How it works
Household systems usually include sediment and carbon filters plus the membrane. Some water becomes treated product water, while a separate stream carries concentrated material to the drain.
What people often miss
Removal rates vary by contaminant and system. Reverse osmosis can also remove useful minerals, waste water, and require maintenance to prevent poor performance.
Why this question comes up
The process is more selective than a basic carbon refrigerator filter but is not maintenance-free.
Key points
- Reverse osmosis uses pressure to push water through a membrane that allows water molecules through while rejecting many dissolved substances.
- Household systems usually include sediment and carbon filters plus the membrane. Some water becomes treated product water, while a separate stream carries concentrated material to the drain.
- Removal rates vary by contaminant and system. Reverse osmosis can also remove useful minerals, waste water, and require maintenance to prevent poor performance.
Bottom line
Reverse osmosis uses pressure to push water through a membrane that allows water molecules through while rejecting many dissolved substances.
Source and verification
This Answer was checked against U.S. Environmental Protection Agency. Follow the source for the full official explanation and any later updates.