Understanding Particle Sizes (See Chart Below)
Reverse Osmosis filters are designed with pores that are only large enough to allow water molecules thru them, thereby effectively filtering out contaminants.
In understanding water molecule size, its important to know that the shape and size of a water molecule is not a perfect sphere. The oxygen atom is flanked on either side by two hydrogen atoms at an angle of about 104.45 degrees. The distance from the center of the oxygen atom to the center of one of the hydrogen atoms is about 95.84 pm (picometers – trillionths of a meter), which equals 0.0000958 µm (micrometers, or microns).
A perfect sphere that would tightly encompass a single water molecule is closely calculated to be about 0.000282 µm (micrometers – millionths of a meter) in diameter. You can say this number as "Two-Hundred Eighty-Two picometers" or (282 trillionths of a meter). Now that’s small!
Note: See chart below where the water molecule (H2O) is located. The molecules CL2 is chlorine, and C6H6 is benzene. As you can see, these molecules are slightly larger than a water molecule, and slightly larger than the largest pores in the RO membrane, about 0.0005 µm ("half a nanometer", or "500 picometers").
These impurities will not physically fit through the pores of a Reverse Osmosis filter, and will be separated from your drinking water.
0.000282 µm (micrometers – millionths of a meter) equals,
0.282 nm (nanometers – billionths of a meter) equals,
282.0 pm (picometers – trillionths of a meter).
Click Chart to Enlarge
The human eye is capable of seeing particles down to about 40 microns without the use of a microscope. Use this micron particle size chart to give you perspective on particle sizes.