Local Rules in Dental Radiography

As discussed in the previous step, one of the requirements of IRR17 is that a controlled area should be designated while dental X-ray equipment is in a state of readiness to emit X-rays. Where controlled areas are designated, it is mandatory to have local rules in place. The local rules document the safe working arrangements and administrative controls intended to restrict doses to individuals working in a radiation-controlled area, and other persons who may be affected.

The length and complexity of the local rules should reflect the nature and magnitude of the radiation hazard. For dental radiography they should be fairly simple, a couple of pages should be sufficient. Most importantly, the local rules should be clear and succinct. You must consult your RPA when they are drafted, and you should also consult your RPA if there are any changes to the X-ray equipment or working procedures that might require changes to the local rules.

Generally, a single ‘local rules’ document is sufficient to cover all types of dental radiography at a practice (intra-oral, panoramic, cephalometric, and dental CBCT). However, a practice could choose to have separate sets of local rules for each surgery containing an X-ray set, or for different types of X-ray equipment.

Essential Content of Local Rules

IRR17 requires that, as a minimum, the local rules must contain the following information:

• A description of the designated area. For example, “the whole of each room containing an X-ray set is a controlled area when the equipment is in a state of readiness to emit X-rays.”
• A summary of working instructions. The local rules must provide the instructions to be followed to ensure safe working in the area. These may include where the operator of an X-ray set should stand during exposures, intraoral X-ray beam directions to be avoided, and the “written arrangements” that staff must follow when they enter the controlled areas.
• The dose investigation level (DIL). The dose investigation level must be stated in the local rules.
• Name of the appointed radiation protection supervisor (RPS). The local rules must contain the name of the RPS(s).
• The contingency plans. Where the risk assessment has identified the need for contingency plans to follow in the event of reasonably foreseeable radiation incidents, these must be described in the local rules.

Other matters might also be included in the local rules, such as;

• Arrangements for pregnant employees
• Instructions for staff regarding personal dosimetry
• Details of how to contact the RPA

Making Staff Aware of the Local Rules

The local rules must be made available to all staff who are affected by, or likely to be affected by, the work with ionising radiation. The best way to make staff aware of the requirements of the local rules to staff is by the RPS holding a briefing session with staff groups. Details of these briefing sessions (names of those attending and the date) should be recorded and they should be repeated whenever any changes are made to the local rules. Local rules can also be made accessible on the practice electronic document management system or posted in each room containing an X-ray set.