When a water filtration company claims their system removes contaminants, that claim means nothing without independent verification.
NSF International is the organization that provides that verification. They test filtration products against established safety and performance standards, confirm the results, and certify only what the data supports. A system that carries NSF certification has been tested by a third-party laboratory — not self-reported by the manufacturer.
Every system Rein Water USA carries is NSF certified.
What the certifications actually cover
Not all NSF certifications are the same. Each standard applies to a specific set of contaminants and performance criteria. Here is what the relevant standards mean in practice:
NSF/ANSI 42 Covers aesthetic contaminants — chlorine taste, odor, and particulates. The minimum standard for any drinking water filter. A Brita pitcher holds this certification.
NSF/ANSI 53 Covers health-related contaminants — lead, cysts, VOCs, and certain heavy metals. A meaningfully higher bar than NSF 42, and the minimum standard for any filter making a health claim.
NSF/ANSI 58 The certification specific to reverse osmosis systems. Covers the complete system — pre-filters, membrane, post-filter, and storage tank. Verified reduction claims include TDS, fluoride, arsenic, nitrates, PFAS, chromium-6, and lead among others. This is the certification that matters most for the systems we carry.
NSF/ANSI 55 Covers ultraviolet disinfection systems. Class A certification confirms the system is capable of treating microbiologically unsafe water — bacteria, viruses, Cryptosporidium, and Giardia.
NSF/ANSI 61 Applies to all materials that come into contact with drinking water. Ensures that filter housings, tubing, fittings, and tanks do not introduce contaminants into the water they are treating.
NSF/ANSI 401 Covers emerging contaminants not traditionally regulated — including pharmaceuticals, hormones, and certain pesticides detected in municipal water supplies.
One distinction worth understanding
NSF certification is contaminant-specific. A system certified under NSF 58 for lead reduction is not automatically certified for arsenic or PFAS. Each reduction claim requires independent verification.
This matters because the phrase "NSF certified" is frequently used in water filtration marketing without specifying which standard or which contaminants are covered. Before purchasing any system — from any company — confirm which specific NSF standard applies and which contaminants are independently verified under that certification.
All of that documentation is available for every system we carry. We will provide it on request.