Quote Originally Posted by badabing View Post
I know I can reduce it further (Which I promptly did to 15%), but I'm concerned that when generating chlorine, it generates too much ie too concentrated in small bursts that it could effect the swimmers in the pool.

Are my concerns warranted?
It's not going to affect swimmers, especially with the higher CYA levels. It might affect swimwear.

Because I used to operate commercial pools with pumped industrial bleach feed, I worried about this issue on occasion, and even tested the chlorine level in the water returning to the pool, which was high. But it mixes and dilutes VERY rapidly. It's possible I put a bleach spot on someone's suit, but in 20 years of operating 10 - 30 large commercial (>100,000 gallons) pools, with hundreds of users daily at each pool, I never had a report of a problem. That doesn't prove there wasn't one, but it suggest that if it occurred (a) it wasn't common and (b) it wasn't too serious.

I've semi-seriously joked over the years, that if the chlorine in your pool is too high, you should just swim naked. But, it's true that skin is FAR less affected by chlorine than is Lycra swimwear and many dyes in plain nylon or polyester suits. That information came from my own observations and experience, not from scientific or medical literature. But this spring, I found that dermatologists have for years been prescribing something called "bleach baths" with patients soaking in a tub of water, with chlorine levels of 50 - 100 ppm -- and that this treatment is STILL currently used. (Google search for "bleach bath"). So, it turns out that there IS medical confirmation of my observations.

There is a fairly common scenario, that is outside the realm of polite conversation, but which could lead to some mild skin irritation and some serious swimsuit damage: using a pool return jet for masturbation. Over the years, I've often heard guys joke about this, and I can recall some comments made by some friends when I was a teen. And, there have been several cases of teens or men getting themselves 'caught' in a pool return that had the eyeball removed. I also once observed an adult woman using a pool return to masturbate, in a otherwise unoccupied pool (I'll try to convince you I wasn't perving: I'd had to make a service call, and came in the back entrance which required me to walk outside the natatorium tinted glass -- it was night; she couldn't see out, and normally there was no traffic on that walk even in day. It actually took me about an hour after I saw her, to work out what she was doing -- it looked strange, but I didn't immediately recognize what was going on.) Anyhow, in THAT scenario, some one could white-spot the groin area of their swim suit pretty noticeably, and could end up with some 'chapped' skin. Obviously, there are no statistics on how common this is; but it's certainly not uncommon.

Other than that situation, I don't think problems are likely.

I did cover the data I have on high chlorine effects on people, in this thread: http://www.poolforum.com/pf2/forumdisplay.php?156