With more and more Indians becoming aware of the hazards of drinking impure water, the demand for effective water purifiers is growing rapidly. The majority of intestinal disorders and infections are caused by water borne micro organisms. As a result, the number of consumers looking for reliable purification options is increasing not only in the metros but also in towns across India.
Tap water may contain both biological and chemical contaminants. Biologically contaminated water contains microbes such as viruses, which may result in minor to serious infections, and bacteria and giardia that lead to stomach disorders. Common causes of chemical contamination are improper treatment of industrial waste and pesticide overspill. If chemically contaminated water is used regularly it could lead to serious long term ailments.
Boiling is one of the oldest methods of purifying water and is said to kill most micro organisms. Candle water filters are still used in many households across India. However, the pace of life in urban India has quickened so incredibly over the last decade or so that few householders now have the time to treat water manually. Also, mechanized water purification systems are often considered more reliable as far as eliminating micro organisms is concerned.
How does one choose from the plethora of technologies and brands now available in India? Which water purification system would be best for you? The two parameters of selection here would be degree of purification and price. Different technologies deliver differing degrees of purity. Water may be purified using the following technologies:

Domestic water purifiers usually use chemical purification, ultraviolet treatment and filtration, or reverse osmosis. Major vendors include Eureka Forbes, Philips, Hindustan Unilever, Whirlpool and Kent. Eureka Forbes is the overall market leader. Others are Ion Exchange, Zeolite, Kenstar and Maharaja Whiteline. Prices range from less than Rs.2000 to Rs. 25000.