Following are website links to helpful information regarding water purification methods, standards, and technologies.

  • CDC Home Water Filters Selection – Centers for Disease Control and Prevention guidelines for choosing home water filters and other water treatment systems. Explains NSF International ratings, water filter “pore size”, water-related emergencies and outbreaks, well testing and much more.
  • EPA Home Drinking Water Filter – United States Environmental Protection Agency Ground Water and Drinking Water fact sheets and other resources. Topics include facts about home water filtration systems, bottled water fact sheet, private drinking water wells, regulatory requirements for public water systems, consumer confidence reports and much more.
  • EPA Water Filtration Facts – United States Environment Protection Agency Water Health Series document on Filtration Facts.
  • NSF Drinking Water Publications – NSF consumer resources and drinking water publication: Consumer Guide to Fluoridation Products and Fluoride.
  • NSF Water Treatment Standards – Explanation of NSF standards for water treatment systems. Includes
    • NSF/ANSI 42 – Filters such as point-of-use (countertop, under sink, water pitcher, etc.) and point-of-entry (whole house) that are certified to reduce aesthetic impurities including chlorine and taste/odor.
    • NSF/ANSI 53 – Filters such as carbon filters certified to reduce a contaminant with a health effect including adsorption/filtration and dissolved/suspended matter.
    • NSF/ANSI 44 – Water softener standards.
    • NSF/ANSI 55 – Ultraviolet treatment systems used to inactivate or kill bacteria, viruses and cysts in drinking water.
    • NSF/ANSI 58 – Regulations for Reverse Osmosis Systems.
    • NSF/ANSI 62 – Safety of distillation systems regarding contaminants that convert readily into gases and carry over with the water vapor.
    • NSF/ANSI 177 – Shower filters for homeowner’s shower head.
    • NSF/ANSI 244 – Microbiologic safety of public water supply filters.
    • NSF/ANSI 401 – Treatment systems for emerging contaminants for point-of-use and point-of-entry systems.
    • NSF P231 – Microbiological water purifiers.
  • Water Purification Wiki – Overview of water purification purposes and processes. Includes water sources; water treatment; pH adjustment; coagulation and flocculation; sedimentation; sludge storage and removal; floc blanket clarifiers; dissolved air flotation; filtration types; removal of ions and other dissolved substances; and disinfection with Chlorine, Chlorine Dioxide, Chloramination, Ozone disinfection, Ultravioliet Light (UV), ionizing radiation, Bromination and iodination.
  • Water Quality Association (WQA) – Third-party product certification, membership, professional certification, education events, learn about contaminants, find WQA certified products.