I think it would depend more on how easy it is to open the coffin. If the lead lined coffin has well maintained hinges that allow it to open with little effort, that’s less acceptable than a wooden coffin that is nailed shut.
Corpse acceptability is inversely proportional to corpse accessibility.
Ah, so the corpse acceptability depends on the coefficient of corpse-permeability of the intermediate space as well as the distance.
Lead lined coffins are safer than wooden ones. This might also explain the thick metal doors you always see in morgues on tv.
I think it would depend more on how easy it is to open the coffin. If the lead lined coffin has well maintained hinges that allow it to open with little effort, that’s less acceptable than a wooden coffin that is nailed shut.
Corpse acceptability is inversely proportional to corpse accessibility.