Railroad transportation of dangerous goods: Population exposure to airborne toxins

Hazardous materials are potentially harmful to people and environment due to their toxic ingredients. Although a significant portion of dangerous goods transportation is via railroads, prevailing studies on dangerous goods transport focus on highway shipments. We present an analytical framework that incorporates the differentiating features of trains, notably volume and nature of cargo, in the assessment of transport risk. We focus on hazardous materials that are airborne upon an accidental release into the environment. Each railcar is a potential source of release, and hence risk assessment of trains requires representation of multiple release sources in the model. We propose a risk approximation approach, which is not only effective but also robust with regards to the positioning of hazardous cargo in the train. We report on the use of the proposed approach for the assessment of population exposure associated with “Ultra-train” that passes through the city of Montreal everyday.