A WEB DECISION SUPPORT SYSTEM FOR GAS PIPELINE RISK ASSESSMENT

The assessment of the risk is a key factor in every Pipeline Integrity Management System (PIMS). In order to maintain gas pipeline integrity we must understand the risk factor. This includes the analysis of the probability of failure and the potential consequences. There are two approaches to estimate the risk: quantitative and qualitative. The quantitative methods involve historical failures date base or computer simulation. The qualitative methods are based on the expert's opinions and can gather the local experiences of the pipeline operator. In this paper the model based on the qualitative risk indexing method is presented. Two groups of gas pipelines and surroundings parameters are considered. In the first group are parameters which have the influence on the probability of failure. The second group is constituted from the parameters which have influence on the potential consequences. Having the list of these parameters the relative importance of each parameter is discussed among the group of experts. Once the consensus is reached, the model of pipeline failure risk estimation is created. In the next step the risk categories criteria are formulated. The risk criteria for five risk categories were formulated. The model and the risk categories were implemented in the Web based decision support system. The pilot tests of the system were performed and the results are presented.