Mar 13, 2023

Learn About Chlorine

Learn About Chlorine


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Dec 1, 2021

Check Before you Disinfect: Batch Chlorination Scenario

Turbidity, pH, and temperature can all impact how fast and how well chlorine products can disinfect drinking water. Challenge yourself as you manage a water delivery at a humanitarian camp; select and evaluate the required water parameter tests and learn how these parameters can affect chlorine dosage and contact time.


Nov 30, 2021

Using the Modified Horrocks' Test to Calculate effective Chlorine Dosage

The Modified Horrocks' Test is a method of calculating the correct chlorine dosage for a known quantity of water. Follow along with Peter Thomson, senior director at CAWST as he conducts the Horrcks' test to calculate the correct chlorine dosage for a batch of drinking water.


Aug 18, 2021

Free Residual Chlorine - What Does it Mean?

Are you confused about the difference between free residual, combined and consumed chlorine in drinking water? We can help.


Aug 16, 2021

What's Happening with the Chlorine Levels?

This microlearning tool helps you discover potential problems when testing pH and chlorine in the field using a pooltester kit.


Jun 21, 2022

How to use a pool test kit

This tool teaches you step-by-step how to use a pool test kit to measure pH, free chlorine and total chlorine. It also includes troubleshooting tips.


Jun 21, 2022

Chemical Testing Methods

Learn to identify and compare different chemical test methods.


CAWST is a Canadian charity and licensed engineering firm. We address the global need for safe drinking water and sanitation by building local knowledge and skills on household solutions people can implement themselves.

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Development of this website and creation of collections of emergency themed tools on Water Treatment, Water Quality Testing, Behavior Change and Sanitation funded by Bureau of Humanitarian Assistance - USAID.

This project is made possible by the generous support of the American people through the United States Agency for International Development (USAID). The contents are the responsibility of CAWST (Centre for Affordable Water and Sanitation Technology) and do not necessarily reflect the views of USAID or the United States Government.

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