When comparing water treatment technologies and products, Rule #1 is to make sure the product is NSF-certified. It is not enough to simply acknowledge the NSF certification; to ensure you are getting the best system, you need to go a step further. Why is this important? Because NSF certification provides an unbiased, independent, third-party guarantee that something performs according to its claims. Consumers can be confident that a product works as stated when it is certified by NSF International, the premier independent certification organization for drinking water treatment in the world. Certification allows for an “apples-to-apples” comparison with other drinking water systems, because all NSF-certified systems have undergone the same rigorous and comprehensive testing.

Fortunately, making sure a product is NSF-certified is easy: simply check to see if they have the NSF certification seal on the product packaging, and then go to the NSF website (www.nsf.org) to double-check that the specific product by that manufacturer is currently certified.

With all that in mind, Rule #2 is to look up the specific NSF certifications for that product, because certifications vary. For example, NSF Standard 42 (Aesthetic Effects) covers contaminants that affect the taste and odor of water, such as chlorine and particulates; NSF Standard 53 (Health Effects) covers contaminants that can cause physical harm upon exposure or ingestion, such as lead or asbestos. Different products may have different specific certified contaminants under the same certification; for example, NSF Standard 53 covers dozens of different contaminants, and one product may only be certified for one of them (e.g., lead), while another may be certified for many of them (e.g., lead, arsenic, VOCs, and PFOA). Details matter when it comes to NSF certification.

Now, let us look at phrases all-too-often used by companies to falsely bolster product performance claims: “certified to NSF standards” or “tested according to NSF standards.” At a glance, this may appear to be the same thing as NSF-certified; after all, the product is certified to the same standards, right? Remember, though, that details matter when it comes to NSF certification. A company’s internal laboratory will not be unbiased and independent. Other independent laboratories will not follow the same stringent, multiphase testing and certification protocols performed by NSF International.

Think about all the unanswered questions with the phrase, “certified to NSF standards”: Who performed the product testing? Was the laboratory certified? Were the tests performed in-house by the company? Who certified the test results? What were the testing processes? Were the tests performed on a brand new filter and at the filter’s end-of-life? Was the quality of the parts and housing tested? What amount of contaminant was added to the water? How often were the tests performed? How many gallons of water were tested?

“Certified to NSF standards” or “tested according to NSF standards” does not rule out internal, manufacturer-controlled testing, whose results cannot be guaranteed to be impartial and unbiased. Nor does it ensure that the product performance was actually tested for the entire life of the filter – some companies only test the water for a few gallons, and base their performance claims off of that limited data.

True NSF testing and certification involves multiple stages and criteria; for drinking water treatment systems, the main testing criteria are designed to verify that:

  • The contaminant reduction claims are true from the first to the last drop of water.
  • The housing, parts, and filter do not leach anything harmful into the water.
  • The system is structurally sound.
  • The product labeling, advertising, and literature are accurate and are not misleading.
  • The materials and production process have not changed, allowing for consistent product quality over time.

NSF certification testing does not just check the product submitted to them for testing. NSF goes further by conducting unannounced manufacturing inspections: NSF inspectors enter the manufacturing plant and take product and literature off of the manufacturing and assembly lines to ensure that the item submitted for testing is the same as the product being sold. In addition, NSF also purchases product for sale – either in a storefront or online, again to ensure that the product sold and the included literature are in compliance and match the products and literature submitted for testing and produced at the manufacturing plant.

When a company or product uses the phrases “certified to NSF standards” or “tested according to NSF standards,” they are attempting to use the power and integrity of true NSF certification to bolster the reputation of their products without having to go through the rigorous certification process. It is a shortcut that uses wordplay to convince consumers that an unproven product is just as good as tested and certified products.

One example: “Company X” has drinking water treatment products that claim “certified water filtration” that have been “tested by independent laboratories” to ANSI/NSF standards; but, none of the products are NSF-certified. Some of their products feature certification by IAPMO (International Association of Plumbing and Mechanical Officials), but of those products, almost all of them possess IAPMO certifications that have been expired for several years. In fact, only one of their products holds a current certification by IAPMO, and only for one specific contaminant. As you can see, between the partial facts (certified, but not by NSF International), implied facts (independently tested to NSF standards, but not NSF-certified), and outdated facts (products that were certified years ago, but whose certification is currently expired), many company product claims can mislead unsuspecting consumers.

Another example occurs when a company or product claims “tested to NSF standards,” but fails to specify that they only tested the product for limited quantities of water (e.g., testing only 10 gallons of water versus testing the publicized life capacity of the filter) and/or at unrealistic usage parameters (e.g., at a low flow rate, or at below average water pressures – either of which would allow for enhanced performance data for the tested filter).

Yet another certification claim shortcut is for companies to have only one product NSF-certified, yet imply through advertisement or packaging text that all of their products are NSF-certified.

In contrast to these less-than-forthright practices, as part of Multipure’s NSF-certification process, NSF International tested Multipure drinking water systems for DOUBLE the claimed capacity of the entire life of the filter. So the Aquaversa, rated for a 750 gallon capacity, has been NSF-tested-and-certified for all of its contaminant reduction claims for 1500 gallons.

In the end, it is always up to the consumer to properly research the validity of any product’s performance claims. The NSF certification seal is a good first indicator as to a product’s quality, but an informed and savvy consumer will dig deeper to check the details of the product performance and certifications. In this way, anyone can determine if a drinking water system is really as good as its claims, or if its performance claims do not hold water (pun intended).

For more information about NSF certification, please visit https://www.multipure.com/purely-social/science/nsf-water-filtration-certifications/.

To view Multipure’s product performance data and certification listings, please visit https://www.multipure.com/nsf-certification.html.