The first thing is clams and crab are separate items in the regs. I sometimes lump them in my head regarding the regs for some reason. I guess because ‘shell’?
The next is ‘from the beach’ also includes docks and anything not in a boat.
Follow the closures on the maps to be safe. Some of the biotoxins have no cure, so up to you if you want to take a chance. It concentrates by the shore, but even if the coast is closed the bays are ‘usually’ still open.
Also, different than crab and clams, sand shrimp (ghost shrimp), because they process food differently, can be taken off the beach and eaten even when the beach is closed. They still don’t recommend eating the yellow fat though.
I like mussels, and find them beached on ocean debris often, but still won’t eat them if there is a closure. I have enough beat up body issues without possibly adding more, but everyone can decide for themselves if it is worth taking a chance.