Safety Effectiveness of Integrated Accident Prevention Strategies

There are potential interactions among approaches to reduce or prevent certain accident causes. Given the overlapped safety benefits of various measures for accident prevention, it is necessary to identify their interactions and quantify the safety effectiveness of combined accident prevention strategies. This study focuses on strategies to prevent broken rails and broken wheels, respectively. Improved wheel condition reduces the impact load on the rail, thereby may reduce broken-rail-caused derailments. In this paper, we propose a quantitative framework to assess the safety effectiveness of combined accident prevention strategies under various operational conditions. In the larger context of railroad hazardous materials risk management, integrated accident prevention can be compared to other means of risk reduction measures, such as tank car safety design enhancement or operational changes. INTRODUCTION Train accidents cause damage to infrastructure and rolling stock, disrupt service, and may cause casualties and harm the environment. Therefore, accident prevention is of great importance for the rail industry and government. An accurate assessment of the cost-effectiveness of accident prevention measures, individually or in combination, enables optimal allocation of resources for safety improvement. When multiple accident prevention strategies are applied, their safety benefits may overlap. For example, reducing wheel defects may not only prevent broken-wheel-caused derailments, but also reduce the likelihood of broken rails due to reduced impact load at the wheel-rail interface. A more detailed illustration of the interaction between track-related and rolling stock-related defects is presented in Fig.1. The interaction between accident causes makes it more complex to estimate the safety effectiveness of combined accident prevention strategies. The focus of this paper is to evaluate the safety benefits of a combination of broken rail prevention and broken wheel prevention.