One of major risks from plant operation involving with high hazardous chemicals are fire, explosion, and leaks that can become hazardous to communities, environment, and supply chain, disrupting business and production. Process Safety Management (PSM) is implemented to prevent major incidents from unwanted release of high hazardous chemicals. In Thailand, PSM regulations under the Industrial authority of Thailand, are applied to manufacturing process involving with possession, or transportation of any chemicals. An effective PSM program requires a systematic approach to understanding, evaluating and controlling the chemicals process from design, to operation, and maintenance stages.