NSF/ANSI 53 is the certification standard that validates health effects claims for drinking water treatment units in the United States. For PFAS-removal products, certification under this standard requires independent third-party testing demonstrating reduction of PFOA and PFOS to below 10 ng/L from an influent challenge concentration of 150 ng/L each. Achieving this certification is a prerequisite for sale of PFAS treatment products in many U.S. states and municipalities. MARISORB™, Bluelabs’ PFAS-selective adsorbent, has completed NSF/ANSI 53 certification testing conducted by KCL (Korean Conformity Laboratories), providing a robust data package that supports product deployment in regulated markets.
The NSF/ANSI 53 Certification Process for PFAS Adsorbents
Certification testing is conducted at the rated service flow and maximum rated capacity of the product configuration. For cartridge products, this means running the test unit at its specified flow rate until the rated volume of water has been processed, sampling effluent at defined intervals (typically at 10%, 25%, 50%, 75%, and 100% of rated capacity). The challenge water is prepared to a standardized composition with pH 7.5±0.5, hardness 140–170 mg/L as CaCO3, and total dissolved solids 300–500 mg/L, spiked with PFOA and PFOS at 150 ng/L each. Effluent must remain below 10 ng/L for each compound at all sampling intervals throughout the test.
Materials safety testing, conducted in parallel, evaluates extractable contaminants from all wetted materials. This component is particularly relevant for novel adsorbent materials entering the market: the media itself, along with any binder, supporting structure, or housing material, must demonstrate that it does not leach substances exceeding NSF/ANSI 61 benchmarks. MARISORB™ has completed both performance and materials safety components of NSF/ANSI 53 evaluation through KCL testing, confirming that it introduces no secondary contaminants to treated water.
What Certification Means for System Designers and OEMs
For OEMs incorporating MARISORB™ into cartridge or vessel-based products, the existence of certified performance data significantly simplifies the product certification pathway. Rather than conducting de novo performance testing on the media itself, OEMs can reference the KCL certification package as the basis for media performance claims, focusing their own testing on the specific housing geometry and flow conditions of their product configuration. This accelerates time-to-market and reduces certification cost.
For water utilities and industrial operators, NSF/ANSI 53 certification provides regulatory defensibility. Procurement specifications that require certified products protect utilities from regulatory challenge and ensure that performance claims are backed by independent data rather than manufacturer assertions alone. When evaluating PFAS-selective adsorbents, specifiers should ask for the certification certificate number, the testing laboratory, and the specific PFAS compounds covered by the certification scope—not all certificates cover the full compound list.
MARISORB™’s NSF/ANSI 53 certification through KCL represents a critical milestone for PFAS-selective adsorbent technology deployment. It demonstrates that the fluorophilic binding mechanism delivers certified, reproducible performance—not just laboratory-scale proof-of-concept results—and positions MARISORB™ as a commercially viable option for regulated PFAS treatment applications worldwide.