Clarifying Terms

• Calling sodium hypochlorite "liquid chlorine" is technically a misnomer. True chlorine (Cl2) is a gas. It kills germs, but it is heavy and impractical. Most pool owners use "chlorine" in a more convenient form, such as calcium hypochlorite (CaOCl2) or lithium hypochlorite (LiOCl). For convenience sake, the pool industry refers to all chlorine-based pool sanitizers as "chlorine."
  
  

Concentration

• The most important difference between bleach and liquid chlorine is their concentration. According to the United States Environmental Protection Agency, bleach is a 5.25 percent sodium hypochlortite solution. That means that approximately 94.75 percent of that bottle you bought from the supermarket is some other chemical, probably just water. Liquid chlorine, on the other hand, is somewhere between 10 percent and 15 percent, according to Purdue University, making it at least twice as potent as bleach.
  
  

Similarities

• Ultimately, bleach and liquid chlorine have the same job. They kill harmful bacteria and dangerous microbes that can affect the health of people who are exposed to them. They also "burn off" unwanted impurities through a process called "oxidation." In other words, we use the same tool to keep our clothes and our swimming water healthy.
  
  

Pool Chlorine as Bleach?

• Be careful with your laundry.laundry image by timur1970 from Fotolia.com
  
  The danger of using pool chlorine with laundry is obvious to anyone to anyone who has ever added too much bleach to a washing machine. Because it is so much more concentrated, the chlorine will whiten the color of clothing and burn holes through the fabric. Even if you carefully measure a small amount, a miniscule misjudgment will ruin your laundry.
  
  

Bleach as Pool Chlorine?

• You could use bleach to sanitize pool water, but there is no economic benefit.swimming-pool image by Aleksandr Ugorenkov from Fotolia.com
  
  It is theoretically possible to sanitize a pool with bleach, but not economical. Because it is so much weaker, bleach would have to be added at twice or three times the regular dosage of liquid chlorine to achieve a comparable result. The checkout people in your supermarket will start calling you the "Bleach Man/Lady" behind your back. Also, some bleaches, like "scented" brands, contain other chemicals that will linger in the pool and cause problems with chemistry and filtration.