TRYING TO CLEAN DRIED AND HARDENED MUCK FROM THE TOP FLAT SURFACE OF THE STANDARD BETWEEN THE ENDS OF A RETURN IDLER WITH A BRUSH ON A FIVE FOOT HANDLE. HIS RIGHT HAND WAS PULLED INTO OR THRU THE BOTTOM ROLLER AND HE BECAME CAUGHT IN IT. HEJERKED HIS HAND OUT AND SUSTAINED AN AMPUTATION OF THE LAST JOINT OF THE RIGHT INDEX FINGER. INJURED IS LEFT HANDED.