1.1 This test method covers a procedure to test membrane filters for their ability to retain bacteria whose diameter is equal to or slightly larger than membrane filters with pore size rated at 0.40 to 0.45 µm.

1.2 The procedures described are for the use of user laboratories as differentiated from manufacturers' laboratories.

1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.