Chemical accidents in the vicinity of densely populated areas can cause colossal damage. Close proximity of chemical facilities to the general public has been identified as a major issue for increased human exposure in 43% of the accidents investigated by the U.S. Chemical Safety Board (CSB). This emphasises the need for incorporating societal factors in risk assessment to plan actions in order to minimise exposure during accidents. The purpose of this research is to develop a model for the assessment of human vulnerability and risk due to chemical accidents. A GIS based methodology is proposed which uses computer aided hazard modelling tools and technical guidelines to model accidents and assesses population vulnerability. The population vulnerability is determined based on a set of societal indicators derived from relevant research work, expert opinions and suggestions by World Bank. Risk is defined as the probable magnitude of harm to humans and dependent on both the degrees of hazard and vulnerability. A case study is carried out by applying the methodology to Meghnaghat Industrial Area in Bangladesh. Accident scenarios are built and hazard modelling software ALOHA is used to spatially display accident footprints. Vulnerability of population is assessed using data from Bangladesh Bureau of Statistics (BBS) and field survey. The hazard footprints and vulnerability map are superimposed using mapping software ArcGIS to generate a composite risk map. The risk map is used to assess existing land use and recommendations are made for future land use planning. The composite risk map is expected to be of help for effective community response, emergency response planning and allocation of medical and support services during emergencies.

人口稠密地区附近的化学事故可能会造成巨大的破坏。在美国化学安全委员会（CSB）调查的43％的事故中，化学设施与公众之间的紧密接触已被视为增加人体暴露的一个主要问题。这强调了在风险评估中纳入社会因素以计划行动的必要性，以最大程度地减少事故期间的暴露。这项研究的目的是建立一个模型来评估化学事故对人类的脆弱性和风险。提出了一种基于GIS的方法，该方法使用计算机辅助危害建模工具和技术指导来对事故进行建模并评估人口脆弱性。人口脆弱性是根据相关研究工作中得出的一系列社会指标确定的，世界银行的专家意见和建议。风险定义为可能对人类造成伤害的程度，并取决于危害程度和脆弱性。通过将该方法应用于孟加拉国的Meghnaghat工业区进行了案例研究。建立事故场景，并使用危害建模软件ALOHA在空间上显示事故足迹。使用孟加拉国统计局（BBS）的数据和现场调查评估了人口的脆弱性。使用地图绘制软件ArcGIS叠加危险足迹和脆弱性图，以生成综合风险图。风险图用于评估现有土地使用情况，并为将来的土地使用计划提出建议。综合风险图有望帮助社区做出有效反应，