Safety emergency refers to the sudden occurrence of natural disasters or social events caused by force majeure and human factors, which may or will cause serious casualties and property losses, damage the ecological environment and endanger social and public security. In case of emergency, various emergency plans shall be formulated and various emergency measures shall be taken to minimize the loss caused by the accident. Generally, it includes various natural disasters, accident disasters, public health events and social security events. The emergency has the basic characteristics of severity, uncertainty and consequence emergency. Although the occurrence of emergencies, people can not stop it, but people can take measures to collect as much information as possible, understand the regularity of emergencies and prevent the occurrence of emergencies.