I am designing an exhaust system for a small room (~400SF) containing a closed, dilute sulfuric acid system. Airflow is approx. 6 ACH. Is galvanized (w/high-performance paint) the cheapest option, or would a plastic duct be more chemically resistant?
When you do this, check where the exhaust ends up.
I had a very unpleasant time recently, changing out galvanised equipment pad covers, for stainless on the roof of a facility, because the acid fumes had rotted the galvanising off the covers, allowing them to rust and get holes.
B.E.