After Hurricane Katrina, I got involved in a lot of this sort of thing while working for a manufacturer. Insurance companies were looking for documented ways to limit their exposure to having to pay for replacing equipment. There were more resources available at the time when I made a list to give out to people, almost all of those documents are now lost to time. But there was one from NEMA that is still available.
https://www.nema.org/docs/default-s...elines-handling-water-damaged-elect-equip.pdf
Basically though, that just says that breakers should NOT be reused, panels and gear CAN but the manufacturers need to be involved in the decision. One reason is that water may have compromised the bus insulators and braces, allowing tracking across the contaminated surfaces and leading to flashovers (this document doesn’t go into that much detail, but that’s the reasoning). In my case our equipment was all power electronics (Soft Starters) so there was no reasonable recovery method. We had one customer replace the Soft Starters but keep the breakers and bypass contactors, they had an internal flashover inside of a breaker and the contactors all failed within 3 months of being energized.
Bottom line, I would not recommend reusing it. SCCR and arc flash ratings are always based on equipment being in original factory condition with proper maintenance to be valid. Yours now misses on both counts. So if something DOES go wrong and someone gets hurt, even a crappy lawyer can drive a lawsuit bus through that opening.
