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Curated with aloha by
Ted Mooney, P.E. RET
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Chlorine bath of G60 coated parts
Q. We manufacture structural parts with a G60 galvanize finish. Recently, a customer used a chlorine solution to spray mildew from the walls of their unfinished house.
Can anyone tell me the long-term effects of a chlorine bath on a G60 coating?
This is in Florida, so humidity will be high, throughout the life of the product, even though exposure to chlorine was a single bath.
Thank you, bob lutz tampa
Robert W. Lutz- Florida, USA
2003
A. One nice thing about a public forum is if my guess is poorly founded someone will usually correct me. I doubt that the chloride ion itself is a problem, if the solution was rinsed, because galvanized finishes are widely used for saltwater exposure (anchors, boat trailers, etc.). However, to keep the chlorine in solution, bleaches have a fairly high caustic content--and zinc dissolves in alkali as well as in acid.
I think if the homeowners diluted the bleach substantially, which I would expect based on the economics of spraying a house, and then rinsed it, than it would have no impact. But if they sprayed full-strength bleach (which is quite difficult to rinse) there might be a problem.
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Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003
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