With the rapid development of industry, the number of pipelines that are proposed or under construction is increasing year by year, connecting different regions of a country and, more and more, different countries. Thus, an accidental loss of containment from a pipeline involves a certain risk, which could imply potential consequences on people, equipment and environment. Therefore, the existence in some places of a large net of pipelines has a clear influence on land-use planning, especially in the ones with intense activities, which usually are the inhabited zones. In this paper, a historical analysis is performed on a sample of 1063 accidents that occurred in onshore pipelines, to illustrate the risk associated to these systems and its significance in land-use planning.Peer ReviewedPostprint (author's final draft

Parallel pipelines are frequently installed over long distances, due to the difficulty in creating or maintaining the required corridor. This implies that a release in one pipeline can seriously affect another one. The main risks associated with this domino effect are the erosive action of fluid-sand jets and the thermal action of jet fires. In this paper a survey has been performed on the accidents that have occurred, and the diverse possibilities and the associated domino sequences are analysed. The probability of occurrence of this domino effect is a function of the location of the hole, the direction of the jet, the solid angle that the jet is outlining, the diameter of both pipelines, and the distance between them. A mathematical model has been developed to estimate this probability. The model shows how the probability of domino effect decreases with the distance and diameter of the source pipe, and increases with the diameter of the target pipe. The frequency of the domino effect can be estimated from this probability and from the frequency of the initiating pipe failure plus, in the case of jet fire impingement, the probability of ignition. The frequency of the secondary pipe failure thus calculated, always higher than the individual frequency of this pipe, allows obtaining more realistic risk analysis results. HIGHLIGHTS In parallel pipelines domino effect can have a significant influence.  Domino effect will be originated by jet erosion or jet fire impingement.  The domino effect probability depends on the geometric arrangement of the system.  A mathematical model has been developed to estimate domino effect probability.  This probability allows a more realistic estimation of failure frequencies. ABSTRACTParallel pipelines are frequently installed over long distances, due to the difficulty in creating or maintaining the required corridor. This implies that a release in one pipeline can seriously affect another one. The main risks associated with this domino effect are erosion by fluid-sand jets and the thermal action of jet fires. In this paper a survey has been performed on the accidents that have occurred, and the diverse associated domino sequences are analyzed. The probability of occurrence of domino effect is a function of the location of the hole, the jet direction and solid angle, the diameter of both pipelines and the distance between them. A mathematical model has been developed to estimate this probability. The model shows how the probability of domino effect decreases with the distance and diameter of the source pipe, and increases with the diameter of the target pipe. Its frequency can be estimated from this probability and from the frequency of the initiating pipe failure plus, in the case of jet fire impingement, the probability of ignition. The frequency of the target pipe failure thus calculated, always higher than its individual frequency, allows a more realistic risk analysis.

Pipelines are commonly considered a safe alternative for the transportation of hazardous materials. However, in case of failure, pipelines still pose major risks to the environment and to the population potentially exposed. The aim of the present work is to provide occurrence probabilities of the intermediate and final events following the accidental release of hazardous materials from pipelines. A collection of incidents and accidents occurred worldwide in connection with the use of onshore long-distance pipeline networks, has been gathered to make up a specific database for the analysis of incidents in pipelines. A qualitative and quantitative analysis of the data has allowed to develop detailed event trees for the different classes of hazardous materials, and to calculate the probability of occurrence of the final outcomes. The investigation has also aimed at identifying, for each type of release, the relationship between the final events and the causes of the pipeline failure. The results obtained represent a useful and needed starting point in Quantitative Risk Analysis of hazardous materials transportation via pipelines.Peer ReviewedPostprint (author's final draft

A model to predict crater dimensions given a LOC in underground pipelines is proposed • The model implements 57 real accidents of natural gas underground pipelines • The approach proposes worst, mean and less severe scenarios to support decision-making • Some applications in Domino effect scenarios and Right-of-Way distances were discussed

The formation of a crater by the abrupt and catastrophic rupture of a high-pressure pipeline can be highly relevant, especially when the crater uncovers other pipelines, which could undergo a domino effect with a significant increase of the consequences on people or on the environment. However, this scenario has been only partially studied in the literature. To assess the influence of the pipeline parameters on the dimensions of the resulting crater, a statistical analysis of accidental ruptures of buried natural gas pipelines that have involved the formation of a crater was carried out. Mathematical expressions are proposed to describe the proportionality relationships found, which can be very useful to support adequate separation distances in the design and construction of parallel corridors of pipelines after appropriate escalating effects are considered. Finally, detailed event trees were developed to calculate the probability of occurrence of the final outcomes, as well as the identified domino sequences, based on a qualitative and quantitative analysis of the data. The study of these accident scenarios, based on actual cases, represents a useful and needed advance in risk analysis of natural gas transportation through pipelines.