IEC 60601-2-44:2009 applies to the basic safety and essential performance of CT scanners. The scope of IEC 60601-2-44:2009 is limited to CT scanners intended to be used for both head and body characterised by an enclosure of the X-ray source(s) and imaging detector(s) in a common protective cover in the shape of a toroid. It includes safety requirements for the X-ray generators used in CT scanners, including those where high-voltage generators are integrated with an X-ray tube assembly. This third edition cancels and replaces the second edition published in 2001 and its Amendment 1 (2002). This edition constitutes a technical revision primarily related to radiation protection and control. The contents of the corrigendum of May 2010 have been included in this copy.