Noise from the Use of Rock Drills in Street Works.
The Council on the 20th July, 1933, referred the question of noise caused by the use of rock drills in street works to the Works and Public Health, &c., Committees for consideration and report. The Medical Officer of Health reported upon the subject to the Committees concerned and as the matter is of public interest his report is fully set out:— The Use of Rock Drills in Street Works and the Effect of their Noise on the Health of the People.
1. This matter is part of a reference from the Council at its meeting on 20th July last. The whole reference was made to the Works Committee which was instructed to consult with the Public Health Committee as to the aspect outlined at the head of this report. It is now understood that the Works Committee wish to be favoured with the views of the Public Health Committee.
2. It is unfortunately true that increasing noise seems to be a natural accompaniment of changing conditions particularly in cities and towns, but even in rural areas murmurs of complaint are being heard because of the motor traffic which rends the silence of the night. During the past few months The Times newspaper has given liberal opportunity for expression of opinion on the harmful effects of noise on health and from many authoritative quarters has come an appeal to mitigate or to prevent this menace. Thus has arisen a definite movement of public opinion now organised in a society called the Anti-Noise League, which numbers among its members many distinguished men and women including leading physicians and surgeons.
3. So far as can be gathered the activities of this League are directed against such noises as arise from motor vehicles, the handling of milk churns, church bells and others more or less of a chronic character. Very little attention has been given to the much more acute and violent noise from rock drills which is necessarily periodic, but constant during the operation of these implements.
4. With regard to interference with health one should first examine the question as it affects work and rest. The interference is so obvious that it needs but little elaboration. Mental concentration, discussion and the normal transaction of business is almost impossible within 20 yards of these drills and of course the evil is magnified according to the number being operated. It has been alleged that loss of business has been experienced in shops and similar premises adjacent. In a neighbourhood of mixed business and residential buildings the factions struggle for privilege. The non-residents would prefer the drilling to proceed only at night while the residents indignantly retort that their sleep has the prior claim for respect. There can be little doubt that the over stimulation of the auditory sense organs leads to nervous exhaustion and impaired efficiency.
5. Interference with rest and sleep is of a more serious nature as an average healthy individual cannot work to the best advantage unless he obtains sufficient rest and sleep. If road drilling is carried on late at night or early in the morning near dwellings the residents arc bound to suffer. Those who are fortunate enough to be masters of their own time arrange to go on holiday or otherwise temporarily leave the district until road operations are over. For those who must remain at home this period is trying in the extreme. Usually road drilling docs not last longer than a week or two, but in special circumstances it may persist for months. During the recent summer in a certain street in Westminster, drilling continued every day except on Sundays and with two or three days of peace occasionally intervening from early in July until well into September; a series of small areas of the roadway were being explored. For those who are confined to their houses by illness, conditions are of course definitely serious. It requires but little imagination to appreciate that the recovery of a case of acute or serious illness might be jeopardised by the deprivation of rest and sleep and the exhaustion caused by constant vibratory noise.
6. During September the Medical Officer of Health took steps to investigate conditions at Westminster Hospital while street excavation was in progress. The Secretary of the Hospital hastened to assure the Medical Officer that the City Council had been most considerate of the interests of the Hospital and in consequence the latter did not wish to make any complaints. It was explained that it would be helpful if an unbiased statement on the effects of the noise then in progress could be obtained. The following is an extract from the report kindly supplied by the Resident Medical Officer dated 13th September, 1933:— ” At least half of the Hospital was practically sleepless for nights at a time. The chief sufferers were naturally those about to be operated upon and those whose operations had just been performed. At least two eases awaiting thyroidectomy suffered acutely, whilst the many cases of head injuries in the Casualty Ward were to be profoundly pitied. In fact, hospital treatment, medical and surgical, has been seriously interfered with. On one occasion a private patient insisted upon leaving the Hospital owing to the disturbance. Apart from the patients, I found the resident medical officers suffered considerably. As far as my own duties were concerned, my whole days and nights for about three weeks were never free from the noise of hammering, and I was constantly up at night trying to make things bearable. Please do not think I am making unnecessary complaints, but six automatic drills working in a line for hours at a time, filling the Surgery, the Wards, and the Resident Medical Officer’s Rooms with dust, has rendered life extremely unpleasant.” It will be noted that in addition to noise, dust is alluded to as a cause of nuisance.
7. The Medical Officer has consulted the Department of Scientific and Industrial Research and the London School of Tropical Medicine and Hygiene as to the results of any investigations of the effects of rock drills on health. The former body is not concerned with health but expressed willingness to take up the question of research into the maintenance of roads and methods of repairs, &c.
8. The London School of Tropical Medicine and Hygiene has been keenly interested on the health aspect for some considerable time. Dr. Crowden, a member of the staff, has been working on the subject and has different types of these drills fitted up in his Laboratory with the stone and concrete medium in which they operate. His conclusions so far are briefly as follows:— (1) Among riveters and boilermakers incurable deafness develops in the course of time. A large proportion of the men arc affected and it is due to the concussions of sound and sudden changes of air pressure incidental to riveting in an enclosed space, e.g., between decks in a shipyard. Road drillers on the other hand work in the open and apparently are not subject to deafness. (2) Riveters and boilermakers suffer from the effects of vibration on their hands ; a chronic numbness is caused due to interference with the circulation. These effects were largely dependent on cold; coldness of the atmosphere and of the handles of the apparatus. In the ease of road workers the air conducted to the drills is conveyed in comparatively short pipes and is, therefore, not cooled in long transit. The handles are not cold and these road workers do not suffer from the disturbance of circulation mentioned above. Dr. Crowden has not yet investigated the medical records of hospitals to see whether there are any grounds for assuming that complaints of nervous or other diseases arc based on the occupation under discussion. 9. It is most important to observe that the workers themselves do not receive the main impact of the noise as the sound and percussion waves intensify as they impinge on any high stone buildings surrounding.
10. In his enquiries he found that the men greatly preferred the mechanical drills to the hand pick and hammer. In one. instance a body of men threatened to strike because they were asked to go back to the methods of using human energy. Several firms reported that with manual excavation their casualty rate increased noticeably; chipped hands, fragments lodging in the eyes and other injuries were not uncommon. That was the main reason for the men’s preference for the mechanical drills.
11. The use of silencers diminishes the intensity of vibration but also lessens the efficiency of the instrument. Therefore, in order to complete certain work within a given time it would require additional partially silenced drills for every single unsilenced one. More men would be required and the net result would prove of no advantage because those extra drills would cause quite as much noise as a single unsilenced drill.
12. Dr. Crowden has studied the methods of ear stopping used among gun crews in the Navy, and in shipyards and other industries, and showed various types with which he had experimented. One of the most efficient and certainly the cheapest is shown to the Committee. They ought to be distributed among those who are about to be subjected to the noise of road drilling in their close vicinity.
13. In December, 1929, the Medical Officer of Health reported on the prevention of noise in connection with a presentment from the Metropolitan Standing Joint Committee. Although the matter under present consideration is limited to ” rock drills,” yet it may be interesting to recall that no fewer than seven different sources of noise were enumerated on that occasion as being causes of complaint to the Public Health Department. He commented on the fact that the By-laws made by the City Council from time to time to control different types of noise nuisance had been of great public benefit; and the London County Council had also made by-laws for other sources of noise which had also been effective.
14. Since those days other and no less obnoxious noises have arisen and some local authorities, notably Edinburgh, have sought powers to prohibit certain noires. There is no doubt that sooner or later public opinion will demand some measure of relief from this growing nuisance. Summary. The noise caused by the use of rock drills :— (1) Interferes with the work, occupations, or other activities of those in close proximity to the scene of their operations. (2) Is definitely harmful to the sick and may even jeopardise the lives of those suffering from acute or dangerous illness. (3) Disturbs the rest and sleep of those living nearby and is in consequence prejudicial to, and in some cases, injurious to health. (4) Under existing conditions, and so far as can be ascertained at present, is not prejudicial to the health of those operating these instruments. (5) Usually lasts in any given locality but for a limited period say one or two weeks and this is an important point in mitigation. (6) Is preferred by the workers to hand driven methods of operation. (7) Is somewhat diminished by fitting silencers, but to make up for the resulting loss of efficiency more drills must be employed. (8) Can be lessened in intensity for the sufferers if they use ear stops. These could be distributed among patients and other susceptible individuals. (9) Is only one among the many which are causing much concern. A public movement has been organised to combat this menace to health and quietude. The Committee might sec fit to express an opinion that although the noise caused by the use of rock drills in street works may arise in any given locality for a period of only a few days and may not recur for several years, yet there is evidence that health may be injuriously affected thereby and requests the Works Committee to consider what steps should be taken to effect its diminution. The Council received the report of the Committees on the 14th December and resolved that representations be made to the appropriate Government Departments with a view to special research being undertaken for the reduction of noise caused by the use of rock drills in street works.