Certified Pool Operator (CPO) training -- What is not taught

chem geek

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thepoolpros.com said:
as far as the breakpoint calcuation, it has become very unclear between different editions. The best description/explanation I have read is on Robert Lowry's Pool Chlorination Facts where he talks about multiplying the combined chlorine by 7.6 to determine the correct amount of FAC to add to reach breakpoint. Dr Lowry's books can be purchased on his website http://www.lowrycg.com/book.php

We can all make suggestions to the NSPF by emailing tom.lachocki@nspf.org . He is the CEO, and a very good one at that.
I have Lowry's book and responded to him with comments on it in 2007 since not everything in it is accurate. As for breakpoint chlorination, if you read the section on this I wrote in the first post, you will notice a link to this post which shows you where the 7.6 factor comes from and why this formula is misapplied and used incorrectly for Combined Chlorine (CC).

As for NSPF, I've had E-mail conversations with Tom Lachocki and sent him the file of my suggestions and I've also met him personally at last year's NEHA conference. He's a nice guy and very competent, but has not (to my knowledge) changed anything in the CPO course with regard to my recommendations such as including the factual chemical side effect tables (which is not controversial at all) or the hypochlorous acid tables when CYA is present, etc.
 

chem geek

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CaOCl2 said:
I think Lowry came up with the concept that your FC should be 10% of your CYA.
Are you sure about that? I didn't see anything like that in his Pool Chlorination Facts. I believe Ben Powell was the first to come up with his Best Guess CYA chart (it was created before 2006, the date of that post, as the site had crashed and been reconstructed) and there's a date in the post of July, 2003 and the PoolSolutions website seems to have been created around 1997. The idea of the FC being a proportion of the CYA for the same active chlorine level comes directly from the known chemistry, but the actual algae inhibition level is something one can only determine through observation or experiment.
 

CaOCl2

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(CYA should be) "preferably 8-10 times the free available chlorine" is the actual quote. Couldn't find anything relating to the Best Guess Chart on the Wayback Machine from that era. Not saying it ain't there, just saying I couldn't find it.
 

chem geek

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Now that I have the book in front of me, I see the full quote and context of the statement. The statement is in the section on "ORP and Free Chlorine Probes with Cyanuric Acid" after talking about the ORP probe sensing only the unbound chlorine when cyanuric acid is present. There are plenty of incorrect statements made, but I'll get to that in a moment. Then he writes the following:

For cyanuric acid to work we need a certain amount in the water (preferably 8-10 times the free available chlorine) to protect the chlorine from UV light. This is enough to have 95% of the chlorine attached at any one instant.
So the context here is about having enough CYA in the water to bind to enough chlorine to protect most of it from sunlight. There is no discussion about this being the amount needed to prevent algae growth. In fact, this entire section has a lot of incorrect information as he talks about the chlorine bound to CYA as being active:

When both free chlorine and cyanuric acid are dissolved in the water, part of the chlorine is attached to the nitrogen atoms in the cyanuric acid. The ORP probe cannot sense the active chlorine attached to the cyanuric acid therefore, this part of the active chlorine does not contribute to the ORP reading. But the free chlorine test reagent (DPD, syringaldazine or TMB) does sense the chlorine attached to the cyanuric acid because it is so weakly attached.
:
Chlorine that is attached to cyanuric acid is still active chlorine. The proof is that when you do a free chlorine test with cyanuric acid in the water, the chlorine shows up as free, not combined.
:
If the attached and unattached chlorine reacts with the free chlorine test reagent, it will also react with anything that is oxidizable (bacteria, alage, swimmer waste, etc.).
This is, of course, completely wrong logic since the free chlorine test just measures the amount of chlorine that is potentially available to become active, that is it includes the chlorine in reserve (bound to CYA and technically includes hypochlorite ion as well), but this is NOT the same thing as the concentration of truly active chlorine (hypochlorous acid) that determines reaction rates.

I've used an analogy of front-line soldiers as active chlorine while those in reserve are inactive. It doesn't matter how many soldiers you have in reserve nor how quickly they replace a fallen soldier on the front-line, the rate of killing is solely determined by the number of soldiers on the front line. His logic regarding the further reacting of the DPD dye is false because that reaction is very fast so obscures the fact that the rate of that reaction is determined only by the amount of active chlorine unbound to CYA (specifically, hypochlorous acid). If there were no CYA in the water, the reaction would occur orders-of-magnitude faster, but for the DPD test the difference between taking 1 second vs. taking 0.05 seconds doesn't matter. However, for killing pathogens that take longer to kill, it does make a difference as it does for the rate of killing algae. In a later section on page 119 under "Cyanuric Acid and ORP Readings" he writes:

If the cyanuric acid was really slowing down chlorine's oxidizing ability we would expect the reaction of chlorine in the water sample to take longer to react with the reagent or to not react with it at all, indicating it was combined. But it doesn't.
He again doesn't realize that in fact the reaction IS slowed down, but not by enough to notice. The half-life of chlorine bound to CYA producing more hypochlorous acid is (for the fastest reaction path) 0.25 seconds so assuming the reaction of the dye with chlorine is very fast, when CYA is present the chlorine test will be essentially complete in a matter of seconds, regardless of how high the CYA level (until it got to a point where the active chlorine concentration was so low that it was very slow to react with the dye -- that could be a huge CYA level before that happens).

I see that in the section "The Proper Amount of Cyanuric Acid" on page 117 he writes:

Experience has found that it takes 10 ppm of cyanuric acid in pool water to protect up to 1.5 ppm chlorine in the water. Any amount of chlorine in excess of 1.5 ppm in the water when you have 10 ppm of cyanuric acid is not protected. It is then subject to sunlight destruction at the rate of 90-95 percent in 2 hours ... Depending on water conditions, it will take about 8-10 times as much cyanuric acid as free chlorine to be effective.
This simply isn't true. There isn't some sort of magic cutoff for this protection. The rate of breakdown of chlorine is a function of how much is bound to CYA vs. how much is unbound and it is simply not true about the "excess" amount not being protected. The amount that is unbound is proportional to the FC/CYA ratio so he does have that relationship understood correctly, but it doesn't mean more chlorine isn't protected. At 3 ppm in the water with 10 ppm CYA there is NOT 1.5 ppm unprotected -- there's somewhat more than 2.5 times as much unprotected (0.33 ppm vs. 0.13). And even that's not quite true since the chlorine bound to CYA breaks down as well, just not as quickly. And then there's the CYA shielding of lower depths that he is ignoring (though we only discovered that ourselves rather late).

Now that I have the book in front of me I see all of the notes I wrote in it about the things that were wrong. To his credit, Bob Lowry did understand the bound vs. unbound chlorine/CYA relationship, but he gets a lot wrong thinking the bound chlorine was active and thinking that CYA protecting chlorine from sunlight had hard limits rather than being driven by proportions determined by equilibrium chemistry.

So the 8-10 times of CYA to FC has nothing to do with algae prevention and using his logic that the bound chlorine is active it is the FC alone that should determine algae prevention. So he really didn't come up with the appropriate chlorine/CYA chart for algae prevention though he accidentally came up with something in the ballpark (though in a backwards sort of way) by thinking of CYA protecting FC from sunlight.

Anyway, the Pool Chlorination Facts book is 7 years old and Bob Lowry is now updating books he has written for IPSSA (the Basic and Intermediate Training Manuals on Water Chemistry), but I haven't had a chance to thoroughly review those yet.

So, again, as far as I know, Ben Powell is the first to determine the chlorine/CYA relationship with respect to levels needed for algae prevention. His Best Guess CYA chart doesn't exactly match constant FC/CYA ratios (or more specifically, calculated hypochlorous acid concentrations), though for the Min and Max it's reasonably close above 30 ppm CYA as shown here though shock levels don't track as well. His chart was created mostly from his experience with real pools.
 

JasonLion

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The earliest occurrence of "Ben's 'Best Guess' Chlorine Adjustment Table" I can find is from June 21 2005, here. He may well have published it earlier in his newsletter, but those are not archived on-line.
 

waste

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Re: Certified Pool Operator (CPO) training -- What is not ta

Ok, I'm trying to digest the chemistry side of this :)

Next week I take the course and will add field reports, as applicable.

Even though this was started as an issue with the chemistry they teach, I've (from a quick glance at my handbook) noticed that they spend a good bit of words talking about how to build a pool, where the backwash is going and other things that a CPO, coming in to an existing pool, has NO control over. (if the pool wasn't built to code, it wouldn't have been allowed to open)

My handbook is also the 2009 version.

I'll keep y'all informed as to my experience (as long I don't kill the instructor and get kicked out :lol: )

UPDATES NEXT WEEK :goodjob:
 

AClogston

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Re: Certified Pool Operator (CPO) training -- What is not ta

I take mine on the 26th of this month, but I did the fusion course (online course + 1 day of class). The online portion covers the entire book, and they definitely skim over most of it pretty quickly.The sections on pool building, etc. are covered in two or three bullet points. It is a good base of knowledge, but I feel I learned more about the nitty gritty of pool operation here. In fact, when I first corresponded with the head of our state Public Pool and Spa Program the first reference he told me to look at was TFP.

Good luck on your test!
 

waste

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Re: Certified Pool Operator (CPO) training -- What is not ta

Alex, I've been wanting to talk with you :)

I used to live in Lin-Wood and worked for Indian Head, the Red Doors, Mt. Club @ Loon, et. al. :-D It's nice to see someone who I can relate with re. the neighborhood :thumleft: :cheers:


I'm not worried about the test!

What I'm more worried about is getting kicked out of the class before I get my CPO :mrgreen:
 

AClogston

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Re: Certified Pool Operator (CPO) training -- What is not ta

Wow, what a small world!

I'm sure you're familiar with the Mill House Inn then (currently South Mountain Resort)? That would be where I work. Though I've frequented many of the pools you mention :)

Well, good luck not getting kicked out, and if no instructors get killed in the process that's just a bonus.
 

waste

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Re: Certified Pool Operator (CPO) training -- What is not ta

Field Report (part1 --?)

I'm trying to digest what was taught over the past 2 days - I went in with years of experience and knowledge, some of what was presented was, to some extent, contrary or conflicting with what I 'know' from experience or what I've learned from here and PF.

I realized yesterday that there was an issue I hadn't thought of... CPOs work with public or higher use pools than are usually the case on this forum. I've seen disclaimers in some of Richard's posts saying that ~'this is for residential pools', or similar and am trying to adjust my thinking/ preconceptions to include that.

That said-

They are VERY good with how to keep records (to keep litigation/ liability down)!

A quick glance at who (& what companies) made up (wrote) the book (and corresponding chem suggestions) shows 3+ pool chemical companies 'flacks' :evil:

There was some mention of going with a 'less expensive' chlorine/ chemical source (but that wasn't in the book, just from my instructor).

Many good points/ ideas about keeping the property and pool area safe for employees and users!

They still hold to the Langlier Saturation being kept to +/- .3 [not that it's horrible] (chem company's input? :roll: )

I learned why pH is a factor in effective chlorine (the HOCL v.s. OCL- interchange)

--------------------------------------------------------------------------------------

More to come but, I'm f** exhausted (and my wife wants me to come to bed :wink: :cool: )
 

chem geek

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Re: Certified Pool Operator (CPO) training -- What is not ta

waste said:
I learned why pH is a factor in effective chlorine (the HOCL v.s. OCL- interchange)
Yes, but they don't teach how this changes when CYA is present. Show them my Table 5-2 and 5-3 on page 6 of my comments document or show them the graphs in this post that shows that 1) the active chlorine (hypochorous acid) level is far, far lower when CYA is present and 2) pH has a much smaller effect on this active chlorine concentration when CYA is present. CYA acts as a hypochlorous acid buffer resisting changes in its concentration when the pH changes. Whereas the active chlorine concentration drops roughly in half going from a pH of 7.5 to 8.0 when there is no CYA, it only drops around 14% when CYA is present.

As for commercial/public pools, there are some differences, but I took that into account in my comments document for the CPO course since I knew that much of what was in there was for such pools. Also ask your instructor why non-controversial chemical facts such as I show in in Table 5-5 on page 10 are not taught in the CPO course. Wouldn't it be useful to know how to EASILY calculate how much CYA and CH are added by Trichlor, Dichlor and Cal-Hypo by simply knowing your daily FC usage? Yes, with commercial/public pools there is water dilution so one must take that into account, but most people don't realize how quickly CYA can build up from Trichlor. In a commercial/public pool one can easily have 5-10 ppm FC per day from bather load and that translates into 90-180 ppm CYA increase per month if there were no water dilution. Of course, most such pools use chlorinating liquid, but there are still many inline chlorinators at hotel pools and other commercial installations.
 

waste

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Re: Certified Pool Operator (CPO) training -- What is not ta

Thanks for responding Richard! :bowdown:

I had 2 pages printed out with your 4 graphs of "% of FC vs pH with..." :cool: but, I wasn't there to start an argument, and talking with 1 instructor wouldn't make them change their minds, nor opinions :evil:

I notice, on those graphs, that you include a TDS level - is it more important than I think/ believe? (the course says it's an indicator of a problem, but is it really, when we follow the methods and chemistry advocated here?




Just to throw one other thought out here, this is a course offered by the NSPF and, as indicated in my previous post, has pool chemical manufactures as part of it. I fear that the info they dissemble is skewed by THE BOTTOM LINE :pukel:

The state of Maine has NO(!!!!!) other way to be certified (unless you passed the Canadian version of the course) - it's a F^&% monopoly on certification :evil: (you have to be re-certified by them every 5 years, which I think is why the state doesn't have it's own test)

I'm not a conspiracy 'flake' but, I DO believe that the NSPF has 'influenced' the legislature, of the state of Maine, so that - they are the only ones to certify CPOs. (a state given test, for folks operating public pools, should be available!!!)

Yeah, I'll march on Augusta first thing tomorrow :lol: (jokes aside, I think it's BS :!: that private companies can 'make' the laws, despite better info being available here :twisted:
 

chem geek

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Re: Certified Pool Operator (CPO) training -- What is not ta

waste said:
I notice, on those graphs, that you include a TDS level - is it more important than I think/ believe? (the course says it's an indicator of a problem, but is it really, when we follow the methods and chemistry advocated here?
The TDS is not important, but it slightly influences the numbers so to be precise I listed it since the calculations were based on it. For the graphs of chlorine vs. pH, it's certainly not a big deal at all.
 

waste

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Re: Certified Pool Operator (CPO) training -- What is not ta

Thanks again, Richard! :bowdown:

(I typed and THOUGHT I'd posted this last night .... but it's not here :? )










Today I got my test results and ....................... (of course :wink: ) I got 100% :party: :whoot: :cheers: .

(This brings me to them 'spoon feeding' 50% of the answers - they design the course for people to pass - there was NO help given, on answers, during the test) However, we were told to highlight certain sentences in the book and remember them for the test :evil: Yeah, it makes the test easy to 'ace', but, has anyone REALLY learned the material?

I've seen this in EVERY certification 'course' I've taken, in the pool industry :grrrr: They give you a precursory ("complete") overview of 'whatever' issue is at hand and then ask you a few obvious questions about what you just learned and certify you. Once you pass the 'test' you are an expert. :hammer: :grrrr: :evil

I am SO glad I found PF (and then this site) so that I can now:

1) KNOW the truth (& have a source for asking questions that the industry won't answer honestly)

2) Care for the pools under my supervision in a way that will keep the users safer!

3) Continue my education to 'keep up' on doing as I have
 

chem geek

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Re: Certified Pool Operator (CPO) training -- What is not ta

Congratulations on becoming a Certified Pool Operator (CPO)! :party: :goodjob: :whoot: :cheers: :punkrock: :rockon:

Until now, you've just been a poser! :hammer: :gone: :rant:

Seriously, I'm glad you went through it so that an obstacle has been removed for you to be able to satisfy more customers with their pools.
 

AClogston

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Re: Certified Pool Operator (CPO) training -- What is not ta

Congrats on completing the course, and on everyone surviving!

Turns out the class I was looking to take got canceled, now I have to locate another one before my certificate from the online course expires. I see much driving in my future...