Please ignore the CPO guidelines -- the info here is *much* more up-to-date. Chem_Geek, who started here in 2000 or 2001, has repeatedly tried --without much success -- to get the NSPF (behind the CPO) and the NSF to update their standards to reflect the work of Obrien (1972, I think) and Wojitowisc (circa 2000) and his own extensive analysis published here, on his personal home page, and elsewhere. (Wojitowisc' journal article in the JPSI was what gave me the confidence to publish my own observations in the first Cl-CYA page, which I called the "Best Guess Chart".

At this point in time, I'm pretty confident that Chem_Geek knows more about pool chemistry, from an comprehensive analytical view, than anyone else in the world. (Ernest Blatchley at Purdue is doing great work, but doesn't know about pools overall.) Add to that 10,000's of pool owners confirming not only my Best Guess chart, but Chem_Geek's analysis . . . and the CPO and NSPF are decidedly 'behind the times'.

But, given the fact that 'doing it right' would cost the pool industry literally $100,000,000's per year, their incentive to 'fix' things is small!