Code of Practice for Dental Radiology: ORS C4

Published online: 
28 June 2018

This Code of Practice for Dental Radiology is issued by the Director for Radiation Safety under section 86 of the Radiation Safety Act 2016. It provides details necessary to comply with the fundamental requirements in sections 9 to 12 of the Act. Appendix 2 sets out cross-references between clauses in this code and those fundamental requirements. The requirements in this code do not limit the general nature of the fundamental requirements.

This code came into force on 28 June 2018.


This code applies to all activities associated with radiological equipment used for intra-oral, panoramic and cephalometric dental procedures. Activities associated with cone beam computed tomography equipment will be dealt with in ORS C1: Code of Practice for Diagnostic and Interventional Radiology. Activities can include manufacturing, possessing, controlling, managing, using, transporting, storing, exporting, selling, supplying and disposing of equipment.

Compliance with the code does not imply compliance in related areas such as health practitioner clinical competence, occupational safety, hazards in the workplace, resource management and transport of hazardous substances.


Under the old Radiation Protection Act 1965 all dentists were required to hold a user licence and, as a condition of that licence, were required to comply with the code of safe practice CSP7. Under the new Radiation Safety Act 2016 the Director is authorised to issue codes of practice that apply to everyone who deals with radiation sources irrespective of whether or not they are licensed. The new code therefore applies to all dental practitioners and their organisations.

Consultation process

In 2016 the Ministry released a document for public consultation. This was notified widely including to all dentists who held licences under the old Act. The consultation period closed on 28 October 2016. 50 individual submissions were received that were specific to the dental code.

In addition the Ministry has consulted on other codes relating to radiology, medical therapy, nuclear medicine and non-medical uses of radiation sources. The Ministry is mindful of the need to consistency across all codes and has therefore taken account of submissions made for all codes in order to develop final consistent documents.


The main change under the new Act relates to imposing the primary responsibility for radiation protection and safety on the organisation that manages or controls radiation sources. The previous Act only allowed for the licensing of individual users. The new code confirms this change in prime responsibility and sets out the requirements that organisations must satisfy.

Requirements are also imposed on dental practitioners relating to the justification and optimisation of dental procedures and on suppliers and servicing engineers. In all cases these are consistent with international recommendations.

The most significant change relating to X-ray equipment is increase in minimum tube potential for intra-oral equipment from 50 to 60 kVp. Again this is consistent with international requirements and the Ministry is not aware of any equipment that doesn’t satisfy the new level. If there is any such equipment then the Act allows for exemptions to be granted although practices really should be striving to use equipment that satisfies the new requirement.

What this means for practice

Most dental practices will notice little or no change as a result of these changes. In many cases the practitioner and the organisation are closely related and radiation safety functions are likely to continue to be performed by the same person as before. In larger organisations the redistribution of functions between the owner and the practitioner will require a reassessment of roles to ensure that all requirements are satisfied. The Ministry is aware that these discussions have been taking place for some time now.

What about guidance notes?

The previous code contained a mixture of ‘shalls’ and ‘shoulds’ to distinguish between regulatory requirements that must be complied with and recommendations that are not mandatory. The new Act specifies that the codes set out requirements that must be complied with. The Ministry is therefore working on a separate guidance document to assist practitioners and organisations to understand and comply with the new requirements. Among other things this draft document includes is a consolidation a number of articles issued by the former National Radiation Laboratory in the ‘dental drill’ series.

Publishing information

  • Date of publication:
    28 June 2018
  • ISBN:
    978-1-98-853965-2 (online)
  • HP number:
  • Citation:
    Ministry of Health. 2018. Code of Practice for Dental Radiology: ORS C4. Wellington Ministry of Health.
  • Ordering information:
    Only soft copy available to download
  • Copyright status:

    Owned by the Ministry of Health and licensed for reuse under a Creative Commons Attribution 4.0 International Licence.

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