Cyanurics ~

[Heavyhook]

Thanks everyone for clarifying what was going on with regards to Kent Williams. As stated before I was mearly trying to share some information I thought might be helpful. While searching the WWW I ran across his article , and thought the graphs that were included would be helpful to other as it has been to me in understanding how CYA and Chlorine work together(only to find out there is no science behind them).
One thing I guess I forgot is just because something is published on the net does not make it true! And To find out that someone has created a Persona with their own credentials by establishing the" POOL" origination, if it really exist. And naming them self president to give legitimacy to their cause is something I never expected.
I'm glad there are members here with the experience and knowledge to know the difference. I have only owned my pool since the end of May and have relayed on INTERNET sources in this short time, instead of pool stores to educate myself on its operation and care.
Unfortunately in a Capitalistic Society this happens all to often and is not limited to Pool service/supply company's. Auto Repair/Maintenance, Plumber's, construction contractors, insurance sales persons etc. are only a few examples. Its just another example of how uneducated consumers get taken advantage of. Everyone in these professions are not all self serving but enough bad apples exist to give entire parts of their respective industries a bad name. Many our chasing every dollar that can be taken from the unwary consumer.
I have enjoyed reading the Forum and appreciate your efforts to keep the shysters out, Thanks Doug

[chem geek]

I have a post on Pool Water Chemistry in The China Shop that has some graphs based on the chemistry determined back in 1974 when the chlorine/CYA relationship was definitively determined. However, the graphs on CYA's protection of chlorine from breakdown from sunlight make assumptions that we have since found to be incorrect. Namely these graphs do not take into account that there is an additional CYA protection effect by shielding lower depths from UV -- not just from binding to chlorine to make it more stable. Also, the graphs I made on chlorine breakdown in sunlight use Kent Williams' data for the presumed rates of breakdown of chlorine bound to CYA from UV in sunlight and those rates may be incorrect.

I also have a link to an ORP post that shows the fallacy of using ORP for absolute measurements. It can be OK to use for process control to maintain an FC level by using an ORP mV "setpoint", but that's about all. (Ben, if you could allow the "CODE" to work again in vBulletin, that will make some formatting work better -- also, if vBulletin allows for subscripting and superscripting, that would be helpful as well).

I wrote E-mails to Kent Williams at PPOA in 2004, 2006 and 2007 and never received any response. My comments with regard to Kent Williams' paper and commercial pools are limited to his suggestions regarding the importance of supplemental oxidation due to the high bather loads in such pools and have nothing to do with the chlorine/CYA chart which applies to the chlorine levels needed to prevent algae in ALL pools. The oxidation of bather waste, particularly urea, can be very slow if there is no exposure to UV or higher water temperatures (i.e. spas). So indoor pools and high bather load pools can benefit from supplemental oxidation not only to oxidize faster but also to help prevent disinfection by-products (DBPs) which virtually every scientific paper shows to be mostly proportional to bather load. Though one could raise active chlorine levels (either raising FC or lowering CYA to raise ORP) for faster oxidation as he proposes, one could increase DBPs by doing so.

Richard