Accidents in sewers : report on the precautions necessary for the safety of persons entering sewers and sewage tanks.
- Great Britain. Committee on Accidents in Sewers.
- Date:
- 1934
Licence: Public Domain Mark
Credit: Accidents in sewers : report on the precautions necessary for the safety of persons entering sewers and sewage tanks. Source: Wellcome Collection.
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![which, as mentioned above, arise from the decomposition of sewage solids in sewers, and in the absence of precautions there is grave risk of asphyxiation, explosion, or poisoning wherever these gases collect. Asphyxiation 18. Only by adequate ventilation can irrespirable gases be removed from the sewer or sewage tank and the danger of asphyxiation obviated. To this end sewers should be laid with a self-cleansing gradient and with a sufficient number of manholes to ensure adequate ventilation. Tanks should where possible be open to the air, an arrangement which wil! not only assist ventilation but also facilitate access and egress. Explosion 19. It has been impressed upon us that the admission of petrol into the sewers is highly dangerous, and that there should be the greatest strictness in guarding against its admission. We have been fortunate in this country in that there has been no very serious accident due to petrol in sewers, but the experience abroad, particularly in Canada and the United States, shows that most devastating accidents may occur through petrol. Petrol is transported by road in bulk, and in the event of the tank wagon springing a leak through collision or other cause, the overflowing petrol will generally find its way along the gutters of the roadway into the sewers. it is, of course, impossible to provide against pure accidents, and the existing regulations concerning the construction of tank wagons are considered by. the Home Office to be satisfactory. All that can be done is to suggest that whenever possible (though we fear this would be rare), the petrol should be emptied from the damaged tank on to waste ground, if an accident should occur. In the event of a large quantity of petrol being thrown into the roadway, either the police or the fire brigade should be in a position to inform the sewer authority in order that any men working in sewers likely to be affected by the intake of petrol] may be withdrawn. No men, of course, should be allowed to enter any affected sewer until it had been determined that the petrol vapour had been finally dispersed. Petrol might enter sewers from garages. So far as the private garage is concerned, there is general agreement that little or no danger of petrol entering sewers arises. Any small quantities of petro! spilt in a small garage would be likely to evaporate before it reached a drain. Larger garages, for example repair garages having workshops attached, fall within a different category. There, larger quantities of petrol are handled. and the risk of material quantities of petrol reaching the sewers is increased, but under the general law special precautions have been taken to prevent it. The use of petrol or similar liquids for cleaning purposes in private houses is growing and the practice which no doubt prevails of disposing of the petrol into drains cannot be too strongly deprecated. In this connection we think it may be useful to quote the following remarks in the Report of H.M. Inspector of Explosives for 1932 :— “Petrol should never be exposed except to the minutest extent in the house, and it must never be thrown down a drain or sink ... by so doing a fatal explosion may result in a drain or sewer. Waste petrol should be disposed of on open ground which for a time must be regarded as a danger zone ” Poisoning 20. Our evidence clearly points to this danger, particularly from sulphuretted hydrogen, being the gravest encountered in sewers and sewage tanks. The danger of the accumulation of the gases will correspond with](https://iiif.wellcomecollection.org/image/b32181516_0006.jp2/full/800%2C/0/default.jpg)
