The "Guidelines for Investigating and Controlling Safety Risks in Chemical Parks" stipulates that chemical parks should conduct overall safety risk assessments of chemical parks at least every three years, propose countermeasures and measures to eliminate, reduce, and control safety risks and implement them effectively. If the "four to" scope of the chemical park, or the large change in the number of major hazardous sources may lead to a significant increase in the overall safety risk of the chemical park, or the increase in the safety risk level requires management according to the high (A) or higher (B) risk level, or if a large or above occurs or causes major social impacts, an overall safety risk assessment should be carried out again.