Updated September 30, 2026
What is NSF/ANSI standards?
In short
NSF/ANSI standards are the tested contaminant-reduction claims a water filter carries, and the number on the listing shows which one.
NSF/ANSI standards are the certification marks water filters carry to show what a product has been tested to reduce, so the number tells you what is covered. Aquasana's certified products list 42, 53 and 58, the broadest set in this group, while aigerri lists 58 and APEC Water lists 58. Trade-off: a listing covers only the claims it names, so check the standard against the contaminant you actually care about.
Sources
- aigerri.com, checked September 30, 2026
- apecwater.com, checked September 30, 2026
- aquasana.com, checked September 30, 2026