Risks of swimming with FC above 4?

[fastrunnerdude]

I've been using TFP methodology for 4 or 5 months and it's going well. My CYA was on high end due to almost a year of the pool guy using pucks. It's gradually coming down (currently around 50) as it's diluted with rain and I drain off some water after heavy rains. According to the pool math app, my target FC range is 4 - 8 though I've been keeping it around 3 - 4.

I often see recommendations that free chlorine should be somewhere between 1 - 4 ppm and it can be dangerous to swim if too high. Are there issues with chlorine levels of 6 - 8? Do the guidance and warnings not account for CYA levels and assume it's low or 0?

 

[V___25]

FC of 1-3 is a pool store recommendation and generally not a good idea. 4 is the really the lowest FC should ever be in TFP world. At a CYA of 50, your target FC is 6-8 according to the CYA/FC chart. It's safe to swim up to SLAM levels.

 

[ajw22]

I often see recommendations that free chlorine should be somewhere between 1 - 4 ppm and it can be dangerous to swim if too high. Are there issues with chlorine levels of 6 - 8? Do the guidance and warnings not account for CYA levels and assume it's low or 0?

Correct. The 1-4 ppm chlorine guidelines are without any CYA in the water.

Read CYA Chlorine Relationship - Further Reading to understand the buffering CYA has on chlorine and the low amount of active chlorine that the proper FC/CYA ratio has.