World Health Organization: Presence–Absence Test for Total Coliform Bacteria Mobile App
The safe quality of water supplied to communities is an important consideration in the protection of human health and well-being, it is not the only factor that affects consumers.
How does it work?
When water samples are collected for analysis, care should be taken to ensure that there is no external contamination of the samples. Unless valid samples are collected, the results of the subsequent analysis may be misleading. The World Health Organization: Presence–Absence Test for Total Coliform Bacteria mobile app provides a detailed list for the Presence–Absence Test for Total Coliform Bacteria.
Presence–absence tests may sometimes be appropriate where positive results are known to be rare. They are not quantitative and, as their name suggests, they indicate only the presence or absence of the indicator sought. Such results are of little use in countries or situations where contamination is common and the purpose of the analysis is then to determine the degree of contamination rather than simply to indicate its presence.