Chemical accidents have occurred frequently in recent years, and most have occurred in small and medium-sized enterprises (SMEs). SMEs in the chemical industry face greater challenges than large enterprises with regard to accident prevention. However, SMEs have been unable to effectively learn from accidents due to the limited resources. The accident causation model is an effective tool to help the analyst learn from accidents. As a systematic accident causation model, the causes classification in the human factors analysis and classification system (HFACS) can match the characteristics of SMEs, but the cause of chemical accidents can be ineffectively identified by HFACS. In this study, HFACS was revised for the SMEs in the chemical industry, mainly consisting of three parts. First, based on the definition of factors in the original HFACS, the extended HFACS framework was obtained, which include 78 manifestations with the characteristics of the chemical accidents. Second, 101 accidents occurring in a SME in the chemical industry from 2012 to 2016 were analyzed though the extended HFACS framework. Finally, a new model, known as the HFACS-CSMEs, was obtained by further revising the manifestations and causes classification according to the statistical results of the accident analysis. HFACS-CSMEs consists of 15 cause factors and 56 manifestations, which can effectually identify and distinguish the causes in chemical accidents. Moreover, the easy-to-understand and statistically acceptable features of HFACS-CSMEs can cater to the SMEs regarding accident analysis. HFACS-CSMEs solves the problem that HFACS cannot be directly applied to chemical accidents and provides new ideas about preventing accidents in SMEs in the chemical industry.

近年来，化学事故经常发生，大多数发生在中小企业（SME）中。与大企业相比，化学工业中的中小企业在事故预防方面面临更大的挑战。但是，由于资源有限，中小企业无法从事故中有效学习。事故因果模型是帮助分析人员从事故中学习的有效工具。作为一种系统的事故原因模型，人为因素分析和分类系统（HFACS）中的原因分类可以匹配中小企业的特征，但是HFACS不能有效地识别化学事故的原因。在这项研究中，针对化工行业的中小企业修订了HFACS，主要包括三个部分。首先，根据原始HFACS中因素的定义，获得了扩展的HFACS框架，其中包括具有化学事故特征的78种表现。其次，通过扩展的HFACS框架，分析了2012年至2016年化工行业中的中小企业发生的101起事故。最后，通过根据事故分析的统计结果进一步修改表现形式和原因分类，获得了一种称为HFACS-CSME的新模型。HFACS-CSMEs由15种原因和56种表现组成，可以有效地识别和区分化学事故的原因。此外，HFACS-CSME的易于理解且在统计上可接受的功能可以满足SME在事故分析方面的需求。