Withstanding the Tests of Time: The Value of Annual Testing
Why ongoing testing matters for NSF/ANSI/CAN 61 certified products.

NSF requires periodic retesting for all products certified to NSF/ANSI/CAN 61. For most product types, this testing occurs annually for as long as the product remains certified. Some categories—such as faucets, faucet components, and certain coatings—are tested every three or five years. Because these cycles vary by product type, this process is often called monitor testing.
Why repeat testing Is critical
Initial qualification testing confirms compliance with the health and safety requirements of NSF/ANSI/CAN 61. However, every year, about 15% of products fail qualification testing, proving that not all products maintain the quality needed to meet stringent health standards over time.
Even when manufacturers keep the same formulation for years, NSF’s extensive monitor testing data shows performance can change year over year. Certain categories—such as coatings and barrier materials—have higher failure rates due to factors like:
- High solvent concentrations
- Reactive components that polymerize during application
- Variations in solvent evaporation or reaction rates in multi-component coatings.
These variables increase the risk of noncompliance, making ongoing testing essential for protecting public health.
Annual testing isn’t just a requirement—it’s your assurance that certified products continue to meet the highest standards for safety and performance.
Learn more about NSF/ANSI/CAN 61 testing and certification
This standard sets benchmarks for evaluating water distribution products and materials. Learn about why it's required and accepted around the world.
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