Learn about Drinking Water Analytical Methods
- What are analytical methods?
- Who develops methods?
- How does EPA approve methods?
- How does EPA evaluate methods developed by others?
- Who uses the methods?
- How can I get involved?
What are analytical methods?
Analytical methods are procedures used to measure the amount of particular contaminants in water samples.
Analytical methods generally describe how to:
- Collect, preserve, and store the sample
- Gather, separate, identify, and measure contaminants in the sample
- Meet quality control criteria
- Report the results of the analysis
In general, an analytical method:
- Applies to routine analyses of samples
- Measures the drinking water contaminant(s) within a specific upper and lower limit
- Provides data that are required to:
- Demonstrate compliance, or
- Meet monitoring objectives in a wide variety of drinking water conditions
- Incorporates appropriate quality control criteria so that acceptable method performance is demonstrated during sample analysis
Who develops methods?
Methods are developed by:
- EPA or other governmental organizations
- Consensus method organizations such as Standard Methods and ASTM, International
- Universities
- Water laboratories
- Commercial vendors
How does EPA evaluate methods developed by others?
EPA uses the Alternate Test Procedure Program to evaluate analytical methods from a variety of sources.
How does EPA approve methods?
EPA approves methods:
- When regulating new contaminants or through other rulemaking actions
- Using the expedited approval process
Who uses the methods?
Laboratories supporting public water systems must use EPA-approved analytical methods when analyzing samples to demonstrate compliance with drinking water regulations
How can I get involved?
Request for Public Input on Methods – April 2024
EPA requested public input on drinking water analytical methods for emerging contaminants in drinking water, particularly those listed on the agency’s Fifth Contaminant Candidate List (CCL 5). The Federal Register Notice (FRN) described published drinking water analytical methods and EPA drinking water methods in development for the CCL and other emerging contaminants. EPA invited public input on drinking water analytical methods through April 8, 2024. Please refer to the FRN notice to view submitted comments.
40 CFR (Code of Federal Regulations, Title 40) Part 141 - Notice of Method Request (pdf) (432K)
Methods in Development – June 2018
EPA hosted a public meeting and webinar in June 2018 at the Andrew W. Breidenbach Environmental Research Center in Cincinnati, OH. The meeting continued the open discussion with stakeholders and was designed to spark innovation on analytical testing procedures for unregulated contaminants in drinking water.