NSF International / American National Standards Institute
NSF/ANSI drinking water treatment unit standards
The certification standards for point-of-use and point-of-entry water treatment devices: NSF/ANSI 42 for aesthetic effects, 53 for health effects, 58 for reverse osmosis, 44 for softeners, 55 for ultraviolet, and 401 for emerging contaminants.
Rights
- Licence
- Publisher terms — public access, reuse not clearly granted
- Commercial reuse
- Not clearly stated
- Redistribution
- No
- Derivative use
- Not clearly stated
- Attribution required
- YesData from NSF International / American National Standards Institute, used under Publisher terms — public access, reuse not clearly granted.
- Restrictions
- The standards themselves are copyrighted and sold. The certification listings, which record what a given product is certified to reduce, are publicly searchable.
- Terms last checked
- 23 August 2026
Access and coverage
- Publisher
- NSF International / American National Standards Institute
- Website
- https://www.nsf.org/
- Geographic coverage
- International — primarily North America
- Update frequency
- irregular
- Formats
- html
- Bulk download
- Not available
- Registration required
- No
- Cost to Hydrionis
- Free
- Domains
- quality, contaminant
Notes
The certification listing is the load-bearing fact: a filter "meeting NSF 53" is meaningless unless it is certified for the specific contaminant claimed. Hydrionis states the contaminant-specific certification wherever filtration effectiveness is discussed.