Publication Detail
Assessing Truck Accident Probabilities and Their Implications for the Transport of Nuclear Assemblies
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UCD-ITS-RP-93-01 Presentation Series |
Suggested Citation:
Jovanis, Paul P. (1993) Assessing Truck Accident Probabilities and Their Implications for the Transport of Nuclear Assemblies. Institute of Transportation Studies, University of California, Davis, Presentation Series UCD-ITS-RP-93-01
Probabilistic Safety Assessment '93: American Nuclear Society, Clearwater, FL
There is a need to assess the risk posed by the movement of nuclear weapons components and secondaries by truck. An important part of such a probabilistic risk assessment (PRA) is the estimation of the probability of a particular type of accident, given movement of the package by a safe secure transport (i.e. SST). Because of the nature of the cargo carried, the emphasis is on accident characteristics and outcomes: What was the ov for the crash? Did the trailer overturn? Was there a fire as part of the accident event?
Transportation accidents differ fundamentally from many industrial accidents because the concept of an "event" as a failure of a system or component is not applicable. As an alternative, it is more accurate to consider a set of factors which contribute to an increase or decrease in accident likelihood. Some factors, such as vehicle type, are constant throughout the shipment. Others, such as road geometry, will vary non-systematically throughout the trip; still others, such as driver alertness, may vary much more systematically. A probabilistic risk assessment requires a model of these trucking operation attributes, a network of alternative routes, and a data set that can be used to estimate accident probabilities.
The network of alternative routes for shipments of this type is characterized by a relatively limited set of origins and destinations with highway links connecting them. Given substantial safeguard concerns, even the number of candidate highway links is likely to be limited.
This paper, therefore, does not focus on the network, but discusses the development of the model of trucking company operations and the data set used to estimate accident probabilities. As the discussion evolves, the relevant roadway attributes will be described.
There is a need to assess the risk posed by the movement of nuclear weapons components and secondaries by truck. An important part of such a probabilistic risk assessment (PRA) is the estimation of the probability of a particular type of accident, given movement of the package by a safe secure transport (i.e. SST). Because of the nature of the cargo carried, the emphasis is on accident characteristics and outcomes: What was the ov for the crash? Did the trailer overturn? Was there a fire as part of the accident event?
Transportation accidents differ fundamentally from many industrial accidents because the concept of an "event" as a failure of a system or component is not applicable. As an alternative, it is more accurate to consider a set of factors which contribute to an increase or decrease in accident likelihood. Some factors, such as vehicle type, are constant throughout the shipment. Others, such as road geometry, will vary non-systematically throughout the trip; still others, such as driver alertness, may vary much more systematically. A probabilistic risk assessment requires a model of these trucking operation attributes, a network of alternative routes, and a data set that can be used to estimate accident probabilities.
The network of alternative routes for shipments of this type is characterized by a relatively limited set of origins and destinations with highway links connecting them. Given substantial safeguard concerns, even the number of candidate highway links is likely to be limited.
This paper, therefore, does not focus on the network, but discusses the development of the model of trucking company operations and the data set used to estimate accident probabilities. As the discussion evolves, the relevant roadway attributes will be described.