Rabbinic prohibition further limits the Kohen of coming within four amoth6 feet 3.58 inches (based on rabbi Avraham Chaim Naehs definition of the amah) of an outdoor (i.e. no roof or overhang present) corpse or grave, but a fence or groove with a height or depth of 10 tefachim2 feet 8.27 inches (based on rabbi Avraham Chaim Naeh's definition of the tefach) eases the restriction and enables the Kohen to be within four tefachim of the corpse or grave.Shulchan Aruch, Yoreh De'ah chap. 371:5. Tur Yoreh Deah chap. 371
