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Inside UL: Deciphering Consumer Water Filters


June 6, 2018

Water contamination issues continue to splash headlines across the U.S. with many considering the use of water filters to help remove contaminants. But how does one decide between filter types?

If it’s not one public water system, it is another, as shown by a 2016 study that revealed nearly 21 million Americans, or 6 percent of the U.S. population, received water from systems that violated health standards set by the U.S. Environmental Protection Agency (EPA).

Because of ongoing concerns about contaminated water, more and more consumers are using water filters to help protect themselves and their families. Transparency Market Research (TMR) predicts the water purification market will grow at a CAGR (compound annual growth rate) of 8.4 percent over the next seven years to an estimated valuation of USD 110 billion by 2025.

Water filters can help address many health and non-health related contaminants to keep water safer and great tasting. There are hundreds of brands available in today’s marketplace, offering several styles to accommodate a consumer’s needs. Pitchers, dispensers, faucet-mounted, under-the-countertop, on-the-countertop, refrigerator and whole house filters make up a significant portion of available options.

But with so many options how do consumers decide which brand is worth the money?

According to Amanda Fisher, business development manager for UL’s water systems program, the first step is to determine the state of water currently flowing out one’s taps. The EPA offers a plethora of information on its drinking water and groundwater webpage. You can review your local consumer confidence report (CCR) or learn all about lead in drinking water, among other topics in articles offered throughout the site.

Finding the right filter to reduce your area’s contaminants is much easier after reviewing your local CCR. Look for a filter that claims to remove the containments identified by the CCR or those that most concern you. When selecting a filter, you may also want to choose one that has been tested and certified by a third party to applicable water industry standards.

UL offers independent testing and certification to voluntary industry standards for manufacturers of residential drinking water filters, including NSF/ANSI 42 – Aesthetic Effects and NSF/ANSI 53 – Health Effects. Both standards have identical requirements when it comes to evaluation of the material safety and structural integrity, but differ in the type of contaminant reduction testing performed.

For example, NSF/ANSI 53 evaluates filters claiming to reduce contaminants that are considered harmful by the EPA. Such contaminants include lead, arsenic, mercury, nitrates/nitrites, volatile organic compounds (VOC), microbial cysts such as Giardia and Cryptosporidium and others. A second standard, NSF/ANSI 42, determines if the filter being tested minimizes aesthetic, non-health related contaminants from public or private water supplies, such as chlorine (taste and odor), chloramine, hydrogen sulfide, phenol, iron, manganese, pH neutralization, zinc and particulate reduction.

In addition to contaminant reduction testing requirements, NSF/ANSI 42 and NSF/ANSI 53 also set criteria for literature that must accompany each system. The literature criteria are quite involved and have specific requirements for the data label, the manual and the performance data sheet. The language needs to be specific and include actual data as well as clearly state the percentage of contaminant reduced by the product.

“The literature review is designed to help protect the consumer,” Fisher said. “It is to make sure the consumer understands what the product does and does not do.”

Water filtration devices that have been certified to NSF/ANSI 42 and NSF/ANSI 53 standards by an ANSI accredited third-party certification organization, such as UL, have undergone a rigorous evaluation and testing process. Consumers choosing these filters can rest assured that the products perform as expected.

A portion of this article is an excerpt from A Path to Success: Certification of Drinking Water Filtration Devices.