In the Netherlands risk calculations are used for land-use planning around potential dangerous establishments and transport routes. The Dutch government propagates the importance of identifying risks by means of a uniform method of calculation in order to improve the robustness and comparability of risk analyses.
For transmission pipelines two new uniform methodologies have been developed and are mandatory since January 2011. The role and the responsibilities of both pipeline operators and competent authorities are regulated by law. This legislation applies to transmission pipelines transporting natural gas and oil products. Regulations for pipelines transporting chemicals are to be included once the corresponding risk calculation methodology has been adopted and the consequences on land-use planning have been identified.
This paper describes the risk methodology to be used in the Netherlands for trans-mission pipelines transporting chemicals with which the consequences for land-use planning can be calculated. The methodo¬logy for pipelines transporting chemicals has been developed in cooperation with the Dutch pipeline operators. In the Netherlands these pipelines have a total length of about 3000 kilometer and 20 different chemicals such as ethylene, hydrogen, chlorine and carbon dioxide are involved. The methodology comprises aspects such as failure frequencies, ignition probabilities and release direction. An example is given demonstrating the newly developed methodology.