Water purification equipment can conveniently be separated into products intended for Whole House Water and Drinking Water. This distinction is based on the level of water purification required for different water uses.

Drinking Water (Point of Use) is water used primarily for drinking, preparing beverages and cooking. This is the water that has the greatest impact on health and wellness and therefore must be of high purity.

Whole House (Point of Entry) is for general household use including kitchen, laundry, bath, water appliances and landscape. This water is generally treated by whole-house systems and may include the removal of one or more contaminants such as sediment, hardness, iron, manganese, nitrate, radionuclides, arsenic, hydrogen sulfide, tannins and other elements.

Some contaminants may be classified in multiple categories, according to their concentration and the preferences of the consumer. For example, a high level of radionuclides may be unacceptable for some consumers and they opt for Point of Entry (anion exchange, turnkey, or whole-house removal) treatment for all Whole House Water; but other consumers with high levels of radionuclides want the radionuclides removed only from their Drinking Water by Point of Use Reverse Osmosis (RO).