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NSF/ANSI 44-2024
Residential Cation Exchange Water Softeners
The manual, auto-initiated, and demand-initiated regeneration (DIR) residential cation exchange water softeners addressed by this standard are designed for the reduction of specific substances that may be present in drinking water (public or private) considered to be microbiologically safe and of known quality. Systems covered under this standard are intended to reduce hardness affecting the aesthetic quality of water.
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