Swimming at shock level.....

[gtnos]

I know the consensus is that its safe to swim up to shock level. Does that mean if my shock level is 17, i can swim at 17, and just not at 18+?

also, what would happen if you swam at over shock level? Chlorine will just dry out your skin or what?

 

[jblizzle]

sshhhhhhhh ... it is still safe over shock level, within reason ....

The higher your FC relative to your CYA, the more active chlorine in the water and thus the more harsh it is to your skin, hair, swimsuit, etc.

Check out this chart that shows the active level as a function of CYA and FC. You can draw your own conclusions about what is a "safe level" of FC when you remember that a public pool with 0 CYA often has a FC up around 2ppm.
https://www.troublefreepool.com/~richardfalk/pool/HOCl.htm

I will give an example:
That public pool would have an active chlorine level of around 1.00ppm
At CYA 50, normal FC level is 6, giving an active chlorine level of 0.05ppm (1/20th as harsh as the public pool)
At CYA 50, shock level is 20, so active chlorine level is 0.30ppm (1/3 as harsh as the public pool)
At CYA 50, to match the active level in the public pool, the FC would need to be up around 30ppm probably.

 

[tim5055]

I know the consensus is that its safe to swim up to shock level. Does that mean if my shock level is 17, i can swim at 17, and just not at 18+?

also, what would happen if you swam at over shock level? Chlorine will just dry out your skin or what?

Actually even over shock level (within reason)it is safe for normal skin. It is bad for people with skin conditions and is really harsh on your swimsuit.

 

[R.J.]

I had to patch a hole underwater when the pool was above shock. I was in less than 10 minutes, and about 30 minutes later my skin felt dry and somewhat itchy. I say "somewhat itchy" because while I wasn't scratching all over, my skin felt like I had been wearing wool clothes. I don't really know how to describe it, but I certainly won't do it again unless I absolutely had to.