NaTech risk in production plants in regions subjected to high seismicity, tornado or flooding hazard

Seismic phenomena and tornadoes are among the most relevant causes of damage on the built environment and their effect on industrial plants might not be limited to mere structural damage. Under particular conditions, such as the presence of inflammable substances (hydrocarbons or other chemical products), earthquakes, flooding and tornadoes can trigger fires and the damages on a plant can cause the release of hazardous materials. Such scenarios are named as NaTech because of the combination of natural/technological hazards. Due to the technological aspects involved in such risk, the related costs are high in terms of damages to the environment and remediation activities on the damaged items. Chemical plants usually consist of tall industrial items (reactors, distillation columns, etc...) or large tanks, such as structures that are largely affected by seismic effects (in terms of large displacement and sloshing).

For this reason, NaTech hazards have already been considered in the industrial risk analyses for production plants in developed countries, say in the US and Europe (Italy, Greece), where the seismic or meteorological hazard is high. Despite the strict regulations concerning seismic safety, fire prevention and restrictions for hazardous substances, many criticalities have already been highlighted. Considering NaTech hazards in a disaster risk reduction framework is fundamental, in particular in fast-developing areas such as Iran, China, Brazil and African countries, where specific regulations in terms of industrial safety are not detailed, say absent, and no seismic-resisting rules are considered in the design of the plants. To tackle NaTech hazards, this report proposes a two-stage risk analysis: a risk assessment based on the technological hazards is first performed in order to identify the critical items, then the seismic vulnerability is computed through quick-assessment procedures. The outcomes of the research can be useful for helping the countries in which NaTech risk cannot be avoided.

This paper is a contribution to the 2019 edition of the Global Assessment Report on Disaster Risk Reduction (GAR 2019).

To cite this paper: 

Chiaia, B.; De Biagi, V. NaTech risk in production plants in regions subjected to high seismicity, tornado or flooding hazard. Contributing Paper to GAR 2019