22 3200 - Domestic Water Treatment Equipment
22 3100 - Domestic Water Softening
22 3240 - High Purity Water Systems
- American Ultraviolet Company
- Amiad Filtration Systems
- A.J. Antunes & Co.
- Aquathin Corporation - Established 1980. Manufacturers water purification systems for residential, commercial, laboratory markets, both domestic and international.
- Atlantic Ultraviolet Corporation
- AXEON Water Technologies - specializes in reverse osmosis, membranes, filters, nano filtration, ultra filtration, and components.
- Calgon Carbon Corp.
- ClearWater Enviro Technologies
- Culligan International Company
- EcoWater Systems - NorthStar
- Environmental Water Systems
- Flint & Walling
- Griswold Water Systems
- Marlo Incorporated
- Moen - Puretouch
- Nimbus Water Systems
- Pure Aqua - Reverse osmosis systems, automatic media filters, cartridge filters, water softeners.
- Superior Water Conditioner
- Triangular Wave Technologies
- UV Resources (UVR)
- Waterboss - Water softeners, water filtration systems, water filters and reverse osmosis water filters.
- Whirlpool Corporation