•A dynamic emergency route planning model for major chemical accidents was proposed.•The Dijkstra algorithm is modified to solve the multi-objective optimization problem for the emergency route selection.•An individual emergency risk classification method for major chemical accidents was obtained. Combining scenario construction with the characteristics of individual emergency behavior is necessary for the emergency route planning of major chemical accidents. We investigated this challenging decision problem and constructed a multi-indicator emergency risk assessment method that considers the evacuation speed of different population types and health consequences caused by various risk components. We also designed a modified Dijkstra algorithm to solve this dynamic multi-objective route planning problem. The comparative experiment results demonstrated that the proposed algorithm performs relatively better than the traditional Dijkstra algorithm. Finally, we performed extensive case studies where our simulation results demonstrate that the proposed model provides reliable and practical emergency route planning services for various personnel types under different accident scenarios. Compared with the commonly used single-dimensional assessment method, this comprehensive and informative assessment of the emergency risks faced by the population in different regions could serve as a useful reference for the formulation and implementation of emergency plans in case of major chemical accidents.