Household bleaches are a part of everyday life and are in nearly every American home, usually in more than one form. There are two main classes of household bleach: chlorine bleaches and non-chlorine bleaches. All of these bleaches are in a class of chemicals known as oxidative agents, meaning that they cause a chemical reaction called oxidation when they come into contact with certain stains, certain germs or other organisms, and sometimes clothing dyes.
Bleach is a very useful chemical both around the house and for large-scale use. You can use bleach to remove stains on clothing or to whiten your laundry. It's used to disinfect surfaces, too, especially in the kitchen and bathroom. You may have tried bleach to remove mold and mildew. Hospital personnel use bleach as a disinfectant, hotels use bleach to clean and disinfect bed linens and surfaces, and restaurants disinfect food preparation surfaces with chlorine bleach. People use chlorine in swimming pools to keep the water clean and raise the pH, and in much smaller concentrations to help keep municipal water supplies free of harmful organisms. Companies sometimes add chlorine bleach to industrial wastewater to reduce odor, and chlorine is used by the glass, chemical, pharmaceutical, textile, agriculture, paint and paper industries [source: Lenntech]. With its many uses, bleach its a very familiar product to most people.
While the word "bleach" entered the English language around the year 1050, bleach containing sodium hypochlorite was first manufactured in the U.S. in 1913, for use as an institutional disinfectant and a water treatment. Before that, chemicals such as borax, ammonia and lye were the most common bleaches in the U.S., and bleaches made using chlorine were generally too expensive to manufacture until the 20th century. Clorox Chemical, later called the Clorox Company, first gave samples of bleach to consumers for household use in 1922 [source: American Chemistry Council]. Since chlorine bleach was faster and more effective than the bleaches people had been using, it quickly became the most popular household bleach. Today, when we say "bleach," we usually mean chlorine bleach. So what exactly is chlorine bleach, and how does it work?