This part of IEC 60068 provides methods of test applicable to specimens which, during transportation, storage or in service, can be subjected to low air pressure. The object of the low air pressure test is to the determination of the ability of components, equipment or other articles to be used, transported or stored at low air pressure. For components, equipment or other articles to be used, transported or stored under a simultaneous combination of high or low temperature and low air pressure where the combination is important for the stresses imposed on the articles or for the failure mechanisms, shall then be tested according to IEC 60068-2-39.