According to the above analysis, the process to determine the improper degree of facility damage risk/ human injury risk is as below:
(1) Evaluate the importance for every facility according to the personnel density and economy density, and attach a ranking number for every facility;
(2) Calculate the damage risk(individual risk) for every facility, and attach a ranking number Ni for every facility;
(3) Bring the i and Ni that calculated by step (1) and step (2) into the equation (4) to get the improper degree of facility damage risk/ human injury risk.