Regional Environmental Risk Assessment Under The Scenarios Of Domino Accidents

Domino effect is responsible for several catastrophic accidents that took place in the chemical production process. Although the destructive potential of these accidental scenarios is widely recognized, limited attention was paid to this subject in the research and in the supervision and management of environmental risk in China.Based on international research achievements in domino effect, this article introduced the definition of domino effect, pointed out its accident types and mechanism. Furthermore, Domino effect was incorporated into environmental risk assessment of chemical industrial parks, and the identification of domino accidents was discussed, the frequencies of domino accidents were calculated with escalation probability models and Monte Carlo simulation, the consequences of contamination accidents were simulated with atmospheric and water diffusion models, the regional environmental risk under domino accidents scenarios was further analyzed in geographic information system, and the precautionary measures of domino environmental risk was put forward. The case study of Nanjing Chemical Industrial Park showed that 67.5% risk sources would spark secondary accidents and each primary accident could spark 9.58 secondary accidents on average. The probabilities of accidents under secondary scenarios and third scenarios were 3.72 times and 7.09 times more than primary accident scenarios respectively. The regional environmental risk under secondary accident scenarios and third accident scenarios were 6.40 times and 12.33 times of the primary accident scenarios respectively. It is verified that the domino effect could expand regional risks obviously and should be controlled as the main risk factor.Compared with the traditional environmental risk assessment, this method can predict the secondary accidents, and calculate the probability and the consequence of these accidents. Thereby, the corresponding preventive measures can be taken so as to reduce the probability of domino accidents and enhance the reliability and practicability of risk assessment.