Scenario Analysis of the Risk of Gas Pipeline Failures in the North

Abstract

Low temperatures and abnormal meteoconditions of the North have significant effect both on the accident frequency, and on accident development. Abnormal weather conditions of the North are characterized by the powerful temperature inversions arising at an anti-cyclone due to the emission of permafrost soil at extremely low temperatures of air and conditions of air stagnation. These abnormal conditions influence process of gas dispersion in the atmosphere, promoting its deceleration and formation of explosive concentration of gas at the Earth’s surface. Based on the results of gas pipeline failures analysis occurred in the North, the main causes of gas pipeline accidents were identified, the gas leakage “fault tree” from the gas pipeline was developed with estimation of failures frequencies, and the frequency of emergency situations in case of gas leakage from the gas pipeline was estimated. The most dangerous scenarios of gas pipeline accident evolution have been identified and their risk levels in the zone of the damage factors have been assessed on the basis of acceptable risk criteria. It is justified to increase the action range of damage factors in an explosion of methane -air mixture cloud in open space at presence of temperature inversion.