A method of preventing misoperations in the process of producing light magnesium carbonate with a rotating packed bed (RPB) is proposed in this paper. The main problem in this process is that the carbonization reaction and the purity of light magnesium carbonate are easily affected by misoperations, which result in the waste of materials and energy, low quality of the product, and so on. A hazard and operability analysis method was used to analyze misoperations in the process of producing light magnesium carbonate. It was found that the situations caused by misoperations, such as the operation step neglect and inversion, can be detected and arranged properly by a misoperation hazard and operability (MO-HAZOP) analysis program according to the probability of the misoperation occurrence. Based on the analysis results, the measures in terms of full automatic mechanism, programmed control interlock mechanism can be adopted to reduce and prevent misoperations and to maintain the system, normal production. The use of this method in the production of light magnesium carbonate has shown that the occurrences of misoperations and accidents were reduced drastically, and the security and protection system in this process was improved considerably. (C) 2009 Elsevier Ltd. All rights reserved.