Abstract: In order to analyze the risk in the vicinity of the gas transmission pipeline, an individual risk calculation model is established. The model consists of two parts involving the calculation of pipeline failure frequency and the calculation of the hazardous consequences of failure. The model divides the causes of pipeline failure into six categories. The method of correcting the reference frequency is adopted to calculate the frequency of pipeline failure caused by each category of the failure causes. The calculation and analysis of hazardous consequences include four parts covering leakage rate calculation, calculation and analysis of ignition probability, fire calculation and analysis, and degree of injury. Jet fire is used to represent the hazardous consequences of pipeline leakage. Based on the calculation and analysis of the failure frequency and leakage consequences, the individual risk in the vicinity of the pipeline is calculated. Thus, whether the risk in the vicinity of pipeline is acceptable or not can be determined. Examples of risk calculation show that rupture is the main factor for risk, and it is recommended that the control of rupture-inducing factors should be strengthened.

Key words: individual risk, failure frequency, gas pipeline, jet fire