This European Standard specifies a method of determining the mechanical performances of prefabricated components made of autoclaved aerated concrete (AAC) according to prEN 12602 or lightweight aggregate concrete with open structure (LAC) according to prEN 1520 under longitudinal load which may be combined with transverse load. These performances include: - the deflections and maximum crack width in the serviceability limit state; - the loadbearing capacity (failure load); - the load-(vertical) deformation diagram, if required.