Many cities purify their municipal water supply with
chlorine (= chemical element Cl). You can do the same in a survival scenario using household bleach. Most homes, businesses, and
retail establishments(=shops, stores) keep a bottle of bleach on hand, and memorizing the purification dosages could keep you from a
gastrointestinal nightmare(=bugs, pests and other troubles with your guts). Household bleach is sold as a 6–8% concentration of active
sodium hypochlorite (NaClO). This is often marketed as Extra Concentrated. The Environmental Protection Agency (EPA) recommends using 2 drops of this concentration per 1 quart or liter of water. Make sure the water is clear to begin with and that you wait a full 30 minutes after adding the bleach before using it. Cloudy or murky water drastically affects the effectiveness of almost all chemical purifiers. Also, only use regular
unscented (=having no smell) bleach.
