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Trichloroisocyanuric Acid (TCCA) for drinking water chlorination


Access to common chlorine generating products (HTH, NaDCC) is limited in Iraq and other Middle-Eastern contexts. Trichloroisocyanuric Acid (TCCA) is available however, marketed for use in swimming pools as 'clean pool 90'. The tablets are 200g, with available chlorine listed as 90% minimum. The dosage would need to be reduced considerably for, say a 10m3 water truck.

My main concern, however, is whether this would be a suitable chemical for the chlorination of drinking water? To an untrained eye it looks similar to the Sodium dichloroisocyanurate (NaDCC) used in Aquatabs, but I'm unsure whether any of the bi-products might be hazardous in drinking water.

As a slow release tablet the proposal would be to use this in a floating pot chlorinator.

Any guidance would be very much appreciated.

4 Answers

Martin Currie _ Aqueum

Trichloroisocyanuric Acid products by Allchem, Clearon, GE, Medentech, Occidental and Shikoku appear to be listed as NSF certified drinking water chemicals under NSF/ANSI 60 (

That of course doesn't say much about "Clean Pool 90". I personally wouldn't use any proprietary chemical that wasn't specifically intended for drinking water treatment & certified by a competent and relevant authority as such. Even if pure TCCA is an acceptable disinfectant, you need to ask what fillers, stabilisers and other chemicals are included in "Clean Pool 90". There is also a possibility that their TCCA production process could result in inappropriate byproducts. The formulation for a chemical intended for pool water use is likely to be much less stringent than for one intended for direct human consumption.

I think the certification of these other TCCA's under NSF/ANSI 60, and the size of your potential market hopefully will give the manufacturers of "Clean Pool 90" or other TCCA's available to you sufficient motivation to go for some form of potable water certification if they do believe their product is wholesome.


Many thanks, Martin, for your answer - the link to the NSF60 product listing is especially useful. The list of certified products has been shared now with procurement teams from several agencies in the hope that we will be able to find a product available in Iraq suitable for bulk water treatment.

JBrown gravatar imageJBrown ( 2016-04-21 17:00:32 )

There are TCCA tablets for drinking water chlorination, which are extensively used in emergencies:


Thanks for your answer - however my understanding is that Oasis tablets are Sodium Dichloroisocyanurate (Troclosene Sodium / NaDCC) rather than Trichloroisocyanuric Acid (TCCA). Does anyone have experience using TCCA for treatment of drinking water?

JBrown gravatar imageJBrown ( 2016-04-11 09:40:04 )

Hi. Dichlor and Trichlor have very similar chemical structures and are therefore both used in disinfection of water, whether that be pools, drinking water etc. The by-products formed by both will be the same as it's not the source of the chlorine that are the problem with DBP, but what the chlorine reacts with once it's dissolved in the water. Both dichlor and trichlor dissociate quickly in water (to form hypochlorous acid/hypochlorite and cyanuric acid). If you want a slower release chlorine tablet, a tablet based on calcium hypochlorite is a better option.


Could anyone comment if it is appropriate to use TCCA tablets in potable drinking water