Advisory Statement A18/04 - Introduction of Revised Diagnostic Reference Levels for Computed Tomography

Page last updated: 26 June 2018

PDF version: Advisory Statement A18/04 - Introduction of Revised Diagnostic Reference Levels for Computed Tomography (PDF 352 KB)


To provide information about the introduction of revised adult diagnostic reference levels (DRLs) for computed tomography and clarify the requirements for annually comparing facility reference levels to the newly revised DRLs.


In 2015, the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) established computed tomography DRLs for six anatomical regions. Following a recent review of the current DRLs by a Liaison Panel, comprising representatives from key professional groups, ARPANSA will publish revised computed tomography DRLs for eight anatomical regions, namely head, cervical spine, soft-tissue neck, chest, abdomen-pelvis, kidney-ureter-bladder, chest-abdomen-pelvis, and lumbar spine.

The revised DRLs will be published on the ARPANSA website and will come into effect from1 July 2018.


Standard 3.2, Optimised Radiation Technique Charts Standard of the Diagnostic Imaging Accreditation Scheme (DIAS) requires a practice providing services which use ionising radiation to establish a program to ensure that radiation doses administered to patients are

  • annually compared with DRLs for diagnostic imaging procedures for which DRLs have been established in Australia, and
  • if DRLs are consistently exceeded, a review is undertaken to determine whether radiation protection has been optimised.

The introduction of revised DRLs for computed tomography will require practices providing Medicare-funded computed tomography services to compare their facility references against the new DRLs.

For the purposes of the DIAS, practices providing computed tomography services will not be required to submit audit records relating to the new DRLs until 1 January 2019.

In the period to 1 January 2019, practices are expected to review their dose metrics and facility reference levels and include the new DRLs in their practice policy. Until 31 December 2018, practices have the option of comparing their facility reference levels against either the previous DRLs or the new DRLs.

From 1 January 2019, as part of an application for accreditation (including renewal of accreditation), accreditors will require evidence that policies for undertaking a DRL comparison have been updated and that computed tomography audits conducted after this date have been compared against the new DRLs.

For more information

Enquiries relating to the calculation of DRLs and the operation of the National Diagnostic Reference Level should be directed to ARPANSA by calling 1800 033 972 or by emailing

Practices should also refer to the DIAS User Guide for Practices Applying for Accreditation for clarifying information about the evidentiary requirements for Standard 3.2, and contact their accreditor for further information and advice.