Inspection report: Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights (R21/02066)
|Inspection report details|
|Licence holder:||Australian Nuclear Science and Technology Organisation (ANSTO)|
|Location inspected:||Gamma Technology Research Irradiator (GATRI), Lucas Heights, NSW|
|Date of inspection:||12, 18, 25 February 2021|
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 F0243.
The scope of the inspection included an assessment of ANSTO’s performance in regard to the facility performance objectives and criteria (PO&Cs). The inspection consisted of a review of records, interviews, and physical inspection of the facility.
The GATRI facility is comprised of two separate gamma irradiators both utilising Co-60 sources. The main irradiator is a wet storage (pool-type) irradiator while the secondary irradiator is a commercially acquired self-contained dry storage irradiator located in an adjacent annex of the building. ANSTO is currently actively pursuing a replacement for the pool-type irradiator using accelerator-based technology.
The main codes and standards applicable to this facility are those that appear in section 59 of the Regulations plus:
- Australian/New Zealand Standard: Safety in laboratories Part 4: Ionizing radiations (AS/NZS 2243.4:2018)
- Radiation Health Series 24: Code of practice for the design and safe operation of non-medical irradiation facilities (1988) (RHS 24)
Performance reporting and verification
ANSTO is required by Licence Condition 2 of Schedule 2 of Facility Licence F0243 to conduct a self-assessment, at least every three years, against applicable codes and standards. This should have been completed by end of November 2019. However, this was not done for all relevant codes and standards until end of October 2020. While the review has now been completed, this is a potential non-compliance.
ANSTO has an internal process for the review and approval of safety risks associated with activities and facilities. This formerly used the Safety Assurance Committee (SAC), however, now uses a different process known as the Safety and Reliability Assurance (SRA). The SAC approval for the operation of GATRI and the Gammacell facilities expired on 7 February 2021. The facility will need to be reassessed in accordance with the SRA process. This may rely on support from other parts of ANSTO. The facility continues to operate despite the lapse of internal approval. This matter is reflected in area for improvement 1 below.
ANSTO has an auditing program in place. The scope includes environmental and safety issues that may impact on compliance with ISO standards or regulatory requirements. However, the regulatory requirements examined appear to be limited to those imposed by the Therapeutic Goods Administration (TGA). A systematic program of internal and/or external auditing against the requirements relevant to radiation protection and with regard to the conditions imposed under the ARPANS Act 1998 may improve performance and compliance in that ANSTO will be better able to identify its own problems, report them, and rectify them - as required by sections 56 and 57 of the Regulations - along with any other common weaknesses. This matter is reflected in area for improvement 1 below.
The GATRI facility was built in 1969 and commissioned in 1970. This is prior to the publication of RHS 24. ANSTO has routinely been assessing the risks associated with the facility since 2002. The risk assessment conducted in 2012 made recommendations to improve safety. They were not implemented as the perceived life of the facility at the time was three to four years.
It was observed during the previous ARPANSA inspection in 2017 that the facility did not comply with all of the requirements of RHS 24. Specifically, there is no multipurpose key as required under paragraph 8.2 of RHS 24. Following this inspection ARPANSA and ANSTO exchanged correspondence on the matter. ANSTO indicated that a review into the operational future of the facility was to be undertaken and that if the facility life were to be extended for any significant amount of time that upgrades to the multipurpose-key would need to be implemented in order to realign the facility with the requirements of RHS 24 and in accordance with international best practice. In 2018 ANSTO conducted a self-evaluation of compliance with the requirements of RHS 24. This identified three other areas of non-compliance. Despite not meeting RHS 24, ANSTO concluded that the current arrangements were either satisfactory/adequate, meeting the intent of the RHS 24, or that making changes could lead to adverse safety outcomes. Although this was supplied to ARPANSA, it appears that no approval was sought from, or given by, ARPANSA. The long term nature of this matter in conjunction with the previous attempt to rectify it using the lowest level of enforcement and the consequences should an accident occur mean that the inspector will adopt alternate means of addressing the matter in accordance with ARPANSA’s Compliance Manual. As such, this matter will be dealt with separately from this inspection through issuing an improvement notice.
ANSTO’s risk assessment considered a few exposure scenarios. This assesses the radiological consequences of the scenario (in broad terms) and the likelihood of the event occurring. Accident scenarios which would result in substantial doses are assessed to be extremely unlikely to occur or not credible. IAEA General Safety Requirements (GSR Part 4 - Rev. 1) Safety Assessment for Facilities and Activities observes that both deterministic and probabilistic analyses have been shown to complement one another. Furthermore, GSR Part 4 - Rev. 1 indicates that conservatism in the deterministic approach compensates for uncertainties in the performance of equipment and in the performance of personnel, by providing a sufficient safety margin. Similarly, the Independent Safety Review of ANSTO Health recommended that ANSTO modify its safety assessment approach to focus on deterministic assessment during activities such as risk approval and awareness. This matter is reflected in area for improvement 2 below.
Minor amendments and improvements to the safety related documentation associated with the facility are routinely made. However, the design and operations of the facility are fairly static. One particular change was made in recent years. This was the replacement of chemicals for managing the water chemistry with a reverse osmosis system. This change was assessed and documented within the facility specific management system. While there is no suggestion that this change had significant implications for safety, the facility specific management system does not require the user to consider regulatory requirements for making changes that could have significance for safety. Such assessment is required under other ANSTO documentation. This matter is reflected in area for improvement 2 below.
The GATRI irradiator holds 100 Co-60 sources on a one square metre array. These sources were manufactured at various times from 1983 to 2008. Similarly, the Gammacell irradiator holds 24 Co-60 sources which were manufactured in 1996. ARPANSA has published guidance drawing attention to the importance of monitoring the integrity of the encapsulation for sealed sources to ensure that they do not leak radioactivity. This is communicated on the ARPANSA website and uses the concept of recommended working life (RWL) to create an awareness of the need for regular inspection and reasonable judgements to be made about the continued suitability of a sealed source as it ages. Where a recommended working life (RWL) for a source has not been set by the manufacturer, as appears to be the case in this instance, ARPANSA’s guidance indicates that 15 years should be used for Co-60 sources. The 17 sources that have most recently been loaded into the GATRI irradiator are still within their first RWL and this accounts for more than half the activity in the irradiator. However, 64 sources have exceeded one RWL and a further 19 sources have exceeded a second RWL. Similarly, all of the sources in the Gammacell irradiator have exceeded one RWL. ARPANSA has set out the expectation that licensees who wish to use sealed sources beyond one RWL will request approval on a case-by-case basis taking into account the specific factors relevant to the integrity of the source encapsulation. Although ANSTO is conducting frequent checks to confirm that the source encapsulation is sound, there has been no formal correspondence with ARPANSA to confirm the continued adequacy of the surveillance measures as the source ages. This matter is reflected in area for improvement 1 below.
Inspection testing and maintenance
Planned maintenance of the facility is undertaken on a weekly, monthly, 3 monthly, 6 monthly, and annual basis. The specific tasks to be undertaken at each period are defined in the maintenance instruction and recorded in checklists tailored for each maintenance period. Maintenance work is signed off by both the worker who performed the task and, later, the supervisor. This arrangement was implemented following an audit by the TGA. While this is recorded as ‘verification’, it does not involve physically verifying the tasks or that key safety or quality measures have been put in place. However, some verification tasks are also undertaken, for example verifying the radiation field uniformity following possible movement of the source rods. The differentiation between verification activities and supervisor review of documentation was not immediately evident.
Maintenance is largely undertaken by one very experienced worker. In some instances, the work involves overriding interlocks to perform tasks. Details of the tasks are listed in the maintenance instructions. The instructions contain operational notices and warning notices but no hazard warning is present at the relevant points in the documentation to notify the worker (or any other worker) that they are about to undertake a high risk task and the possible consequence of not following the instruction. Such warnings can be particularly valuable when training staff, or when a staff member not as familiar with the task needs to undertake it. This could, for example, occur if the staff member who routinely performs the task is unavailable. The Independent Safety Review of ANSTO Health recommended that ANSTO implement warnings of this nature. ARPANSA encourages licensees to learn from the operating experience of other facilities. This matter is reflected in area for improvement 2 below.
Each of the individuals who work at the facility is required to undertake routine generic training in radiation safety. This is a 4-hour course and includes an examination. Details showing the completion of the course are recorded in ANSTO’s corporate Learning Management System (LMS) which is used to manage mandatory training and optional staff development. The LMS records for each worker were reviewed with a focus on identifying any outstanding courses relevant to the safe management of the facility. All mandatory training within this system was completed. However, it was identified that none of the personnel had yet undertaken a recently introduced course on guidance values for restricting radiation exposures in emergency situations. Furthermore, the facility manager had not yet undertaken training in the safety assurance process, and the roles and responsibilities associated with being a facility officer, a licensing officer, or source responsible officer. None of the above courses that had not been completed were mandatory for safety.
A separate local system is used to manage the facility specific training. This is based on the documentation in the quality system for the facility. The processes are broken into tasks and a structured methodology applied to the training for each task, including to observe, perform under supervision, and perform independently at a later date. This is signed off by both the trainer and the trainee for each task. A worker’s record showed that training was provided for all tasks relevant to the worker’s role. However, a small number of tasks were marked as overdue for refresher training. This training had apparently been conducted but the records had not been updated to reflect this. This is an example where an effective internal audit program may identify matters, rectify them in a timely manner, and lead to implementation of improved management arrangements - this is captured as part of area for improvement 1.
The GATRI facility has separate safety/risk assessments for each of the irradiators and a common Safety Analysis Report (SAR). A variety of external events have been analysed. These included, loss of offsite power, earthquake, high winds, flooding, lightning strike, aircraft crash, external fire or explosion, radiological accident in adjacent building, transport accidents, industrial accidents, and military activities.
The analysis of the aircraft crash points to the prohibition of civil and military aircraft from entering the airspace above the site. The analysis also argues that as the building housing the facility is of low height, and a direct aircraft crash on the building is incredible. However, no analysis to support this was provided or referenced in the documentation. Other initiating events include external fire impacted on the facility. In this case the analysis was limited to fires originating from adjacent buildings and did not include or reference an analysis of the impact of bushfire - even though the facility is less than 100 metres from the tree line of the adjacent national park. It is important to clearly capture and document the assumptions underpinning an assessment of risk. Where site-wide risks are assessed in other documentation this should be made clear. This matter is reflected in area for improvement 3 below.
ANSTO site security includes local Australian Federal Police (AFP) response. As part of the ongoing arrangements between the two organisations, ANSTO has recently reviewed the requirements to ensure that the service provided by the AFP has the capacity and capability required to perform their function.
ANSTO performs a number of exercises and tests across the ANSTO site, the learnings from which may be applied to GATRI. No GATRI-specific security exercise had been conducted prior to the inspection. However, ANSTO’s security has previously responded to what was determined, following investigation, to be a false alarm at the facility.
ANSTO is required by section 59 of the Regulations to comply with Radiation Protection Series No. 11 Code of Practice for the Security of Radioactive Sources (2019) (RPS 11). This requires sources such as GATRI to have security plans which have been endorsed by an accredited assessor. The previous inspection identified that the security plan for the facility had not been endorsed by an accredited assessor as required by RPS 11. Furthermore, the previous inspection identified that the internal review and approval process for the security plan had not included the ANSTO Security Advisor. While there is no evidence to suggest that the security arrangements previously in place were inadequate for the situation, the need to demonstrate appropriate arrangements to an external and independent entity is consistent with similar requirements for radiation protection and nuclear safety and displays effective organisational governance. Since the inspection in 2017, the facility has obtained endorsement from an accredited assessor and engaged with the ANSTO security team.
The security plan for the facility identifies and assesses a variety of security risks, some of which have radiological consequences. ANSTO has a process for managing and communicating security risks. This includes escalation to the risk and audit subcommittee of the ANSTO Board. This escalation of risks within the ANSTO organisation is different to the process for managing and communicating safety risks. This matter is reflected in area for improvement 3 below.
The operation and maintenance of the facility are largely conducted by a small team of two workers and a facility manager. Personal dosimetry, in the form of thermoluminescent dosimeters (TLD) and electronic personal dosimeters (EPD), are worn. The TLDs are used to formally evaluate the worker’s doses while the EPDs provide a real-time measurement and the capacity to alarm in a situation where a high dose rate is present (i.e. an accident condition). The normal exposures received by workers in recent times have been low. Although the facility is not at its maximum radiological capacity, an accidental exposure resulting in a worker being exposed to an unshielded source could have fatal consequences.
The principle of optimisation of protection requires that the likelihood of incurring exposures, the number of people exposed and the magnitude of the exposures should be all kept as low as reasonably achievable, taking into account economic and societal factors. Optimisation should be forward looking and an ongoing cyclical process. A facility-specific dose constraint of 2 mSv/year has been established. It is normal practice within ANSTO to conduct retrospective analysis of worker doses received over time against dose constraints. In this instance, ANSTO has not documented any consideration of the optimisation of the facility let alone a cyclical program of review. Optimisation is a broad activity and includes potential exposures as well as normal exposures. ICRP Publication 75 explicitly states that “potential exposures could occur if there is a failure of equipment or a breakdown in procedures, including the failure of human beings to follow them. The optimisation principle should apply to the design of equipment to prevent or reduce the probability of accidents or incidents that could lead to radiation exposures, to the measures aimed at mitigating the consequences should such accidents or incidents occur, and to the procedures that workers are required to follow”. This matter is reflected in area for improvement 3 below.
Emergency preparedness & response
ANSTO has a hierarchy of emergency plans in place covering the facility, the site and at the organisational level. There is awareness of the interfaces between the various emergency plans in place, and the roles, responsibilities and other documented arrangements are being reviewed to ensure that they are accurate and aligned. The objective at the corporate level is to build the organisational capacity and test it via a multi-facility and multi-agency exercise.
The facility has been conducting emergency exercises for over twenty years. The approach has evolved over time and has tested a variety of different scenarios. There has only been one emergency exercise since 2018. There is typically a meeting immediately afterwards to discuss the exercise and identify any amendments to the emergency plan accordingly.
Audible and visible alarms are present at the facility and are duplicated in the adjacent building and would be expected to alarm in the event of an emergency. Should this occur, staff are expected to gather at one of the designated muster points. The nearby muster point for building evacuations was moved last year following the calculation of gamma dose rates in the vicinity of the facility for what was considered to be a worst-case emergency scenario. By exercising the emergency arrangements, ANSTO could confirm that staff respond as written in the plan. This matter is reflected in area for improvement 3 below.
The inspection revealed the following non-compliance/s:
- Not conducting a self-assessment against all applicable codes and standards every three years as required by licence condition 2 of Facility Licence F0243.
The inspection revealed the following areas for improvement:
- The internal audit and process improvement functions.
- The facility-specific change management system.
- The assessment, communication and documentation of radiological risks.
It is expected that improvement actions will be taken in a timely manner.