We just refilled our pool and hot tub and the CL was up at 27. My wife really wanted to go in the hot tub so I heated it up and we jumped in. We did rinse off after and I don't think I would want our kids in water above 10. I personally have been in our pool when it was about 50 and I am still pretty normal If in doubt about high CL levels rinse before and after, I have found you soak up less CL smell if you’re already wet and obviously rinsing after helps a lot.