Аннотация: The key indicators characterizing main pipeline safe operation are presented. The author has concluded that the key indicators, characterizing main pipeline safe operation include: linear section damage at the main gas pipeline (MGP) caused by the crack-like defects, including stress - corrosion cracks; MGP linear section damage caused by ovalization of pipe section area; MGP linear section damage connected with such pipe defects as corrugation and dents; fitting damage at the MGP line section; welded joint operational reliability index; damage of the linear section at the main gas pipelines (LSMGP) due to the increased stress levels; LSMGP damage due to fluctuating loads.