Problems with Chlorine

• Chlorine is generally considered safe for human exposure, but when chlorine reacts with organic materials like perspiration, natural body oils and urine, it creates chemical compounds called chloramines. In addition to imparting an offensive bleach-like odor to pool water, chloramines cause skin and eye irritation and even some respiratory problems. While these effects are usually minor and temporary, many pool owners have turned to alternative disinfecting technologies in their swimming pools.
  
  

UV Filters

• Ultraviolet filters are not a replacement for chlorine disinfection, but can be added to a chlorine-disinfected pool in order to remove chloramines. UV filters are commonly used to disinfect food, to purify water supplies, and are in the production of pharmaceuticals. In addition to removing chloramines, UV filters are effective at removing microorganisms that have developed a natural resistance to chlorine like cryptosporidium, a potentially dangerous intestinal worm that cannot be killed by chlorine.
  
  

Effectiveness

• The City of Portland conducted a test of the effectiveness of UV filters by installing a UN filter in Mt. Scott City Pool. Researchers found an 85 percent reduction in chloramides in the pool water, from 2 ppm to 0.3 ppm. Since chloramides can also lead to corrosion of unpainted metal surfaces around pools, UV filters also led to lowered maintenance and upkeep costs for the Scott City Pool.
  
  

Other Considerations

• There is another more commonly used method for removing chloramides from pool water, the method sometimes called "superchlorination" or "shock treatment chlorination." This method involves introducing huge amounts of chlorine into the water, introducing other chemicals into the water to diminish chlorine concentration and closing the pool until chlorine levels drop back down to safe levels. When considering whether a UV filter is a good choice for your pool you should weigh the added cost of installing a UV filter against the health benefits it can deliver by reducing the harmful side-effects of chlorination.