NBN EN 948:1999

This European standard applies to all vertically hinged or pivoted doors. The standard specifies the method to be used to determine the permanent deformation caused when static stress in torsion is applied to an open door leaf fixed in its own door frame as part of a doorset. Note: Such torsional stresses that might reasonably be expected, such as in attempts to free a door which sticks, should neither damage nor impair the performance of a door.