Learn about Drinking Water Analytical Methods
- What are Analytical Methods?
- Who Develops Methods?
- How does EPA Approve Methods?
- Who Uses the Methods?
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?
EPA uses the Alternate Test Procedure Program to evaluate analytical methods from a variety of sources.
Methods are developed by:
- EPA or other governmental organizations
- Consensus method organizations such as Standard Methods and ASTM, International
- Water laboratories
- Commercial vendors
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:
- Meet federal monitoring requirements
- Demonstrate compliance with drinking water regulations