Abstract: In order to carry out the‘12th Five-Year’development program of petrochemical and chemical industry and cancel hidden dangers in inorganic salt industry at first，safety risk assessment will be conducted for the enterprises，which engaging in the business of dangerous chemicals，according to requirements of Safety Standardization for Enterprises of Hazardous Chemicals as well as stipulations of related departments，in the next several years.HAZOP （Hazard and Operability Study） is the most advanced and vehemently recommended method by government departments for doing this work.Basic process of HAZOP was introduced and the necessity and effectiveness of using HAZOP to evaluate in-service inorganic salt plants were also described by giving an accident case in a hydrogen peroxide production.

Key words: in-service inorganic salt plants；standardization of safety；HAZOP；deviation, guide word