Calcium hypochlorite, Ca(OCl)2 is also known as Dry Chlorine or HTH, Calcium hypochlorite is used to disinfect drinking water. Generally, the commercial substance is sold with a purity of a 68% (with other additives and contaminants varying based upon the product's intended purpose).Chlorine has a variety of uses. It is used to disinfect water and is part of the sanitation process for sewage and industrial waste. During the production of paper and cloth, chlorine is used as a bleaching agent. It is also used in cleaning products, including household bleach which is chlorine dissolved in water.