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[[Image:safe_water_systems_icon.png|right|80px]][[Image:NaDCC, also known as sodium dichloroisocyanurate or sodium troclosene, is one form of chlorine used for disinfection. It is often used to treat water in emergencies, and is now widely available for household water treatment. jpg|thumb|right|200px|NaDCC tablet]]
NaDCC, also known as Sodium Dichloroisocyanurate or Troclosene Sodium, is one form of chlorine used for disinfection. It is often used to treat water in emergencies, and is now widely available for household water treatment. NaDCC tablets are available with different chlorine content (e.g. 3.5 mg to 10 g) to treat from 1 to 3000 litres at a time. They are usually effervescent (meaning that escaping carbondioxide carbon dioxide gas causes the tablets to dissolve quickly, with a 'fizz'), allowing the tablet to dissolve in less than 1 minute.
When added to water, NaDCC releases hydrochloric acid which reacts through oxidization with microorganisms and kills them.
Chlorine began to be widely used as a disinfectant in the early 1900’s. It revolutionized drinking water treatment and dramatically reduced the incidence of waterborne diseases. Chlorine remains the most widely used chemical for water disinfection in the United States.
===Suitable conditions ===
Unlimited amounts of water can be processed at a time, depending on the amount of active chlorine.
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===Construction, operations and maintenance===[[Image:chlorine tablet WHO.jpg|thumb|right|250px200px|Domestic chlorination using a chlorine tablet. Photo: WHO.]]
Each product should have its own instructions for correct dosing. In general, the user adds the correct sized tablet for the amount of water to be treated, following the product instructions. Then they agitate the container, and wait for the amount of time instructed on the package, normally 30 minutes (“contact time”). The water is then disinfected and ready to be used.
Most users cannot determine the dosing quantity themselves; proper use requires simple instructions from the manufacturer. Users often use less than the recommended dose to save money.
Metering pumps as [[Dosatron]] can be used to perform proportional dosing
====Manufacturing====
====Treatment Efficiency====
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====Suppliers====
Hydrachem Ltd. manufactured Oasis [http://www.oasiswaterpurification.com/ Water Purification tablets] in the United Kingdom. Hydrachem are the largest suppliers to UNICEF.<ref name=unicef14>[[#unicef14|UNICEF Supply Report (2014)]]</ref>
Medentech Ltd. manufactures Aquatabs for water disinfection, hospital surface infection control and general environmental disinfection. In Tanzania, PSI imported a single sized 20 litre-tablet that are packed locally in boxes of 36 10 tablet-strips.
===Costs===
{{Treatment_Cost
|CapCost=US$ 0
Note: Program, transportation and education costs are not included.
==Field experiences== ==Reference manualsManuals, videos, and links===* [http://fieldresearch.msf.org/msf/bitstream/10144/618835/1/FRC+Op+Guidance+Briefing+Note+%28Nov+2016%29.pdf Operational Guidance Briefing Note: Evidence-based Free Residual Chlorine (FRC) Targets]* [http://www.hydrachem.co.uk Hydrachem Ltd.]
* [http://www.cawst.org CAWST (Centre for Affordable Water and Sanitation Technology)]
* [http://www.aquatabs.com Aquatabs]
* [http://www.medentech.com Medentech Ltd.]
==Footnotes=References===
<references/>
===Acknowledgements===
This article is based on a factsheet from [http://www.cawst.org/ Centre for Affordable Water and Sanitation Technology (CAWST)], which is gratefully acknowledged.