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In May 2012 a seismic sequence occurred in Northern Italy that was characterized by two main shocks with a magnitude range between 5.5 and 6. These shocks represent a good case study by which to quantify the monetary losses caused by a moderate earthquake in a densely populated and economically well-developed area. The loss estimation accounts for damage to residential buildings, and considers the full effect of all the seismic aftershock events that lasted for nearly a month. The building damage estimation is based on the European Macroseismic Scale (EMS-98) definitions, which depict the effects of an earthquake on built-up areas in terms of observed intensities. Input data sources are the residential building census provided by Istituto Nazionale di Statistica-the Italian National Institute of Statistics (ISTAT)-and the official market value of real estate assets, obtained from the Osservatorio del Mercato Immobiliare-the Real Estate Market Observatory (OMI). These data make it possible to quantify the economic losses due to earthquakes, an economic indicator updated yearly. The proposed multidisciplinary method takes advantage of seismic, engineering, and economic data sets, and is able to provide a reasonable after the event losses scenario. Data are not gathered for each single building and the intensity values are not a simple hazard indicator, but, notwithstanding its coarseness, this method ensures both robust and reproducible results. As the local property value is available throughout the Italian territory, the present loss assessment can be effortlessly repeated for any area, and may be quickly reproduced in case of future events, or used for predictive economic estimations.

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One of the main objectives of the ITACA (ITalian ACcelerometric Archive) strong motion database, promoted by the Italian Department of Civil Protection, was to improve the characterization of the recording sites from a geological and geophysical point of view and to provide their seismic classification according to the seismic norms pertinent to Italy, namely the Eurocode 8 and the National Technical Norms for Constructions. A standard format to summarize the available information for the recording stations was first produced, in terms of a technical report dynamically linked to the database, i.e., some of the relevant information is automatically updated when the corresponding fields of the database are modified. Then, an important activity of collection, qualification and synthesis of available data was carried out, especially for stations that recorded the strongest earthquakes in Italy in the last 40 years, and for which a relevant number of studies have been published. In spite of this activity, among the more than 700 strong motion stations present in the ITACA database, only a limited number of them could be characterized by quantitative information on subsurface soil properties. For this reason, a dual seismic site classification criterion was implemented, either based on the standard V s,30 scheme, or, in the absence of such information, based on an expert opinion supported by shallow geology maps, mostly at 1:100,000 scale, and when available on the H/V ratios calculated on recordings. Owing 123 1780 Bull Earthquake Eng (2011Eng ( ) 9:1779Eng ( -1796 to the relevance in the Italian geographic and morphological context, a special care was also given to the topographic classification of stations, based on suitable criteria developed within a GIS environment.