In the last thirty years lightning properties have been measured with a high degree of detail. Yet, the mechanisms by which lightning causes failure of buried structures are still not fully identified. This work addresses results from experimental studies and modeling of two lightning
failures in buried natural gas pipelines. In both cases leaks followed by fire were caused by small punctures as a consequence of localized fusion of the pipe wall metal.
Bolts hit the ground very close to the pipelines and produced the ionization of the soil in an area which was larger than their topsoil. Then,
failures were caused by Joule effect, due to large currents generated by the establishment of arcs between the pipeline and the point of impact.
Models to check the effect of the topsoil (burial) depth, the closeness of air-breaking metallic components and other construction characteristics on the probability of occurrence of these phenomena are reviewed. Ways to minimize the impact of this damage mechanism upon the integrity of buried pipelines are finally discussed.
