Is swimming safety relevant to cya/chlorine ratio?

Poppylocks

Member
Jul 12, 2019
5
New Jersey
Ok, so again, you guys have all been so helpful. Swamp pool is back to clear. I have had a crash course in pool chemistry and am getting the hang of it. Where I do have some confusion is if the CYA is higher and the target chlorine level therefore is higher, when is it safe to swim? We had a CYA level of 160 🤭. We drained and refilled some (trying to do little by little as not to kill our pump since we have well water), and I got a reading of 80 yesterday so progress. Actually have to grab more reagent for that because I used both bottles already...anyways free chlorine was 12.4, ph 8, TA 80, CH110.

On the pool math calculator it says target level is 6-11ppm for a CYA of 80. When can you swim? I thought it has to be around 4ppm to swim? I’m still refilling about another 6 inches and am running out today for the cya regaent to recheck but I have little minions who are dying to get in the pool. Can you elaborate on when it’s ok and once I do reach target level what should I do daily to maintain it? As a kid I swear my parents used to just toss in a cup of bleach everyday and skimmed the pool. It seems so complicated to me now!

Thanks everyone.



Tl;dr is swimming safety relative to the cya/chlorine ratio Higher cya means higher free chlorine needed but does that make safe swimming ok at those higher levels (6-11ppm)
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,404
Laughlin, NV
You can safely swim in a pool as long as the FC is above the minimum and at or below SLAM level based on your CYA. You must also be able to see the bottom of the pool in the deep end of the pool.

SLAM level FC for a CYA of 80 is 31 ppm. So it is safe to swim up to that FC level.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,404
Laughlin, NV
For daily FC maintenance, test FC and then add enough liquid chlorine to reach the target range for your CYA. Be sure your FC never drops below the minimum FC for your CYA level.