Kuma-KunYea, as chaosmagnet said, you're better off with a fixed blade. If you can't do fixed for whatever reason, probably look for something spec'd for diving. I guess it would be possible to use the falcon, but it's not designed with that in mind.
Kuma-KunIf you're looking for a folding dive knife, look at the spyderco Salt series. Somthing fully serrated. They're made of a proprietary metal (not a steel, no carbon) that does not rust, period. Also rustproof fittings.
chaosmagnetAs mentioned, folders in general are a bad idea unless specifically made as such (Benchmade did one).
Concerning the Falcon: Ball bearings used in the pivot, so you'd need to either flush the heck out of the knife, give it a long soak in fresh water (S35VN is corrosive resistant, but not that much), or take apart and oil. Ti scales would be slippery - and a sub 3" knife all but useless when it's made to cinch up using the finger choil. So, a fixed blade of non-corrosive SS with a big, heavily textured G10 handle and an easy deploy sheath is what you want. I'm NAUI certified for 42 years.