Investing in a water purification system for your home can ensure your family receives the cleanest, safest drinking water possible. There are many different types of purification system on the market, however, and some of them offer significant advantages over other models. Choosing the best system depends on your family's individual needs as well as what types of contaminants are your greatest concern. The best water purifiers use a mix of technologies to provide maximum safety.
Physical filtration is one way to purify water, although only the most advanced filters will catch most types of contaminant. Filters with a pore size smaller than one micron are effective against many different types of particles as well as parasites such as giardia and cryptosporidium. These filters bear the NSF Standards 53 or 58, according to the Centers for Disease Control and Prevention. Ceramic water filters are available with a pore size as small as .22 micron, and these will trap and filter out bacterial contaminants. Viruses are much harder to filter out, as they can be as small as one-tenth of a micron, requiring a disinfection system to remove. Most water filters incorporate activated charcoal, a substance which is excellent at filtering out organic compounds, toxic substances, and chemical contaminants.
When it comes to biological contaminants, one effective method of neutralizing them is through an ultraviolet disinfection system. These units pass water through a glass tube, exposing it to a heavy dose of ultraviolet radiation. This sterilizes any microorganism that may be present in the water. These units are excellent at neutralizing bacteria and viruses, but are ineffective at removing dissolved particles and chemical contaminants. Because of this limitation, ultraviolet disinfection units usually include a physical filter of some kind to provide complete water purification.
A reverse osmosis system uses a semi-permeable membrane to thoroughly filter water. Normally, water moves across such a membrane from an area of less contamination to more contamination in an attempt to balance the ratio of water to dissolved solids. Reverse osmosis units use water pressure to reverse this movement, trapping contaminants against the membrane and forcing pure water through to the other side. According to the Environmental Protection Agency, reverse osmosis purifiers are effective against all types of microorganisms and many types of chemical contaminant.