What is NSF/ANSI 177?

By ZOOSHEN Editorial Team · 9 月 19, 2026 · Updated 9 月 19, 2026 1 min read

NSF/ANSI 177 is the on…

NSF/ANSI 177 is the only certification standard specifically for shower filtration. It tests the reduction of free chlorine in shower water. Other common standards — NSF 42 (taste/odor) and NSF 53 (health effects) — apply to drinking water systems, not shower filters. Always check which standard a filter actually carries.

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