Contaminant Reduction Claims
At NSF, we certify various water treatment systems, from filtration to reverse osmosis, which are designed to reduce contaminants. We have listed certified products based on the pollutants we regularly ask about to help you find the best water filter for your home or office. Remember that no systems may be certified to reduce that specific contaminant if a filter type is not listed. Contact us with your questions.
Lead
View all filters and systems certified by NSF to reduce lead.
- Water Pitchers With Filters
- Faucet Filters
- Under-Sink Filters
- Reverse Osmosis Filters
- Counter-Top (Manual-Fill) Filters
- Counter-Top Filters Connected to a Sink Faucet
- Refrigerator Filters
- Aftermarket Refrigerator Filters
- Integrated Refrigerator Filters
Arsenic (Pentavalent) for Treating Incoming Levels of <=50 ppb
View all filters and systems certified by NSF to reduce arsenic less than 50 ppb.
Bacteria/Coliform/Cyst/Virus
Chlorine
View all filters and systems certified by NSF to reduce chlorine.
- Whole House Systems
- Faucet Filters
- Water Pitchers With Filters
- Counter-Top Filters Connected to a Sink Faucet
- Counter-Top (Manual Fill) Filters
- Under-Sink Filters
- Reverse Osmosis Systems
- Refrigerator Filters
- Integrated Refrigerator Filters
- Aftermarket Refrigerator Filters
Chloramine
View all filters and systems certified by NSF to reduce chloramine.
- Faucet Filters
- Counter-Top Filters Connected to a Sink Faucet
- Counter-Top (Manual-Fill) Filters
- Under-Sink Filters
- Reverse Osmosis Systems
Chromium (Hexavalent)
View all filters and systems certified by NSF to reduce hexavalent chromium.
Fluoride
Nitrate/Nitrite
PFOA/PFOS
View all filters and systems certified by NSF to reduce PFOA/PFOS.
- Counter-Top Filters Connected to a Sink Faucet
- Under-Sink Filters
- Reverse Osmosis Systems
- Refrigerator Filters
- Aftermarket Refrigerator Filters
- Refrigerator Filters (Integrated)
- Water Pitchers With Filters
- Whole-House Filters
Total Trihalomethanes (TTHM) and Volatile Organic Compounds (VOCs)
View all filters and systems certified by NSF to reduce VOCs including TTHM.
How NSF Can Help You
What’s New with NSF
Information Systems Security Association (ISSA) Welcomes NSF’s Brian Schultz into the 2026 Hall of Fame
September 10, 2026Lifetime achievement recognition honors exceptional leadership and lasting contributions to the cybersecurity profession.NSF Welcomes Nicole Parent Haughey to Board of Directors
September 10, 2026NSF's appointment of Nicole supports the organization's continued focus on long-term growth and transformation.
NSF Launches Independent Certification Standard for Compact Products
August 25, 2026New third-party certification verifies products cutting materials and shipping impacts while maintaining safety and performance.
CELSIUS® Products Earn NSF Certified for Sport® Certification
August 20, 2026CELSIUS® has earned NSF Certified for Sport® certification for select products, including the CELSIUS VIBES line, reinforcing the brand’s commitment to quality, transparency and consumer trust.