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RedR TSS

Chlorine comes in a variety of strengths ranging from ordinary household liquid bleach up through tablets and HTH powder to chlorine gas which is used in advanced water treatment plants. Both the liquid and the gas are out as far as transport is concerned and gas is not easy to use. You would do better with the tablets or the HTH (High Test Hypochlorite) powder.

Liquid bleach may be available locally.

Probably the quickest to procure and easiest to use would be chlorine tablets available from good camping shops. They do (or used to do) small ones for 1 litre or larger ones for 20 litre containers. You could get a lot of such tablets in 30kg, though probably nowhere near the needs in country. One shop would be unlikely to carry that much stock but might be able to put you in touch with a wholesaler where you could get more at a lower price.

HTH powder would be slightly more difficult to use but I think that instructions for dilution are available in an appendix to Engineering in Emergencies. I buy it regularly for my swimming pool .

Both tablets and swimming pool supplies might be available from companies on the Internet.

Remember that it is uses less chlorine if you can get any silt out of the water before you add chlorine (by filtration or sedimentation). Water should be left standing for at least half an hour contact time to allow disinfection after chlorination. If you do not have testing equipment (e.g. Del Agua kit or a simple optical comparator for chlorine) a rule of thumb would be that if you can just taste chlorine in the water it is enough. People do not like to drink water with a very strong chlorine taste.

Hope this helps. Martin Ager