Safety of road and highway infrastructures is a fundamental element of their sustainability, therefore, the National Agency for safety of railways and roads, formerly Ansfisa, has activated a series of coordinated actions aimed at reducing and managing the risks associated with road and highway infrastructures, according to the modern international guidelines which, recognizing the impossibility of guaranteeing a zero risk, establish guidelines for the management and reduction of the risks themselves.

The Italian regulatory instrument used are the Guidelines for risk classification and management, safety assessment and monitoring of bridges, adopted with Ministerial Decree no. 578 of 17/12/2020. The application of these Guidelines has highlighted various interpretative issues, resulting also by discretional approaches, not reconcilable with the Agency needs of uniformity, supervision and certification. Therefore, within the scope of its competences, the Agency has proposed appropriate Operating Instructions.

The preparation of an interpretative and guidance document – drawn up in the form of operating instructions inserted in the body of the text of the current Guidelines – has the goal to identify a common and uniform approach to the multi-level procedure that, starting from the census of the assets, leads to the determination of a overall Attention Class on the basis of which to activate safety checks. The present paper, retracing the Operating Instructions, focuses on risk assessment by examining, in particular, the issue of seismic risk linked to the risk factors of the characterization of the environmental actions, vulnerability and exposure.