5.2 QA programme for X-ray equipment

The employer is required by IRMER17 to establish a QA programme, in consultation with the MPE, to ensure that equipment remains capable of the adequate restriction of patient dose.

The QA programme must include the following:

• An inventory of all dental X-ray equipment and ancillary equipment which would influence the dose to the patient
• Adequate testing before the first clinical use (commonly known as ‘acceptance testing’)
• Routine retesting at appropriate intervals and following any major maintenance
• In-house checks where appropriate (see sections 5.2.4 and 5.2.5)
• Representative measurements of patient dose
• Remedial and suspension levels for action

It should be noted that IRR17 also requires the employer to have a QA programme for the maintenance and examination of engineering controls; guidance on this is set out in section 2.20.

5.2.2 Adequate testing IRMER17 requires the employer to undertake adequate testing (‘acceptance testing’) before X-ray equipment is put into clinical use. The purpose of this is to confirm that the equipment is operating correctly and is capable of the adequate restriction of patient dose. Installers often provide acceptance testing on behalf of the user at the same time as the critical examination (required under IRR17), and employers should confirm with the installer that both the critical examination and acceptance test will be carried out, and a report of the results provided, before clinical use commences. If this is not the case, the employer should consult its MPE regarding alternative arrangements (see sections 2.9, 3.7 and 6.1).

5.2.3 Routine testing and tests after repairs or modifications
Routine tests should normally be carried out at intervals not exceeding three years, except in the following circumstances where annual testing is recommended, subject to the advice of the practice’s MPE:

• Patient doses consistently exceed the relevant NDRL despite previous recommendations to reduce the dose
• Image quality analysis indicates a persistent failure to meet the targets specified in section 5.4.1 (or other targets set in consultation with the practice’s MPE where appropriate)
• For dental CBCT eqipment, where no suitable QA test object (see Appendix I2) is available
• For hand-held dental X-ray equipment, in all cases

Annual testing should be maintained until the MPE advises that acceptable performance has been restored or achieved.

Testing should also be carried out following any repairs or modification of the equipment that could significantly affect image quality or patient doses. Examples include:

• Relocation of X-ray equipment (including re-installation in the same location, e.g. following surgery refurbishment)
• Replacement of the X-ray tubehead or other important feature which will affect radiation dose
• Upgrading of existing equipment to include additional modalities, e.g. of panoramic equipment to introduce cephalometric or dental CBCT capability (even if this involves purely a software upgrade)

If in doubt, the MPE should be consulted regarding the need for, and scope of, any testing following repairs or modification. The potential need for a critical examination should also be considered by the person installing, repairing or upgrading the equipment, who should consult their RPA on this matter (see section 2.9).

Appendix I details the recommended content of acceptance tests, routine tests and tests after repair or modification and the relevant action levels and suspension levels.