Assessing risk of metro microenvironmental health vulnerability from the coupling perspective: A case of Nanjing, China

Metro, as a convenient transportation, has many potential environmental risks during operation that pose a great threat to users, resulting in metro microenvironmental health vulnerability (MMHV). While prior research has focused on metro construction and safety management, some investigations have also addressed isolated metro microenvironment factors, such as air quality and noise, ignoring the underlying causes of health risks. Therefore, this research aims to reveal driving factors contributing to MMHV and assess the risk of MMHV from the coupling perspective. 14 Driving factors related to personnel, facility, environment, and management were firstly identified, along with their coupling relationships. Then, a risk coupling simulation model of the identified driving factors has been devised, which integrates a cloud theory-based coupling degree model framework and system dynamics principles to represent the interconnected risks posed by these factors. Finally, the constructed model is applied practically to discern the developmental trajectory of coupled risks emanating from the driving factors influencing MMHV. And the key factors at different periods were determined by adjusting coupling coefficients, so as to propose targeted strategies. Findings in this research offer valuable guidance for the implementation of diversified and precisely tailored measures to address MMHV at various stages of metro operation. This, in turn, contributes to the mitigation of health risks and ensures the sustained and healthy operation and management of metro.