Provide a quantitative risk assessment model for fire and explosion accidents in oil floating roof tanks

Abstract

Background and Purpose: In the oil industry, storage tanks are used to store chemicals such as hazardous and flammable hydrocarbons. Today, due to many reasons such as natural disasters, operational errors, etc., fire and explosions accidents have occurred in these tankers and are a serious threat to the lives of individuals and property and the environment. The purpose of this study was to provide a method for assessing the risk of fire and explosions accidents in external floating roof tanks. Materials and Methods: Initially, information related to fire and explosion of oil tankers to design the first questionnaire were collected Then, for more information about the causes of fire and explosion and the content validity of the questionnaire, we visited Tabriz Oil Refinery and Tabriz Oil Storage. Then, each of the final factors was weighed and prioritized with the Analytical Network Process (ANP) method with the help of the Super Decisions software. Finally, to assess the reliability of the questionnaire from the Cronbach's alpha test, To sufficient sample size from the KMO index, to identify the factor structure and check the factor loads from the EFA test and to ensure the proper selection and fit the final model from the CFA test was used. Finally, regression and covariance tests were used to modify the final model. Result: At first, as a result of library studies, 89 of the causes of fire and explosion of oil tankers were gathered. Then content validity was finalized according to the views of several process, safety and firefighters engineers, and by eliminating 7 factors, finally, the cases were classified in the form of 11 main criteria and 71 sub-criteria. Then, as a result of risk factors weighting, prioritizing the effective factors in the fire and explosion of the tankers was respectively natural disasters, static electricity, operating fault, fault system, fault maintenance, leakage of torn lines, equipment reliability, the internal consistency of all groups (α> 0.6) was confirmed. Based on the EFA test results, the data were divided into 11 classes; in the next step, the CFA results confirmed the 11-factor model obtained from the efa based on fitness indicators(rmsea=0.048, x2/df=1.62, cfi =0.571, tli=0.578). Also, according to the results of specific factor load tests and regression, two sub-criteria “explosion-proof motor and equipment used” and “lack of coordination with urban firefighting equipment” were deleted. Finally, after correction and validation of the final model, 80 remaining causes were classified in the form of 11 main criteria and 69 sub-criteria. Conclusion: The purpose of this study was to provide a method for assessing the risk of fire and explosion accidents in oil floating roof tanks. Accordingly, the most important risk factors of fire and explosion tankers were collected and prioritized and finally presented in the form of valid questionnaire. This questionnaire can be used in most process industries with external floating roof tanks, including oil and gas refineries, to identify and assess the risk factors of fire and explosion or to prioritize control measures to prevent and reduce fire accidents.