It’s hot out and there’s no school, so most days between the months of June and September, we’re spending a lot of quality time in a swimming pool—which we know is loaded with pool chlorine. So what exactly is chlorine? According to the Centers for Disease Control and Prevention (CDC), “chlorine is used in drinking water and swimming pool water to kill harmful bacteria. It is also as used as part of the sanitation process for industrial waste and sewage.” So far so good…chlorine is used to kill bacteria. We like the sounds of that. Here are some more interesting facts about chlorine.