Does a dental practice need a radiation protection adviser?

Yes. A dental practice in Great Britain with X-ray equipment must consult a suitable radiation protection adviser (RPA) under regulation 14 of the Ionising Radiations Regulations 2017, and appoint the RPA in writing, stating the scope of advice. Northern Ireland's 2017 regulations carry the same duty. The dental Guidance Notes list it among the essential actions for starting X-ray work.

The Ionising Radiations Regulations 2017 (IRR17) and the Ionising Radiation (Medical Exposure) Regulations 2017 (IR(ME)R) are the law. HSE's Approved Code of Practice to IRR17, published in its book L121, has special legal status: if you are prosecuted and did not follow it, you must show you complied with the law in some other way. The HSE guidance printed alongside it is not compulsory, and following it will normally be enough to comply. The Guidance Notes for Dental Practitioners on the Safe Use of X-ray Equipment use "must" for a legal requirement or the Approved Code of Practice, and "should" for recommended practice. This page keeps the same split.

Does a dental practice legally need a radiation protection adviser?

Regulation 14(1) of IRR17 says every employer engaged in work with ionising radiation "must consult such suitable radiation protection advisers as are necessary" to advise on the Regulations. It must also, in any event, consult one on the matters in Schedule 4.

The one exemption is regulation 14(3). An employer whose only work with ionising radiation is listed in Schedule 1 need not consult an RPA. HSE's registration page names "X-ray devices used by dentists" among the work that needs registration, and IRR17 regulation 6 excludes from registration a practice solely doing Schedule 1 work. Read together, a dental X-ray set is outside the exemption. The dental Guidance Notes state the duty in their list of essential actions for a practice starting X-ray work: "Appoint a suitable radiation protection adviser (RPA) to advise on IRR17".

Once the employer consults an RPA under regulation 14(1), it must appoint that RPA in writing, and the appointment must set out the scope of the advice. HSE guidance adds that a first consultation, held only to ask whether formal consultation is needed, does not need a written appointment. The employer must give the appointed RPA adequate information and facilities to do the job.

The Guidance Notes say legal responsibility for compliance with IRR17 and IR(ME)R rests with the employer and cannot be delegated to any other person. The RPA is also a separate appointment from the radiation protection supervisor, whom regulation 18 has the employer appoint for work in areas under local rules.

IRR17 extends to England, Wales and Scotland. Northern Ireland has the Ionising Radiations Regulations (Northern Ireland) 2017, whose regulation 14 carries the same duty to consult an RPA. The Guidance Notes say their references to IRR17 and IR(ME)R also cover the very similar Northern Ireland legislation.

What must the practice consult the RPA about?

Schedule 4 of IRR17 names four matters on which the employer must always consult an RPA:

1. Putting in place the requirements for controlled and supervised areas.
2. Examining plans for installations before they are built, and accepting new or modified sources of ionising radiation into service, as to their engineering controls, design features, safety features and warning devices.
3. Regular calibration of equipment that monitors levels of ionising radiation, and regular checks that it works and is used correctly.
4. Periodic examination and testing of engineering controls, design features, safety features and warning devices, and regular checks of systems of work.

Beyond those four, regulation 14(1) requires consultation wherever advice is needed to comply with IRR17. The Approved Code of Practice says this should include the radiation risk assessment, the designation of controlled and supervised areas (unless there is good reason to think none is needed), the investigations the Regulations require, contingency plans, and dose assessment and recording.

For dental radiography the Guidance Notes list twelve matters for RPA advice. Five are printed in bold, and the Guidance Notes say consultation on those is specifically required under regulation 14(1). They say the RPA's advice should cover the other seven as relevant to dental radiography.

The Guidance Notes also say an RPA must be consulted when existing X-ray equipment is moved or significantly modified, or when the room construction, layout or working arrangements change, and relying solely on the advice of the supplier or installer of the equipment is not appropriate. The radiation risk assessment must be carried out in consultation with an RPA before any new work with ionising radiation starts, and again when anything relevant to radiation safety changes. The local rules must be drafted following consultation with the RPA.

HSE guidance tells employers to get written confirmation of any key advice from the RPA, as evidence of consultation. The Guidance Notes say advice on the listed matters should be given in writing. They also say an RPA may help with HSE registration but is not allowed to complete it for the employer.

None of the sources on this page sets a visit schedule for the RPA. IRR17, the Approved Code of Practice and the dental Guidance Notes tie consultation to the listed matters and to changes in the work. HSE guidance says an RPA appointed on a continuing basis should be available whenever consultation is required under the access arrangement agreed with the employer, and does not need to be present every time work with ionising radiation takes place. The Guidance Notes recommend an ongoing appointment so advice can come promptly. They also recommend an annual review of the local rules, carried out in consultation with the RPA.

Who can act as an RPA, and how is that recognised?

IRR17 defines an RPA as an individual or a body that meets criteria of competence specified in writing by HSE. Those written criteria are HSE's Statement on radiation protection advisers.

An individual meets HSE's core competence in one of two ways:

• a certificate of core competence from an assessing body HSE recognises
• a level 4 National or Scottish Vocational Qualification (N/SVQ) in radiation protection, which HSE's RPA page says must have been issued within the last five years

HSE's list of recognised assessing bodies, checked on 23 September 2026, has one entry: RPA 2000. HSE says RPA 2000 was set up by the Society for Radiological Protection, the Institute of Physics and Engineering in Medicine, the Institute of Radiation Protection and the Association of University Radiation Protection Officers. Its certificates are reassessed periodically, normally every five years.

An organisation can hold the role too. HSE calls a body that meets its criteria an RPA Body and publishes a list of the RPA bodies it recognises. An individual RPA can be a part-time or full-time employee or a consultant.

A certificate shows core competence only. HSE's recognition of an individual RPA is not tied to any sector, and its Statement says holding a certificate or N/SVQ "does not, of itself, make the holder a suitable RPA". HSE's RPA page tells employers to check that the RPA they choose meets the criteria in the Statement and has the relevant experience for the advice they need. For dentistry the Guidance Notes set that test as "specific knowledge and adequate experience of radiation protection as applied to diagnostic radiology in the dental sector".

In Northern Ireland the criteria of competence may be specified by the Health and Safety Executive for Northern Ireland or by HSE.

How does the RPA differ from the medical physics expert under IR(ME)R?

The two roles sit under different regulations. The RPA advises the employer on IRR17. The medical physics expert (MPE) advises on IR(ME)R, the regulations on medical exposures. The dental Guidance Notes list both appointments together among the essential actions for a practice starting X-ray work.

IR(ME)R regulation 14(1) says the employer must ensure a suitable MPE is appointed and involved for every type of exposure the Regulations cover. IR(ME)R defines an MPE as an individual or group with the knowledge, training and experience to act or advise on radiation physics applied to exposure, whose competence is recognised by the Secretary of State.

For dental radiography the MPE is involved as appropriate for consultation on optimisation. The MPE advises on dosimetry and quality control, on physical measurements for evaluating dose, and on medical radiological equipment. The MPE also contributes to quality assurance of the equipment, acceptance testing, technical specifications and installation design, the use of diagnostic reference levels, the analysis of accidental or unintended exposures, the training of practitioners, operators and other staff, and advice to the employer on IR(ME)R compliance. The MPE must, where appropriate, liaise with an RPA.

The regulation and the Guidance Notes differ in wording here. The Guidance Notes, published in 2020, list "Dosimetry and QA" among the MPE's matters. Regulation 14 was amended from 1 October 2024 and now reads "dosimetry and quality control", and it adds operators to the staff whose training the MPE contributes to. This page follows the regulation as it stands.

DHSC's guidance to IR(ME)R says the MPE's functions are different from the RPA's, although in practice the same person may hold more than one role.

DHSC's recognition scheme uses RPA 2000 as its appointed assessing body, and the scheme page says applications to be recognised as a new MPE can be made to RPA 2000. The DHSC scheme page says RPA 2000 certificates are valid for five years. As with the RPA, recognition as an MPE does not in itself make someone suitable for a particular MPE role.

IR(ME)R 2017 extends to England, Wales and Scotland. DHSC says its IR(ME)R guidance does not apply to the Ionising Radiation (Medical Exposure) Regulations (Northern Ireland) 2018. DHSC's statement on MPE recognition cites both the Great Britain and the Northern Ireland regulations.

The sources on this page were checked on 23 September 2026.

The RPA advises on keeping the X-ray equipment safe. Take the two-minute reading test to see what you catch on the radiographs it takes.