Water Filter Knowledge

Water Filter Standards

What should I look for when choosing a Water Filter?

Look for the NSF Standard Rating

NSF is an independent global health and safety organization.

What does NSF do?

Founded in 1944 as the National Sanitation Foundation, NSF International tests and certifies products and writes standards for the food, water and consumer goods industries. The name was changed to NSF International in 1990 as services were expanded worldwide.

1. NSF International is a global, independent, public health and safety organization with a mission to protect and improve human health.
2. Dedicated staff in North America, Europe and Asia to assist in product certification.
3. Over 200,000 square feet of laboratory space with one of the largest drinking water treatment unit test facilities with the ability to perform full chemical, microbiological and physical testing.

NSF/ANSI 42: Aesthetic Effects 

• NSF/ANSI 42
  Filters are certified to reduce aesthetic impurities such as chlorine and taste/odor. These can be point-of-use (under the sink, water pitcher, etc.) or point-of-entry (whole house) treatment systems.

NSF/ANSI 42 is one of two main NSF standards for evaluating safety and integrity of residential water filters. NSF/ANSI 42 establishes the minimum requirements for the certification of POU/POE filtration systems designed to reduce specific aesthetic or non-health-related contaminants (chlorine, taste, odor and particulates) that
may be present in public or private drinking water.
The scope of this standard includes material safety, structural integrity and aesthetic, structural integrity and aesthetic claims. The most common reduction claims addressed by this standard are chlorine, chloramines, iron, manganese, hydrogen sulfide, pH neutralization and zinc reduction. In addition, products certified only as components are found under NSF/ANSI 42 and are evaluated for material safety and, if pressure bearing, structural integrity.

NSF/ANSI 53: Health Effects

NSF/ANSI 53

• Filters are certified to reduce a contaminant with a health effect. Health effects are set in this standard as regulated by the U.S. Environmental Protection Agency (EPA) and Health Canada. Both standards 42 and 53 cover adsorption/filtration which is a process that occurs when liquid, gas or dissolved/suspended matter adheres to the surface of, or in the pores of, an adsorbent media. Carbon filters are an example of this type of product.

NSF/ANSI 53 is the second NSF benchmark standard which addresses reduction claims for residential water filters. Standard 53 establishes the minimum requirements for the certification of POU/POE filtration systems designed to reduce specific health-related contaminants, such as Cryptosporidium, lead, volatile organic chemicals (VOCs) and asbestos that may be present in public or private drinking water.
The scope of this standard also includes material safety, structural integrity and other health-related contaminant reduction performance claims. The most common reduction claims verified by this standard are heavy metals, inorganics and volatile organic chemicals.