Mar 28, 2023

Testing for Microbiological Aspects Technical Brief (DWQT)

Testing for every possible pathogen in water would be time consuming, complicated and expensive. You can test for indicator organisms as a way of assessing the microbiological safety of drinking water. Escherichia coli (E. coli) and thermotolerant coliforms are often used as indicator organisms for fecal pathogens. When these microorganisms are present in water, fecal contamination is likely. This brief describes three main test methods to detect the presence of indicator bacteria in drinking water: Presence-Absence (P-A), Most Probable Number (MPN), and Membrane Filtration (MF).

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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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