Comments by "Frank DeMaris" (@kemarisite) on "Naval Guns (1650 to 1820) - Stop blowing holes in my ship!" video.

@b b about 100%. Any sufficiently loud noise will do some damage, and cannon are well over that threshold. Someone who only gets occasional practice and no battles may not really notice the damage except for some tinnitus (ringing in the ears) after firing practice, but if you spend your career on a gun crew in an active navy, then you can count on being noticeably hard of hearing by the time you retire. Speaking as someone who is hard of hearing (for other reasons) and had reason to do some research.
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