The Oil Spill Hazard Index (OSHI) elaboration. An oil spill hazard assessment concerning Italian hydrocarbons maritime traffic

•We elaborated an index, called OSHI, for assessing Oil Spill Hazard.•We assessed OSHI indices for the whole Italian coastline.•We elaborated a GIS database for comparative spatial analysis of the OSHI.•Results may be helpful for developing an oil spill contingency plan.

The main purpose of this paper was to develop an Oil Spill Hazard Index (OSHI) concerning hydrocarbon maritime traffic. The subsequent aim is to evaluate this hazard index along the whole Italian coastline and waters.The OSHI processing derives from the aggregation of two hazard subindices: R1 (concerning hydrocarbons handled at ports) and R2 (related to hydrocarbons in transit). In order to assess the OSHI along the Italian coastline (8660 km), it has been divided into 335 coastal stretches and for each of them an OSHI value was calculated, considering the amount of crude oil and petroleum products moved in the Italian ports or just passed through continental shelf waters, as well as the major Mediterranean oil routes affecting the Italian seas.All the results (national oil traffic database and hazard indices) were recorded in a Geographic Information System (GIS) database that contains a comparative spatial analysis of these records in order to achieve a critical scale of the oil spill hazard along the Italian waters and coasts.The obtained results include computerized cartography and operational maps representing useful tools for decision-makers as well as practical guidelines for the elaboration of a national oil spill contingency plan, and the application of the principles of Integrated Coastal Zone Management (ICZM) by public administrations and local stakeholders.