Can dogs wear foam ear plugs sold for humans?

My new dog barks at the telephone, microwave, toaster oven - anything that beeps. We are working on training him out of this but we have to travel by plane with him soon. He will travel in-cabin, under the seat, and we are worried about him barking at sounds like the stewardess bell. Can we use those foam ear plugs intended for humans - the kind you squish then insert in the ear c? Is plugging his ears a concern re ears popping because of the pressure with the plane ascending and descending?