Notes for sanitary officers, British Expeditionary Force in France / [the War Office?].

Date:
1917
Catalogue details

Licence: Public Domain Mark

Credit: Notes for sanitary officers, British Expeditionary Force in France / [the War Office?]. Source: Wellcome Collection.

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    (iv) Continue filling the cart with water and watch the colour in the cups until the cart is filled. If the colour in the cup next in the series disappears before the cart is filled, add at once one measure of chloride of lime made into a paste, and so on until half an hour has elapsed. The water will then be fit for use, but it is better to allow the chlorine to act as long as possible. Note.—lf the test has been satisfactorily carried out, water drawn from the body of the cart at the end of half an hour and placed in one of the cups previously washed out should give a blue or violet colour when three drops of the test solution are added to the water. The water in the body of the cart should always be examined n this manner whether the directions under A. or B. are being carried out. 24. Usk oF THE APPARATUS IN’ CONNECTION WITH WATER Carts, Marxs 11 D., IV. ann V. These carts are provided with a special clarifying apparatus, which should remove all suspended matter from the water. . In those circumstances it is usually found that one part per million of free chlorine will destroy in half an hour the bacteria causing water-borne disease. To make sure that free chlorine is present, clarified water from the cart as soon as it is filled should be placed in one of the cups and three drops of the test solution (zine iodide and starch) added. If a blue or violet colour is produced, the chlorination may be considered satisfactory. If the water remains colourless then the pro- cedure described in A. (i), (41), (aii), (iv) and (v) should be followed, the water being allowed to stand as long as possible after chlorination. 25. These test cases designated ‘‘ Cases water testing. sterilisation,’ are a Medical Supply and are issued on the following scale : — Units having a Medical Officer and BESonsee with a water cart ; piee sel Sanitary Section ... ie one tf A meek Field Ambulance ... 2 26. In some large areas the matic aes aoe ee been of doubtful purity, and by arrangement with the Civil Authorities continuous chlorination at the source has been instituted. Various automatic chlorinating plants are in use. In these the chlorine may be added in the form of bleaching powder, chlorine gas, or ‘‘ eau de javelle.”’ 297. DESCRIPTION OF AN AUTOMATIC CHILORINATING PLANT SUITABLE FOR SMALL Towns. The following description applies to a plant installed at a pumping station, having two pumps (each delivering 2,406 18080 B