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EPA Region 6 State Drinking Water Laboratory Certification

Laboratories that analyze samples of drinking water are required by EPA to be certified by an approved certifying authority.  The Region 6 laboratory certification officers conduct on-site evaluations of laboratories operated by states.

The Drinking Water Laboratory Certification Coordinator audits the states’ certification program to ensure that all laboratories analyzing drinking water samples are following approved methods as mandated by EPA’s National Primary Drinking Water Regulations.  This ensures the public that their drinking water is free from harmful contaminants.

Although the certifying authority for private and municipal laboratories lies with the state, the Region 6 laboratory certifying officers are always available to provide technical assistance whenever needed. For additional information, contact Marvelyn Humphrey (, Laboratory Support and External Oversight Section Chief , or Ray Clark (, Drinking Water Laboratory Certification Coordinator.