This document specifies the requirements for the performance testing of membrane filters used for the retention followed by direct enumeration of microorganisms by culture methods.


This document is applicable to membrane filters which are used for retention followed by direct enumeration of specific microorganisms on solid media or on other devices containing media, like absorbent pads[19].


This document is not applicable for membrane filters used for concentration and elution or for qualitative methods.


These tests are applicable to the membrane filters intended for the microbiological analysis of different types of water, such as:


—    drinking water, bottled water and other types of water with expected low numbers of microorganisms;