Consumer Resources

As an independent global health and safety organization, NSF International tests and certifies products and writes standards for the food, water and consumer goods industries. Founded in 1944 as the National Sanitation Foundation, we changed our name to NSF International in 1990 as we expanded our services worldwide. The letters NSF do not represent any specific words today.

Frequently Asked Questions about Supplements

If you’ve shopped for supplements recently, you’ve probably noticed that the shelves are filled with many different types of products. While the array of choices may seem overwhelming at first, product labels can help guide your decision. Read our answers to frequently asked questions about supplements and vitamins to help.

Read More

Latest News

See all related news

Most Popular Q&A

  • Open What does NSF certification of bottled water cover?

    NSF certification involves annual, unannounced inspections of a company’s bottling facility covering every aspect of the bottling process from source to packaging. Production facilities are audited for good manufacturing practices as well as risk management systems to help ensure that the final product is safe. As part of the certification process, we extensively test product samples for over 160 impurities to confirm they meet applicable federal and/or state standards. NSF certification also helps ensure that products are labeled with the proper standard of identity for the type of water indicated on the label and that any added ingredients are properly disclosed.

    Look for the NSF mark on the product label or check the NSF online listings to see if your favorite bottled water brand is NSF certified.

  • Open Which kitchen appliances did NSF find to harbor the most germs?

    Because of NSF’s role in evaluating the cleanability of common kitchen tools and appliances used in the home, in 2013 our microbiologists analyzed 14 common kitchen items in several homes for the presence of four different types of microorganisms:  E. coli, Salmonella, yeast and mold, and Listeria.

    Our study found that many common kitchen appliances used to prepare food contained one or more of the organisms listed above, with refrigerator vegetable and meat compartments as well as blender gaskets being the germiest.

    Read more about this study, including what other kitchen items were found to contain potentially harmful microorganisms as well as recommended cleaning instructions for each item.

  • Open Is PEX pipe safe for potable water?

    PEX tubing that is certified to NSF/ANSI 61 is considered to be suitable for drinking water applications. Certification for potable water contact will typically be noted on the product by an NSF-61 or NSF-pw designation (for smaller fittings, the certification mark may be on the packaging only).

    Not all PEX pipe is intended for potable water contact. For example, pipes with only an NSF-rfh certification are intended for radiant floor heating applications and should not be used for drinking water contact.

  • Open What does it mean when a supplement is NSF Certified for Sport®?

    Products that are specifically targeted for use by athletes can be evaluated under the NSF Certified for Sport® program. In addition to meeting all requirements for good manufacturing practices (GMPs) and NSF/ANSI 173:  Dietary Supplements for content and labeling, products are also analyzed to confirm they do not contain substances banned by most major athletic organizations. Ongoing monitoring helps ensure products continue to comply with all requirements to maintain product certification.

    Visit the NSF Certified for Sport® website  for a full list of NSF certified sport supplements.

  • Open Where can I buy a replacement filter for my water system?

    As an independent certification organization, NSF would not be involved in the manufacture or sale of any of the products that we certify nor their replacement components. Please contact the manufacturer of your water treatment system directly to find out where replacement filters are sold for your specific unit.

    To ensure ongoing performance, it is important to always use the correct manufacturer’s replacement cartridge identified in the owner’s manual. Failure to do so could result in the system leaking or not reducing contaminants effectively.

  • Open How long can foods be safely left out of the refrigerator?

    Perishable cooked foods should be placed in the refrigerator or freezer within two hours of being cooked, or one hour on very hot days (those over 90° F). To help speed cooling, divide larger quantities of food into several smaller, shallow containers.

  • Open What do the letters NSF stand for?

    The letters in our organization’s name do not represent any specific words today. NSF International was founded in 1944 as the National Sanitation Foundation. The name of our organization was changed to NSF International in 1990 when the National Sanitation Foundation and NSF Testing Labs merged. A brief history of the NSF organization is available on our website.

  • Open Are organic products completely free of pesticide residues?

    Although certified organic products must be grown, processed and handled without the use of pesticides or most other synthetic chemicals, it is possible for organic crops to be inadvertently exposed to agricultural chemicals. To help limit the impact of non-organic agricultural practices, National Organic Program (NOP) standards set strict requirements for organic producers and handlers, including requiring buffer zones between conventional and organic growing fields as well as storage of organic products above or separate from conventional products to avoid cross-contamination.

  • Open Are there any alternatives to using chlorine to disinfect pool water?

    There are several types of pool disinfection systems that have been certified for compliance with NSF/ANSI 50: Pool Equipment, including copper or copper/silver ionization systems, ozone generators and ultraviolet disinfection systems. It is important to note that most system manufacturers still recommend that pool owners use a small amount of chlorine or bromine to help oxidize organic matter such as skin cells, oil and hair (this is mandatory for commercial pools).

  • Open What is NSF/ANSI 40?

    NSF/ANSI 40: Residential Wastewater Treatment Systems is an American National Standard that helps verify whether packaged residential wastewater treatment systems are able to effectively treat wastewater generated from an individual residence. These systems are like a miniature municipal treatment plant and are intended for use in areas where traditional septic systems cannot be used. The unique design and components of these systems accelerate the wastewater treatment process, and because the effluent produced is significantly superior to that of a traditional septic tank, there is typically greater flexibility when disposing of the treated effluent.

See all related Q&A

Latest Tweets

Like Us on Facebook

Consumer Resources Mailing List

Receive NSF consumer updates.

View Mailing List Archives