The model estimates the vulnerability of Switzerland's more than 2 million residential, commercial and industrial buildings by identifying the vulnerability of various representative building types based on their characteristics and dividing them into vulnerability classes. The building stock was statistically assigned to these classes based on simple characteristics such as the number of storeys or the construction period. This, combined with information on the people and assets affected, makes it possible to determine the consequences for residents and the financial losses. The latter are expressed as a proportion of the building reinstatement costs. The majority of Swiss buildings were not built in accordance with the currently applicable building standards for earthquake-resistant construction.
In addition, improved data on the amplifying effects of the subsoil conditions provide a significantly better picture of local impacts. The data include the amplifications relative to the reference rock for earthquakes recorded at 245 seismic stations in Switzerland in the years 2000-2022. The shear-wave velocity profiles and natural ground frequencies measured at numerous sites helped to model the observed amplifications.
The technical report 'Earthquake Risk Model of Switzerland (ERM-CH23)' provides comprehensive documentation about the risk model.