The risk of loss of containment is a major concern within the petrochemical sector. Loss of containment accidents are often the result of some sort of breakdown between the human/technical interface, but may also be caused by malicious acts such as sabotage, extortion, physical terrorist attack (including insider collusion) and SCADA (IT systems) attack.
The Seveso chemical plant accident in Italy in 1976 prompted the EU to adopt legislation aimed at the prevention and control of major accidents involving chemical plants. The Seveso II Directive applies to some thousands of industrial establishments where dangerous substances are present in quantities exceeding the thresholds in the directive, but exclude such areas as transportation, ports and pipelines.
For more on this, go to the ARC Resources weblinks page at http://www.arc-tc.com/pages/resources_publications.asp. Chemical Plant Security, which provided hyperlinks to sites explaining Seveso II, can be found under the letter C.