GIS-based simulation of emergency management for leak of gaseous / volatile toxic substance

With the acceleration of China´s urbanization, the issue of city´s public security has aroused widely concern in society. How to deal with the Emergency of toxic gases contamination appropriately in the densely populated area thus reducing the risk of public safety is quite an important problem. Taking Beijing as the study area, based on the technology of Geospatial Database, this paper takes Gaussian diffusion model as analytical mode which is guided by statistical theory of turbulence and simulates the process of noxious substance spread in various scenarios (producing a raster result) by GIS used to display and analyze. Then we analyze the different grades of hazard probability so as to control risk and achieve safety planning. The result agrees well with the actual situation, which give a more scientific guidance to emergency management and personal emergency. The study also provides scientific bases for formulating emergency and prevention planning raise government´s capability to respond to emergency.