Ultraviolet (UV) technology has been used for more than seven decades to eliminate disease-causing microorganisms, primarily in industrial and commercial applications. Today; however, this technology is gaining popularity in the residential sector because it can be applied to almost any water system, It adds no chemicals to the water,  It wastes no water and it's inexpensive to maintain.

To produce UV energy, electrical current stimulates mercury vapor held between the electrodes of a fluorescent-like lamp. The most commonly used UV lamp is a low pressure mercury vapor lamp with an energy output close to 265 nm most effective at killing microbes. Germicidal UV lamps are made with "hard glass" quartz which transmits 92 percent of UV energy far more than alternative materials.

Waterborne diseases may be caused by a wide variety of pathogenic microorganisms. Most are made up of a cell wall, a cytoplasm membrane and a DNA-bearing nucleic acid. Microbes are destroyed when UV light penetrates the cell wall and cytoplasm membrane and is absorbed by the nucleic acids. The UV energy rearranges DNA molecules and prevent the cells from reproducing. It's then considered dead for all practical purposes. The degree of destruction of microbes is a product of UV intensity multiplied by contact time.

Ultraviolet is a safe, clean, easy-to- maintain method of assuring that water is free of bacteria. It is a proven technology that has no significant drawbacks. In some applications, its initial cost is a bit more than chlorination, but because of its low operating cost, it quickly pays for itself. It is essentially trouble-free. Most systems require only an annual change of lamp?like changing a light bulb?and a change of filter cartridges if the unit has accompanying filters.

The whole house Pura UV systems are design to convert common tap water into disinfected and pure water. The Ultraviolet Filtration System filters water at a flow rate of 8-10 gallons per minutes. Water is channel through a Stainless Steel UV Reaction Chamber. This point of entry (POE) Ultraviolet Filtration is usually installed in the main water feed of the house and its advance technology ensures the removal of microbiological contaminants. It's a perfect companion for a Water softener system.

Pura systems come in various sizes, from small one gallon-per-minute undersink units for drinking water to the 15-gallon-per minute ?Big Boy? series. Most of Pura sales are in the eight-to-ten gallon-per-minute ?UV 20? whole house series.