I've been deaf on one side for over 15 years because of a tumor. By definition I can't damage my hearing on that side. Mechanically everything through the middle ear still works but the inner ear pretty much died.
Out of idle curiosity, I did some shooting without protection on my deaf side while being sure the good side was well taken care of.
The sound/pressure wave was strong enough to cause some real discomfort in my ear. I could get a real sense of the damage that could be caused that is overlooked because folks notice how their hearing is immediately affected and miss the underlying cause. The underlying was all I had.
So, if someone who is (half) deaf won't go without protection what excuses do the hearing have?
"What kind of man would put a known criminal in charge of a major branch of government? Apart from, say, the average voter." - Terry Pratchett