Oct 20, 2022

Membrane Filtration Demo

Membrane filtration (MF) is the most accurate method to determine the number of indicator bacteria in a water sample and is internationally recognized as a standard method for water quality testing. Membrane filtration can be done in a laboratory or by using a portable test kit as demonstrated in this video.

In general, a 100 mL water sample is filtered through filter paper using a small hand pump. After filtration, the filter paper is placed in a Petri dish with a nutrient solution and incubated at a specific temperature and time. After incubation, the bacteria colonies are counted to determine the number of colony forming units (CFU) per 100 mL.

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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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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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