Codes of practice common questions

An actual or suspected pregnancy notified by an employee to an employer is not considered to be a reason for the employee to be excluded from work on radiation safety grounds.

Clause 8 the Code of Practice for Industrial Radiography ORS C7 2019 requires managing entities to establish, implement and maintain procedures and local rules. This includes receiving and responding to a notification of an actual or suspected pregnancy.

Procedures and local rules should be directly derived from the safety assessments that managing entities need to conduct and periodically review under clauses 2(b)(i) and 8(l) of ORS C7 2019. Safety assessments must, among other things, review potential occupational exposures from the use of a radiation source or from reasonably foreseeable incidents involving radiation.

In carrying out a safety assessment the managing entity must consider that Schedule 3 the Radiation Safety Act 2016 (the Act) applies a dose limit of 1 mSv (effective dose) in a year to an embryo or a foetus. In relation to a worker, the safety assessment needs to recognise the potential during industrial radiography for this dose limit to be exceeded.

Also, the managing entity will need to specify and implement procedures and local rules to inform persons occupationally exposed to radiation of the applicable dose limits, and to facilitate and support notification to an employer of an actual or suspected pregnancy.

Schedule 3(3) of the Act means that working conditions for a person during the term of the person’s pregnancy will be such that the level of protection from radiation is broadly the same to that required for a member of the public.

If it is required, the employer and the employee will need to agree adapted working conditions for the employee to satisfy radiation safety requirements.

This is a job specific consideration. The minimum for any site radiography job is one licensed radiographer and a radiography assistant. However, the radiography team must be able to ensure at all times during radiography no unauthorised persons enter the controlled area (and if they do it is noticed immediately and the source is wound in).

For smaller controlled areas with clear visibility of the boundaries this may be achieved with a team of two. For larger more complex controlled areas, particularly those involving multiple levels then additional personnel will be needed to patrol the controlled area.

Yes. These personnel would be working under the direct supervision of the lead radiographer. Sufficient direction would need to be given by the radiographer to ensure they can work safely. The radiographer must be physically present and able to intervene. These personnel would have to be provided with personal dosimeters and treated as other radiation workers in terms of dose monitoring and recording (unless all their activities can be performed outside of the controlled area).

You must notify the ORS of the change of storage location using the prescribed form. The location of the cameras and sources must be accounted for at all times and recorded in the movement log.

There are two aspects to consider when securing a gamma camera inside an enclosed vehicle during transport: security and physical restraint. Some methods of restraint address both aspects simultaneously, and these are listed here in order of most secure to least secure:

• inside a locked toolbox that is bolted or welded to the vehicle
• within a locked metal frame that is bolted or welded to the vehicle
• locked chain (>7mm) through the handles or other secure fixing point so that is also adequately restrained from movement to secure eyelets that are bolted or welded to the vehicle.
• The camera must not be left unattended for long periods of time as these security measures assume a degree of supervision by the radiographer.

Yes. There should be no need to restrict access around the x-ray equipment for pregnant operators. However, best practice would be to issue a personal dosimeter primarily for reassurance purposes.

For x-ray inspection equipment that complies with all the technical requirements in terms of features such as shielding, interlocks, radiation warning lights, preventing access to the primary beam and so on, then the safety assessment should show that operators are afforded the same level of protection as members of the public in terms of radiation exposure. Note that public dose limits are set to protect the most vulnerable in society, notably the unborn child.

This can easily be demonstrated by performing a radiation survey around the operating x-ray unit.

The public dose limit of 1mSv per year and the public dose constraint of 0.3mSv per year will be achieved if the dose rate is less than 0.5µGy/h (0.5 µSv/h), averaged over an area of 100cm² at positions 5cm outside the shielding.

You need to perform a safety assessment to determine whether there is potential for receiving significant radiation doses (greater than 1/10 of the relevant dose limit). If the equipment is designed, maintained and operated properly, and the dose rate in accessible areas is less than 0.5uSv/h then radiation doses should be very low, well below the 1/10 threshold and therefore personal dose monitoring would not normally be necessary.

However, it may be beneficial to perform individual dose monitoring to provide reassurance. These can help demonstrate that radiation exposures are being properly restricted and are especially useful for new users and during pregnancy.

There are also requirements for general workplace monitoring and these can normally be met through the normal radiation surveys at commissioning, after servicing/maintenance and during the regular safety audit.

Yes, there needs to be at least one use licensee. Other operators may work under the direct supervision or written instruction of the use licence holder. Note, the managing entity must also hold a source licence.

Managing entities must ensure all operators have sufficient training to perform their duties safely by regularly reviewing competencies and providing refresher training. There is no specified refresher training frequency, but should be done every few years to keep operators familiar with changes to working techniques, equipment and legislation.

The equipment must only be repaired/maintained by properly trained and authorised persons. Equipment should be immediately taken out of use if it is suspected of being damaged or any of the safety and warning systems are not working.

If the equipment is not being sent back to the manufacturer for repair then the maintenance must be performed by a service engineer with a valid user licence for servicing and installation of irradiating apparatus.

You need to perform a safety assessment to identify any area that needs special controls for managing the radiation exposure, and this area must be designated as a controlled area. For hand held analysers the area 3 to 5 metres in the path of the primary beam and 1 metre to each side of the device would need to be a controlled area due to the elevated radiation levels.

The safety assessment above would also identify that personal dosimetry is required for handheld XRF operators due the operator being within the controlled area during measurements. The most appropriate dosimeter would be a finger TLD.

For other analysers that are not hand held then a trial period post commissioning with a whole body dosimeter to establish workplace exposure would be appropriate.

The levels in Appendix 3 of C11 2020 are not disposal limits, they are levels above which the managing entity must carry out an assessment to show that the public dose limits will not be exceeded for a proposed disposal via air, sewer or landfill and submit a waste management plan to the Director.

First, reference is made to Schedule 2 of the Radiation Safety Act 2016, as discharges below these levels are too low to even be considered radioactive material for the purposes of the Act and may be discharged without further consideration.

Appendix 3 of ORS C11 2020 provides for higher discharges under certain conditions. For discharges in excess of those listed in Appendix 3 the managing entity is required to produce a waste management plan and have it approved by the Director for Radiation Safety. Approved waste management plans demonstrate how discharges will not lead to public dose limits being exceeded.