|Licence holder||Department of Defence and Australian Defence Force|
|Location inspected||A Defence base in South Australia|
|Date/s of inspection||19 July 2022|
An inspection was conducted as part of ARPANSA’s baseline inspection program to assess compliance with the Australian Radiation Protection and Nuclear Safety Act 1998 (the Act), the Australian Radiation Protection and Nuclear Safety Regulations 2018 (the Regulations), and conditions of facility licence F0252.
The scope of the inspection included an assessment of Defence’s performance against the Performance Objectives and Criteria (POC) and applicable codes and standards. The inspection consisted of a review of records, interviews, and physical inspection of the facility.
Defence, being the organisation responsible for defending and protecting Australia and advancing its strategic interests, has the need to test explosive ordinance. As such, Defence holds a 1.2-3 MeV linear accelerator (linac) which is used to perform non-destructive testing (NDT).
The main codes and standards applicable to this facility are those in section 59 of the Regulations, and:
- Australian Standard Safety in Laboratories - Ionizing Radiations (AS 2243.4)
- Health Physics Society (HPS) Installations using non-medical x-ray and sealed gamma-ray sources, energies up to 10 MeV (ANSI/HPS N43.3-2008)
Performance reporting and verification
Since the previous inspection in 2020, no radiation safety events have occurred at the facility.
The process as identified in the previous inspection report, R20/10969, remains in place whereby reports are recorded electronically (i.e., Sentinel) and the chain-of -command is always kept informed as appropriate. Safety events that require reporting to ARPANSA would be done through the Defence Radiation Safety Assurance function which undertakes radiation safety compliance monitoring on behalf of Defence as a whole.
As required by licence condition 2 of F0252, Defence continues to report quarterly to ARPANSA.
No significant physical changes have occurred at the facility since 2020.
Since the last inspection, an updated version of the safety case has been incorporated at the facility as well as a revised Radiation Safety Plan (RSP) through which Defence incorporates the required Plans and Arrangements legislated by the Regulations. No issues were identified on review of these documents.
Through a desktop review, ARPANSA inspectors noted that the terms ‘radiation incident’ and ‘radiation accident’ are incorporated in multiple documents. Inspectors informed Defence that there has been a recent move away from the term ‘accident’ given that its application does not fit with the intent of the Planned Exposure Code soon to be reflected in changes to the Regulations. Defence will incorporate this change through their document review process.
Fail-safe lighting as per AS 2243.4 was also discussed. The facility has incorporated a newer lighting system with failure preventing operation of the linac until it has been replaced. Though the previous system looked to meet the intent of the Australian Standard, this improvement is considered to now address the requirement.
Inspection, testing and maintenance
Arrangements for maintenance of the facility remain unchanged. Varian, the original equipment manufacturer, continue to perform the contracted maintenance function for Defence as scheduled and when required.
Maintenance performed by Defence staff is considered part of non-technical inspections. Staff do not perform any technical maintenance on the linac or its associated equipment. Any works not directly related to the linac itself but rather the physical facility in which it sits will be performed by the appropriate Defence contractor.
The previous inspection identified an area for improvement (AFI) in relation to the inspection, servicing and testing of emergency stop devices and interlocks. Since 2020, the facility continues to perform the previously implemented test but has since captured further testing of the other interlocks (inclusive of facility doors, light sensors, etc.) to address the AFI.
Defence is also currently in the process of improving its maintenance management system to include the linac. This will allow for the implementation of a tracking regime specific to the inspection, testing and maintenance of the equipment.
Given that there is little to no turnover of staff at the facility, radiography personnel have remained unchanged in recent years. As such, non-destructive testing and radiation safety competencies continue to be upheld through appropriate refresher training.
Given the nature of the site and the facility, the likelihood of any credible accident scenario with radiological consequences as a result of an external event is deemed unlikely.
Security at the site is commensurate with that which would be expected of a defence base and remains unchanged.
The base is guarded and patrolled by Defence personnel with the linac residing in one of the many buildings present. The facility itself exists within a fenced off and gated area under the control of contracted security personnel.
Only those authorised or escorted (after approvals have been granted) are given access to the facility with all others removed prior to radiography commencing. Further to this, only those authorised to obtain facility access keys are able to do so. Moreover, systems are in place to control and track each key.
In the 2-year period between inspections, there have been no unusual dosimetry results beyond what is expected in relation to the existing workload or trends through dose reporting. No dose levels warranting further action or investigation have been reached or exceeded in either passive or real-time measurements.
Radiation surveys continue to be performed in accordance with procedure using calibrated survey equipment. No issues were identified.
Emergency preparedness and response
No change has occurred in relation to emergency preparedness and response for the facility since 2020. Procedures dictate various methods employed to shut down the linac in the event of an emergency. No issues were identified.
A response to a radiation/x-ray incident remains in planning stages however should be exercised in a timely manner.
The licence holder was found to be in compliance with the requirements of the Act, the Regulations, and licence conditions.
It is expected that improvement actions discussed at the time of inspection will be taken in a timely manner.