Data on the composition and characteristics of water are frequently used to evaluate the health and safety to humans and the environment.

Moreover, such data are frequently used for process control or to ascertain compliance with regulatory statutes that place limits on acceptable compositions and characteristics of waters.

Laboratories that conduct water sampling and generate analytical data, and those persons who have the responsibility for selecting a laboratory to perform water quality studies, need to use criteria, guidelines, and recommendations that have been developed by consensus and are well accepted in making this selection.

Demonstration and documentation by a laboratory that there was judicious selection and control of organization, facilities, resources, and operations will enhance the credibility of the data produced and promote its acceptance.

1.1 This guide provides information on consensus good laboratory practices for laboratories that provide services in the sampling and analysis of water. As consensus standards, these are the minimum criteria that all laboratories should consider in establishing their good laboratory practices.

1.2 This guide is designed to be used by those responsible for the selection, operation, or control of laboratory organizations engaged in sampling and analysis of water.

1.3 This guide presents features of organization, facilities, resources, and operations which affect the usefulness of the data generated.

1.4 This guide presents criteria for selection and control of the features described in and also makes recommendations for the correction of unacceptable performance.

1.5 This guide describes methodology and practices intended to be completely consistent with the International Organization for Standardization (ISO) 9000 series of standards and Guide 25 - 1990 ().

1.6 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

This standard does not purport to address all of the safety concerns, 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.