The Truth Behind That "Chlorine" Smell at the Pool

The concentration of sodium hypochlorite used for pool disinfection doesn't actually cause that smell. That odor is caused by urine from inconsiderate people. When sodium hypochlorite reacts with urea, it produces trichloramine, and that's what you're smelling. It's said that a pool used by 1000 people contains about 75 liters of urine. Trichloramine can cause red eyes. It's also said to be carcinogenic. So, with all that said, I'm never going to a pool again.