If you enter a swimming pool and you can still smell chlorine after 1 minute, or if your eyes sting, then you should not use the pool.
Ask the pool operate what the Pool Performance Factor is, this should be less than 2.
If the performance factor is above 4, or if there is the smell of chlorine, the gas is not actually chlorine but a by-product of chlorine. Swimming pools should not smell of chlorine, if they do then the noxious gas can damage the mucous linning on the lungs of children and cause a sensitized response that can lead to respiratory problems and asthma 10 or 20 years latter.
So if you use a pool, do not eneter unless the Performance Factor is under 2. And if you smell chlorine, or if the water irritates you eyes, then do not allow children under 2 to enter the water.