More seriously, perhaps, the orlop deck was usually where the naval surgeon and his "mates" worked during battles on frigates and line of battle ships during the Napoleonic wars. It was convenient to the gundeck (where most of the casualties would occur), and was relatively protected, i.e. there were two wooden walls between the orlop and the incoming cannon shot.

I have never understood, and it has never been satisfactorily explained to me, why naval ships didn't have armour plating (iron sheeting) on the outside of the hull along the line of the gundeck. It would have saved hundreds, if not thousands, of sailors from maiming or death. And it wouldn't have been so heavy as to make the ship unmanageable (i.e. top heavy) in bad weather.

- Pfranz