Oct 20, 2022

Most Probable Number Demo

The most probable number (MPN) test method estimates the number of indicator bacteria that is most likely present in a water sample. This demo will show how to conduct a MPN test using a Hach Pathoscreen Test Kit.

Multiple samples (1-10 mL) of the same water to be tested are added to a culture media in sterile tubes and incubated at a particular temperature for a fixed time (usually 24 hours). By counting the number of tubes showing a positive result and comparing with a standard table, a statistical estimate of the most probable number of bacteria can be made. The results are reported as MPN 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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