Abstract | Large-capacity atmospheric tanks are widely used to store liquids, such as oil or liquefied natural gas. The seismic risk of such industrial facilities is considerably higher compared to ordinary structures, since even some minor damage induced by a ground motion may have uncontrollable consequences, not only on the tank but also on the environment. Recent earthquakes have shown that heavy damage on tanks may lead to temporary loss of function, usually followed by leakage and/or fire. Therefore, a Performance-Based Earthquake Engineering (PBEE) framework should be employed for the seismic design and performance assessment of such critical infrastructure. Current design codes and guidelines have not fully adopted the performance-based concepts, while their application to industrial facilities is still under research. The proposed PBEE framework consists of a series of nonlinear response history analyses based on a simplified modelling of the tank. Our aim is to improve upon the existing body of work by offering a surrogate model that can be implemented with minimum effort for both anchored and unanchored tanks, for application within a PBEE framework using either static or dynamic analysis methods. In that sense, a robust sensitivity analysis is presented to acknowledge the uncertainties involved in the model presented.