IEC 60601-2-28:2017 applies to the basic safety and essential performance of X-ray tube assemblies and to components thereof, intended for medical diagnosis and imaging. Where the general standard IEC 60601-1 and the collateral standard IEC 60601-1-3 refer to me equipment, this is interpreted as X-ray tube assemblies in this particular standard. If a clause or subclause is specifically intended to be applicable to ME equipment only, or to ME systems only, the title and content of that clause or subclause will say so. If that is not the case, the clause or subclause applies both to ME equipment and to ME systems, as relevant. The third edition of this particular standard has been prepared to fit IEC 60601-1:2005 and IEC 60601-1:2005/AMD1:2012 (the amended third edition of IEC 60601-1), which is referred to as the general standard. Apart from the changes related to the amendment of IEC 60601-1, changes related to technical improvements are also included.