New Flemish Approach for Risk Analysis System for the Transport of Dangerous Goods

Abstract

The safety of transport of dangerous goods is internationally regulated by ADR, RID, ADNR, etc. However, the risk of major accidents during the transport of dangerous goods on its surroundings is so far not adequately regulated, neither internationally nor in Flanders or Belgium. The Flemish government has developed a risk analysis system for the transport of dangerous goods. The system covers external safety of people for the transport modalities roads, railways, inland waterways and pipelines. It has to be seen as the technical tool for a Flemish safety policy to obtain the external risk of new developments of transport routes at an acceptable level, to detect and remediate existing bottlenecks over time and to clearly communicate about transport risks with the other involved authorities and the citizens. The risk analysis system is based on an approach of two steps. The first step consists of the determination of the general risk of a transport route, the second is a more profound calculation of a local risk at certain specific parts of the transport route. For the first step a general probability of an accident with loss of containment is calculated from statistical data resulting from reports of accidents in neighbouring countries or from international reports. The first step has to be done mainly because of lack of statistical data in Flanders. In a second step a fine tuning is done by determining a local probability of an accident. This local probability is based on accident data and on expert parameters (infrastructure and traffic parameters) for a specific part of the transport route. For each transport modality expert parameters are listed. The calculation of the effects and consequences is the same for the two steps in the risk analysis system. To indicate the consequences of a possible accident with dangerous substances, the number of people within the 1% lethality distance is determined. This is done for the different transport modalities and for four classes of dangerous goods (flammable liquids and gases and toxic liquids and gases) based on representative substances. The results are presented on geographical maps. For each transport route maps of probabilities, consequences and risks give a visual representation. With the risk analysis system comparisons can be done for different routes of the same transport modality to look for the most save route. The method allows also to compare different transport modalities for transporting dangerous goods between two points. The risk analysis system can support decision making as well as for the construction of new routes as for improvements of existing routes. The system is also to be seen as a tool to take into account safety matters in the policy of land use planning. The risk analysis system is applicable in other countries.