To understand reverse Osmosis we must first understand osmosis. During natural osmosis, water flows from a less concentrated solution through semipermeable membrane to a more concentrated saline solution until concentrations on both sides of the membrane are equal. (see figure 1)

Reverse Osmosis:

Reverse osmosis requires external pressure to reverse natural osmotic flow. As pressure is applied to the saline solution, water flows from a more concetrated saline solution through the semipermeable membrane. (see figure 2)

Reverse Osmosis Membrane:

A reverse osmosis membrane has a thin microporous surface that rejects impurities, but allows water to pass through.

The membrane rejects bacteria, pyrogens, and 85%-95% of inorganic solids. Polyvalent ions are rejected easier than monovalent ions. Organic solids with molecular weight greater than 300 are rejected by the membrane, but dissolved gases pass through.

Reverse osmosis is a percent rejection technology. The purity of the product water depends on the purity of the inlet water. The purity of reverse osmosis product water is much higher than the purity of the feed water. (see figure 3)

 

How can I find out what is in my tap water? You can contact your local health department to have your water tested for hardness, Nitrates and Total Dissolved Solids (TDS). Or, we will be happy to test your water for you....free of charge! Simply mail approximately 2ozs of your tap water to us!