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Old 22-11-2013, 05:55   #46
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Re: Hull Cleaners Thrown Under The Bus

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Here's my big problem with the study. Sample collection was done with a device that is supposed to approximate a human performing in-water hull cleaning. A spring-loaded, hand-cranked scrubbing cylinder? That is what the entire study is based upon. But since the CPDA was not allowed to witness the study or see any of the data as it was being collected (we asked and were rebuffed), who the hell knows if the device actually performed as advertised. It is entirely possible that the sample collection methodology was completely flawed (perhaps intentionally) since no hull cleaning professionals (or anybody else who has ever cleaned a boat bottom) were allowed to participate in the study or witness the device's use.
This the only thing close to a justification for not taking the study as valid but it's still a weak arguement.

It's common practice to replace human interactions with a mechanical device to ensure the test is consistent among the options. This actually supports the test as being valid.

The fact that you weren't allowed to be at the testing proves nothing. If I go to the feds and demand to watch vehicle crash testing, they will laugh at me also and tell me to go away. Unless you have proof of fraud, you are treading close to slander against the research institutions.
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Old 22-11-2013, 06:05   #47
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Re: Hull Cleaners Thrown Under The Bus

While yes, a mechanical device would ensure "consistency," if 80K instances of cleanings per year are indeed being performed then it would have been quite simple to get a representative sample from actual boat cleanings.
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Old 22-11-2013, 07:35   #48
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Re: Hull Cleaners Thrown Under The Bus

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if 80K instances of cleanings per year are indeed being performed then it would have been quite simple to get a representative sample from actual boat cleanings.
Which is how at least one previous study obtained its data. A study, which BTW, showed that the copper contribution from in-water hull cleaning was only 5% of the total.
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Old 22-11-2013, 08:23   #49
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Re: Hull Cleaners Thrown Under The Bus

I am as jaded as they come, but before I would call a study bogus, I would want to see the test parameters that were used. You are entirely right they can tailor these studies to the degree that if shows exactly what you want to see. So unless there is a way to get your hands on the study parameters, there is no way to know how valid it is. A good study would have a baseline of data to work from like setting the mechanical scrubbing device to the median pressure exerted by x number of human boat bottom scrubbers. How much per square inch pressure is being applied? Once that is determined then is there documentation to support that the mechanical scrubbers were calibrated to the same pressures? An so on and so forth.
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Old 22-11-2013, 08:52   #50
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Re: Hull Cleaners Thrown Under The Bus

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I ask you one more time to just shed some light on where the study is flawed.
Well, for one thing it ignores the fact that the paint functions by releasing the copper - it is the active ingredient. If fresh copper isn't exposed / leaching, then it isn't preventing growth either. Which is another aspect that I didn't see mentioned in the study (although I only scanned the report) - it didn't mention growth or effectiveness of the paint on the samples.

The whole purpose of ablative paint is to expose fresh paint (i.e. copper). So if ablative paint (or the boat it's on) isn't "used" then it won't work properly - is a test sample left to sit still representative of how the paint is meant to be used? Final comment, I don't believe you are supposed to clean ablative paint often (it is the action of the water over the hull that is supposed to "clean" it). Harder, non-alblative paint is for higher speeds and more frequent cleaning.

I have to get going, but hopefully you get the point.
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Old 22-11-2013, 09:21   #51
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Re: Hull Cleaners Thrown Under The Bus

Studies and statistics are all about what question was asked in the first place. Ask a question the right way and you get the answer you want.
Having said that, I think It's pretty obvious from cleaning my own bottom that disturbing the paint puts a lot of it in the water.... especially with sloughing paints.
How bad is it really? I have no idea... it's often hard to tell the real effect on the environment. Govt angencies are not known for practical decisions. I've worked on projects where the natural heavy metals in the soil exceeded the EPA limits for waste. Same for incoming city water exceeding the PH limit for outgoing water!
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Old 22-11-2013, 11:44   #52
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Re: Hull Cleaners Thrown Under The Bus

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Well, for one thing it ignores the fact that the paint functions by releasing the copper - it is the active ingredient. If fresh copper isn't exposed / leaching, then it isn't preventing growth either. Which is another aspect that I didn't see mentioned in the study (although I only scanned the report) - it didn't mention growth or effectiveness of the paint on the samples.

The whole purpose of ablative paint is to expose fresh paint (i.e. copper). So if ablative paint (or the boat it's on) isn't "used" then it won't work properly - is a test sample left to sit still representative of how the paint is meant to be used? Final comment, I don't believe you are supposed to clean ablative paint often (it is the action of the water over the hull that is supposed to "clean" it). Harder, non-alblative paint is for higher speeds and more frequent cleaning.

I have to get going, but hopefully you get the point.
Big difference between slow leaching and the cloud of copper released thru scrubbing.
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Old 22-11-2013, 13:25   #53
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Re: Hull Cleaners Thrown Under The Bus

My question is how dangerous is copper? At very low levels it is an essential, human micro-nutrient but at high levels it is toxic.

So at the concentrations in the water, even areas around marinas like the Bay, are the levels high enough to be an environmental concern?
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Old 22-11-2013, 14:35   #54
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Re: Hull Cleaners Thrown Under The Bus

Adding my 2 cents. I don't believe that the study will make any difference in the end to the frequency of needed hull cleanings. The amount of growth which develops and the required cleaning intervals are what they are. The amount of copper in the water is what it is.

The study shouldn't make any difference in your ability to make a living and the necessary frequency of hull cleanings, it's just another way California has discovered to waste money on useless studies. What next? Some California knitt-witt eco legislator will probably try to regulate the speed which marine organisms will be allowed to grow and attach to hull bottoms?

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Old 22-11-2013, 16:29   #55
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Re: Hull Cleaners Thrown Under The Bus

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In California, the fouling rates are such that regular hull cleaning is a necessity (regardless of what the paint companies would have you believe.) Copper paints pollute and to a lesser degree, so does hull cleaning. Lets assume copper paints are not going to go away. What is the state going to do, ban hull cleaning? That leaves the boat owner with one alternative- haul the boat at a yard to have the bottom cleaned. Is that convenient? Is that cheaper than a diver? Is it less polluting than in-water hull cleaning? I say the answer to every one of those questions is no.

Yes, I am concerned about my livelihood. But the boat owner should be concerned as well- about the cost, availability and ease of obtaining the hull maintenance his boat needs.
So I am assuming the gubberment will regulate the amount of hull cleaning a year. I believe in a former thread you may have suggested a cleaning every 2 months (correct me if I'm wrong). So how many hull cleanings a year would be allowed?
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Old 22-11-2013, 16:43   #56
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Re: Hull Cleaners Thrown Under The Bus

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My question is how dangerous is copper? At very low levels it is an essential, human micro-nutrient but at high levels it is toxic.

So at the concentrations in the water, even areas around marinas like the Bay, are the levels high enough to be an environmental concern?
E X A C T L Y!
Is it worse or better for organisms than the tons of oil washed into the bay from parking lots and streets?
I'm an enironmentalist at heart, but I just dont get the powers that be... when they pick on little things and ignore the big things.
SUch as: The oil mentioned above. The millions of tons of raw sewage let into the water by municipalities because "the rainfall exceeded what we could handle in the sewer plant" (does anyone get how rainfall and the sewer plant are related?)
How about the bilges of large tankers spreading animals that destroy local ecosystems? Heck... I've been on airplanes where when you land in acountry, a person walks down the aisle before you deboard and sprays some sort of insecticide all over! (Samoa!) I would think tankers could be required to kill everything in the bilge before they enter.
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Old 22-11-2013, 16:53   #57
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Re: Hull Cleaners Thrown Under The Bus

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E X A C T L Y!
Is it worse or better for organisms than the tons of oil washed into the bay from parking lots and streets?
I'm an enironmentalist at heart, but I just dont get the powers that be... when they pick on little things and ignore the big things.
SUch as: The oil mentioned above. The millions of tons of raw sewage let into the water by municipalities because "the rainfall exceeded what we could handle in the sewer plant" (does anyone get how rainfall and the sewer plant are related?)
How about the bilges of large tankers spreading animals that destroy local ecosystems? Heck... I've been on airplanes where when you land in acountry, a person walks down the aisle before you deboard and sprays some sort of insecticide all over! (Samoa!) I would think tankers could be required to kill everything in the bilge before they enter.
Exactly!...I was living in the Alameda estuary last year and after a good rain all the crap from the storm drains would wash into the water. There was always a good oil slick, some syringes and a few condoms (nice touch). So my point is...the cities and state should clean up their own mess (though their bad design) and then see what the numbers look like.
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Old 22-11-2013, 17:12   #58
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Re: Hull Cleaners Thrown Under The Bus

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Right. You're saying the paint manufacturers ponied up $160,000 to produce a study, the outcome of which they were unsure of? What, they just got lucky on this one? Bwahahahaha!
Yeah right!!! Its similar to the old legal posture " don't ask the question if you don't know the answer!" I cannot believe they would spend money that could result in harm to their business.
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Old 22-11-2013, 17:17   #59
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Yeah right!!! Its similar to the old legal posture " don't ask the question if you don't know the answer!" I cannot believe they would spend money that could result in harm to their business.
What happens is that if a study results in a conclusion the funders don't like, then it does not get released.

The studies that are released are legit... they just happen to coincide with the funders interests.
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Old 22-11-2013, 17:18   #60
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Don't most marinas have wash off filtration. We can't open air sand anymore. That probably makes sense. I would love to be able to free sand grind with a big 36 grit and no vac. It's better that I have this dink sander and vacuum and try not to contaminate everything around me. Sucks at the moment but it makes sense .
I can tell you when I scrub in the water I am scrubbing copper. It is visible and after a bit I can taste it. It has to be better to rinse off at a marina with filtration then scrubbing in the water .
Maybe we can come up with a universal bottom paint that keeps divers employed and works. We could call it ohh bottom care.
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