ISO 11031:2016 establishes general methods for calculating seismic loads to be used as defined in the ISO 8686 series and for proof of competence as defined in ISO 20332, for the structure and mechanical components of cranes as defined in ISO 4306.ISO 11031:2016 evaluates dynamic response behaviour of a crane subjected to seismic excitation as a function of the dynamic characteristics of the crane and of its supporting structure.The evaluation takes into account dynamic effects both of regional seismic conditions and of the local conditions on the surface of the ground at the crane location.The operational conditions of the crane and the risks resulting from seismic damage to the crane are also taken into account.It is restricted to the serviceability limit state (SLS), maintaining stresses within the elastic range in accordance with ISO 20332.It does not extend to proofs of competence which include plastic deformations. When these are permitted by agreement between crane supplier and customer, other standards or relevant literature taking them into account can be used.