This study focuses on evaluating the safety conditions for workers involved in maintaining and repairing shipping containers. This study begins by identifying and confirming the risk factors that affect safety in container maintenance and repair (CMR) services. Next, it introduces a continuous risk matrix model to assess those factors. To put the model to the test, a field survey was conducted across CMR service operations in southern Vietnam. The proposed continuous risk matrix offers valuable insights for developing theoretical approaches in risk assessment research. Meanwhile, the empirical findings may provide practical information for the managers of CMR services and the government’s labor department to make policies to enhance work safety efficiency.