Technical Reports

A Risk Assessment Study on the Transportation of Hazardous Materials over the U.S. Railroads

  • 01
  • Nov
  • 1988
AUTHOR: Federal Railroad Administration; Phani K. Raj
SUBJECT: Hazardous Materials, Safety Advisories
KEYWORDS: Hazmat, Train Accident, Risk casualty, Annual frequency, Safety, Probability, Release main line, Yard, Risk profile
ABSTRACT: A comprehensive and generic risk assessment model has been developed for evaluating the risk to the public from the transportation of hazardous materials (Hazmat) on rail over specified routes. The model considers the various operational and hazmat property parameters. These include the make-up of the freight trains, annual volumes of transport of particular Hazmat, train accident statsitcs both on main line and in yards, effect of leak prevention devices such as head shields and shelf couplers, population denstiy distribution and the behavior of the chemicals in the environment after release. The model developed was utilized to evaluate the risks posed in transporting LPG chlorine and sulfuric acid on two (alternative) routes between the same origin-destination pair. Historical main line and yard accident data together wtih the current volumes of transportation of the specified Hazmats were considered. The results are presented in the form of risk profiles. These results indicate higher risk from chlorine on both routes compared with that due to LPG or sulfuric acid. The sulfuric acid risk is in order of magnitude, smaller than either the LPG or chlorine risk. Safety measures, such as head shields and casualties but seem ot have less impact on the low casulaty end of the risk profile. A similar positive effect in risk reduction is seen from emergency response action following an accident. Sensitivity of the risk profiles to various other parameters were also investigated.