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Excess Splashing When Flushing/Adding Water and Backflow Prevention

I am doing some work with a plating shop and in the course of one of our weekly meetings it was determined that there was a problem with excess splashing when filling a tank (bath or rinse). This results in plating baths getting into the scrubber vents, possibly creating unnecessary loading on the scrubber system and also spilling to the floor, creating more wastewater for the treatment plant.  The current set up of the influent water lines utilize an air-gap to protect against backflow. Herein lies the problem I suppose. If the air gap is eliminated, we would have to resort to installing reduced pressure zone (RPZ) backflow prevention devices, as I believe these are the only devices approved for hazardous substances other than air-gaps. Does anyone know of a method that would allow us to continue using the air-gap, but to minimize or eliminate the splashing? Failing that, would we need to install RPZs on each water line for each tank or just one on the incoming water line into the plating area?

Thanks in advance for all responses!

Derek Burton
Plating Shop - Atlanta, Georgia, USA
2004

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Not having seen your installation, I cannot guarantee that this will help enough, but can guarantee that it will help: cut the pipes at a diagonal. Cut them at at least a 45 degree angle, preferably more than that. Everyone will be quite surprised how smoothly the water exits a pipe that is cut diagonally instead of straight across. Let us know what you think after you've tried it.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004