prEN ISO 7899-3

Water quality - Enumeration of intestinal enterococci - Part 3: Most probable number method (ISO/DIS 7899‑3:2024) prEN ISO 7899-3

General information

30.99 CD approved for registration as DIS   Apr 3, 2024

CEN

CEN/TC 230 Water analysis

European Norm

Scope

This document specifies a method for the enumeration of intestinal enterococci in water. The method is based on the growth of target organisms in a liquid medium and calculation of the “Most Probable Number” (MPN) of microorganisms by reference to MPN tables or using informatic programs.

The test described in this document relies upon the detection of intestinal enterococci based upon expression of the enzyme ß-D-glucosidase. This method provides a confirmed result in 24 h with no requirement for confirmation of positive wells.

This method can be applied to a range of types of water (for example, drinking water, bathing water, groundwater, surface water and wastewater), including those containing an appreciable amount of suspended matter and high background counts of heterotrophic bacteria.

For marine waters, enterococci are best enumerated using diluted samples.

Life cycle

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IN_DEVELOPMENT
prEN ISO 7899-3
30.99 CD approved for registration as DIS
Apr 3, 2024