Reverse osmosis (RO) drinking water systems provide the highest level of clean, potable (safe to drink) water. RO systems press water through a semipermeable membrane using pressure, combined with a number of other filtration steps. A reverse osmosis drinking water system has the following:
- Prefilter – captures larger particles, chlorine, other substances, and protects the semipermeable membrane.
- Semipermeable membrane – captures more contaminants, including but not limited to Arsenic, Barium, Cadmium, Chromium (Hex), Chromium (Tri), Copper, Cyst, Fluoride, Lead, Radium, Selenium, Select Volatile Organic Compounds (VOCs), Total Dissolved Solids (TDS), and Chlorine Taste and Odor.
- Activated carbon filter – removes residual taste, odor, and some organic contaminants.
- Storage tank – a NSF certified tank which holds the clean water for use.
While reverse osmosis technology can be used as a whole-home (Point-of-Entry) water filtration system, RO systems are most commonly used at the Point-of-Use to condition water for drinking and cooking. Because the reverse osmosis process entails such a high degree of water filtration which is more time consuming per the amount of potable water produced, RO systems are typically installed for use in the areas of the home where water is most commonly ingested, such as kitchens and bathrooms, and RO drinking water systems require a separate dedicated faucet. Depending on the water issues which need to be addressed, there are many types of drinking water filtration systems, including those which utilize existing tap water faucets.