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NSF/ANSI 44 Technical Requirements

March 8, 2025

NSF/ANSI 44 establishes the minimum requirements for certifying residential water softeners that use a cation exchange resin regenerated with sodium or potassium chloride, which reduces hardness in public or private water supplies.

NSF/ANSI 44 establishes the minimum requirements for certifying residential water softeners that use a cation exchange resin regenerated with sodium or potassium chloride, which reduces hardness in public or private water supplies.

Depending on the regenerant, these minerals are replaced with sodium or potassium ions. Cation exchange resins regenerated with sodium chloride or potassium chloride salt are covered by NSF/ANSI 44.

By certifying to this standard, your customers can know that your product performs as claimed.

The scope of NSF/ANSI 44 includes:

  • Reduction of hardness and specific contaminants from a known quality source
  • Material safety
  • Structural integrity
  • Pressure drop
  • Softening capacity and rinse effectiveness
  • Accuracy of the brine system
  • Accuracy of information provided to end users.

For more information, download the PDF: Technical Requirements of NSF/ANSI 44

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