This is an archival version of the original KnowledgePoint website.

Interactive features have been disabled and some pages and links have been removed.

Visit the new KnowledgePoint website at https://www.knowledgepoint.org.

 
0

Water Purification Tablets

RedR TSS
RedR TSS
KnowledgePointAdmin
RedR CCDRR

I am in need of rapid advice on chlorination tablets for simple water purification needs, in a post-cyclone situation, where the tabs will be given to our community contacts.

Please advise on how we may best procure the tablets before we leave or give any suggestions you may feel appropriate.


7 Answers

0
RedR TSS
RedR TSS

It depends what the real problem is...If people need to chlorinate water within the home, then take the tablets.

However if sources such as wells or piped water supplies can be rehabilitated I would be tempted to take a Delagua kit (Water testing kit from University of Surrey) instead of the tablets - Assuming someone is qualified to use it, or someone can be found, water sources could be tested and household bleach used for water purification, (assuming some can be found - check local sources to confirm). That way a water programme would be much more extensive.

Regards, Mark Buttle

0
RedR TSS
RedR TSS

Caution: I am not a doctor !!!!

It will depend on if you are prioritising your team or beneficiaries

For Small scale:

I am Cambodia based and our pharmacy routinely obtains from Thailand hydroclonazone 12.2 mg x 1000 tablet pack

1 tablet per litre takes about 1 hour to work, 2 hours for giardia and worst sorts. Seems to work OK and should be available

In Kenya for South Sudan we bought Micopur - 100 tabs per box - about 30 minutes for bacteria and 2 hour for giardia - very long shelf life - 1 tab per litre

Alternative is iodine - cheaper but definitely not tasty

....................................... For Emergency Chlorination / disinfection of community water supplies .................................................. WHO brief guide on emergency chlorination recommends potential chloride sources as... - Sodium Hypochlorite: liquid form e.g. typical chlorine based household disinfectant (5 to 15% available chlorine), laundry bleach (5%) or antiseptic "baby care" products (1 to 2 %). Avoid using scented disinfectants as this will taint the water - Calcium Hypoclorite: Available in granules known as High Test Hypochlorite, HTH with 60 to 70 percent available chlorine. The handbook notes the needs for "careful planning and coordination with local health posts and district health team" - bleaching powder or chlorinated lime (20 to 35 % available chlorine) Bleaching powder needs to be carefully mixed with a little water to make a cream paste stirring with a wooden rod. Then add more water to achieve a one percent solution - Water purification tablets. These usually contain 1 mg or chlorine or typically 2 mg of iodine. They are designed to treat 1 litre of clear water, but leave a taste. Most tablets have a shelf life and need to be stored in a cool dark place

NOTE STRONG CONCENTRATIONS OF CHLORINE ARE DANGEROUS

................................................................................. You might be well advised to think of Malaria -I am not sure of Myanmar risk but for provincial work in Cambodia we use doxycycline 100mg tabs which is readily available

Caution: - make sure you go to a good pharmacy, check how they store their stocks and check expiry date - is a lot of badly stored and out of date medicine around even in cities

Regards,

Chris Nixon

0
RedR TSS
RedR TSS

I would also go with water purification tablets but can not help with where to get these in a hurry. In terms of what type/strength, you should be clear on your purpose; water purification tablets come in widely varying strengths, from those meant for a single litre of water to those meant for use in contaminated wells. Taken orally or used incorrectly water purification tablets will do harm.

If possible get something people there would recognise and maybe already know how to use.

You should include information on how to use these in whatever languages are common to the area and graphically also if you can arrange this.

30 kg is not so much in terms of weight so nothing else seems worth carrying. If more space/weight could be got then I would suggest small collapsible water containers or bladders.

You might want to take advice from a doctor experienced in such emergency situations about the suitability of antibiotics.

Regards,

Paul Firwan

0
RedR TSS
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

0
RedR TSS
RedR TSS

There are a number of tablet products on the market that act as coagulants as well as providing disinfection. One of the difficulties in using chlorine and chlorine tablets is that the water must be free of organics (turbidity and suspended sediments). If this is not the case then the chlorine combines with the organics to form organo-chlorines, which will give the water a strong smell of bleach even at quite low concentrations of chlorines, rendering it unpalatable. The coagulants remove this problem. It is perhaps more appropriate, given your limited space, to consider finding a way to support disinfection by boiling once in country. This requires a jerry can, a pot and firewood, and the process will be known to the people you are working with. Cotton cloth (similar to the cloth in a t-shirt) makes a effective filter against suspended sediments and organics, and is economic if used with a screw top jerry can. See below for some links to suppliers and shippers of water purification tablets, you will have to contact them directly.

https://www.gripolabs.com/aqua_pura_water_purification_tablets.html

https://www.basegear.com/potable-aqua-chlorine-dioxide-tablets.html

https://www.aquatabs.ca/

https://www.quakekare.com/browseproducts/Water-Purification-Tablets.HTML

Regards,

Cody

0

Chlorine tablets- We provided chlorine tablets manufacturers and chlorine tablets suppliers in india. We are also chlorine tablets importers and chlorine tablets exporters in india. chlorine tablets dealers and chlorine tablets traders in india. buy chlorine tablets in india. Chlorine tablets