An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Environmental Measurements and Modeling

Internal Measurement Competency Documents

To assure the quality of our data, all laboratories operated by EPA, including contractor operated facilities need to maintain a documented Quality System. At a minimum, the system must comply with the requirements of the EPA Quality System as defined by CIO 2105.0 May 2000, Policy and Program Requirements for the Mandatory Agency-wide Quality System. This policy is listed below and contains the specific requirements.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.