NSF/ANSI 177 — Shower Filtration Systems
The only NSF standard written specifically for shower filters. It certifies free-chlorine reduction at the point of use. Read our plain-language breakdown.
Trust, verified
Standards & Certifications
Shower-filter marketing is full of unverified "certified" claims. We link our certifications to the public databases that actually verify them, and explain in plain language what each standard tests.
Verify on the NSF database
Every certification claim should be checkable. Search the public NSF listing to confirm a product's certificate number and scope.
Additional standards — in progress
We are completing documentation for NSF/ANSI 42 (aesthetic effects), NSF/ANSI 53 (health effects such as PFAS) and material-safety certification covering the housing, hose and cartridge media. Certificate numbers and scope will be posted here once verified.
ZOOSHEN will never display a certification badge we cannot verify in a public database. If you need a specific certificate for procurement, contact our team.