CHLORINE, 40mg, NaDCC 67mg, for 10l water disinfection, tab

Tablets of disinfectant (NaDCC Chlorine) used for treating small quantities of water with a turbidity of < 5 NTU.

NaDCC exists in 2 different chemical forms: anhydrous and dihydrate.

Often used for household water treatment.

Sodium dichloro-s-triazinetrione or sodium troclosene.

Water purification tablets containing 67 mg sodium dichloroisocyanurate (NaDCC) which releases 40 mg available chlorine.

Strength of solutions is expressed in terms of available chlorine content (either in g or mg per litre, in parts per million (ppm), or as a percentage).

=> 40 mg/litre = 40 ppm = 0.004%

This strength is intended only for disinfecting small quantities of drinking water.

Dissolve:

• One 40 mg tablet in 10 litres of clean water. Allow to react for at least 30 minutes before drinking.

The above dosing is recommended by the manufacturer. Actual chlorine demand might differ from water to water, especially when chlorinating surface water. It is highly recommended to carry out a jar test to define appropriate dosing.

Turbid water should first be brought to a turbidity of <5 NTU before being treated with chlorine. To reduce turbidity, turbid water should be filtered, clarified or allowed to settle.

For large-scale water treatment, NaDCC or calcium hypochlorite granules (HTH).

See "Public Health Engineering in Precarious Situations", MSF, 2nd edition 2010:

• T.B. 2.19 Chlorine-generating products
• T.B. 2.20 Preparation and use of chlorine solutions for disinfection
• T.B. 2.21 Batch chlorination of drinking water
• T.B. 2.22 Monitoring chlorination

Read the household water treatment hand book (MSF2015) T.B. (Technical Briefs) chapters 1 and 2 before starting.

T.B. chapter 1 describes the pre-test to be performed before the distribution as it will indicate whether the full treatment (pre-treatment + disinfection) is required and if both chemical consumables must be distributed.

To ensure appropriation of the kit and use of treatment it is essential to combine distribution and demonstration and use sensitisation tools. Follow the distribution procedure described in T.B. chapter 4.

See as well "Public Health Engineering in Precarious Situations", MSF, 2nd edition, 2010:

• T.B. 2.20 Preparation and use of chlorine solutions for disinfection

Remark

Use a pool-tester to check the presence of free residual chlorine.

See "Public Health Engineering in Precarious Situations", MSF, 2nd edition, 2010:

• T.B. 2.22 Monitoring chlorination