I wouldn't hesitate for a minute to take one of my user Busses into a maritime environment particularly if I had available to me even the most rudimentary means of flushing and lubing the blade at the end of the day. If you're contemplating a purchase knowing beforehand it will be subjected to this kind of use, a coated blade would likely make good sense. Alternatively, if you're particularly concerned about extremely corrosive conditions, you can always pick yourself up a nice BetaTi fixed blade from Mission Knives. Of course, blade performance will suffer somewhat, particularly with the larger blades, but you can store a BetaTi blade in a bucket of salt water with no ill effects if you wish. IIRC, talonite and stellite are also pretty much impervious to salt water, but it seems to be getting more difficult to find fixed blades made out of these materials.