaired hearing. Even relatively minor 

 noises, such as that of an electric fan or vacuum cleaner, can be 

 extraordinarily irritating at times. It is only when the noise is 

 stopped that the pronounced sense of relief makes one realize that one 

 has been unconsciously bracing one's self against the noise all the 

 time. Some such reaction no doul^t occurs to noise during sleep, and 

 may perhaps contribute to the difficultj^ which some people have of 

 obtaining really refreshing sleep in a railway sleeping-car. 



In October, 1928, the British Medical Association submitted to the 

 Ministry of Health a valuable memorandum dealing with the effect 

 of noise on human beings. Their conclusions were in close accord- 

 ance with those arrived at by the New York Noise Coimnission, who 

 found that: 



(1) Hearing is apt to be impaired in those exposed to constant 

 loud noises. 



(2) Noise interferes seriously with the efficiency of the worker; it 

 lessens attention and makes concentration upon any task difficult. 



(3) In the attempt to overcome the effect of noise, great strain is 

 put upon the nervous system, leading to neurasthenic states. 



(4) Noise interferes seriously with sleep, even though in some 

 cases it appears that the system is able to adjust itself so that wake- 

 fulness does not result. 



(5) It is well established that the normal development of infants 

 and young children is hindered by constant loud noises. 



These conclusions are in general harmony with those of the Inter- 

 national Labor Office of the League of Nations, which in a recent 

 paper stressed the importance of the subject of the fatigue produced 

 by noise in relation to occupations. 



