4th CCPS Global Summit on Process Safety Okayama, Japan
Japan is a country with a high population density and land constraints. Thus, it is not uncommon to find hazardous installation in proximity to residential and commercial developments. Any major accident in these installations could have the potential for causing a large number of injuries and fatalities. In the case of industrial zones where hazardous installations are closely spaced, an accident in one plant may impact others leading to an escalation of the accident. Quantitative Risk Assessment (QRA) techniques are widely adopted to assess and evaluate whether such risks are tolerable.
In the context of land use planning, especially in places where scarcity of land is an issue such as Hong Kong and Singapore, QRA techniques are applied by the regulators to manage the development of hazardous installations whose impacts on the external population or industries could be a concern.
The industries in Japan emphasize on prevention of accidents by adopting, for example, safer design practices and inherently safe designs, while QRA is not commonly carried out in Japan. With the objective of evaluating the risk levels associated with the industrial areas in Japan, a QRA is performed for a hypothetical cluster of hazardous installations in a typical industrial zone environment. The case study also shows how a QRA can be useful in setting a uniform standard of safety for different types of hazardous installations; developing and prioritizing risk reduction measures; and preparing emergency plans. In addition, the practicality of implementing quantitative risk criteria for facility siting in Japan is also discussed in this paper, with a view to safely utilizing the land around hazardous installations.