Summary Report
Introduction
This report serves to provide a summary analysis of the data held in the Australian National Radiation Dose Register (ANRDR) until the end of 2020.
During 2020, strategic direction of the ANRDR was put in the hands of the ANRDR Advisory Board that was established the previous year.
The ANRDR also underwent some significant improvements since publication of the last ANRDR in Review in 2019 with the completion of the ANRDR Employer Interface Improvement and Data Cleansing projects for improved usability and to identify and link duplicate worker records.
Engagement continues with Dosimetry Service Providers (DSPs) and the ANRDR Advisory Board has approved the DSP Pilot Program for the ANRDR to work with the DSPs to identify and scope all the requirements for submission of DSP customer dose records to the ANRDR.
A draft accreditation scheme for DSPs operating in Australia has been developed and will include a requirement for submissions of customers’ dose records to the ANRDR. The accreditation scheme is currently awaiting approval by various committees at the state and national levels.
ANRDR Advisory Board
In the Radiation Health Committee (RHC) meeting held in November 2019 the establishment of the ANRDR Advisory Board was approved. This was subsequently established in early 2020 and has met twice in 2020 and once in 2021.
The primary purpose of the ANRDR Advisory Board is to represent all jurisdictions when dealing with ANRDR matters and to provide advice to ARPANSA on the development and national expansion of the ANRDR. The Advisory Board serves to provide recommendations to the CEO of ARPANSA on the strategic direction of the ANRDR. The ANRDR Advisory Board is made up of ANRDR Team Members from ARPANSA and appointments from several jurisdictional regulators.
During its second meeting of 2020, the Advisory Board approved the ANRDR Strategic Directions 2020 – 2025 which articulates the ANRDR revised vision and objectives. The ANRDR Strategic Directions plan also details a pathway for the ANRDR to obtain dose records directly from dosimetry service providers via direct engagement and a series of projects, as well as other programs of work in progress.
Updated ANRDR Vision
The ANRDR vision is to provide the long-term storage and retrieval of radiation dose records for all individuals who are monitored for occupational exposure in Australia.
Updated ANRDR Objectives
The objectives of the ANRDR are to:
- ensure dose records for all workers are consolidated and easily accessible for them
- identify and promptly communicate dose limit exceedances to the employer and regulator for workers who have changed jobs or have more than one employer
- provide employers with access to their workers’ dose records for their current employment through the ANRDR as a free record management tool plus industry and occupation-specific statistics for occupational exposures
- provide regulators with oversight of all exposures in their jurisdiction, including statistical breakdowns
- allow dosimetry service providers to submit dose records easily to the ANRDR
- remain flexible to adapt to accessibility expectations for all stakeholders
- meet international best practice for the long-term storage and maintenance of dose records in a national register
ANRDR Projects
In late 2019 the ANRDR implemented the Employer Interface Improvement project to improve the quality of information provided to the ANRDR and provide employers with access to their submitted records and new reporting functionality. ANRDR users will now be able to access the following reports:
- worker registration reports containing the details and ANRDR numbers of registered workers
- personalised ANRDR registration certificates containing the registered details and ANRDR numbers for dissemination to workers
- access to previously uploaded files to ensure organisations meet their dose record-keeping requirements.
Additionally, the registration process for new users has been simplified and the following modifications have been made to the data transfer file format:
- The ability to include workers’ ANRDR registration numbers (now called National Dosimetry Numbers) for improved person matching
- Additional fields have been included to collect information relating to:
- Dosimetry service provider(s)
- Dose assessment methodologies
- Other key information such as the use of protection factors
Occasionally multiple entries are created in the system for individuals if some of the personal information does not match the existing information in the register. During 2020 the ANRDR completed the Data Cleansing Project to cleanse the register of multiple entries of individuals and combine their dose records into one single registry item. This work was required as a follow on from the Employer Interface Improvement Project due to the way that the database tables were restructured during that first project.
The data cleansing work resolved a range of issues including:
- Reducing the manual processing of matched individuals
- Removing approximately 20,000 multiple entries for individuals
In 2021, consultation on the Dosimetry Service Provider Pilot Program was launched in conjunction with the ANRDR Data Assimilation Project, the aim of this work is to facilitate the submission of dose records directly from dosimetry service providers into the ANRDR. This would be in conjunction with the existing ANRDR ability to obtain dose records directly from employers. This model is preferred for the collection of doses from organisations that perform their own dosimetry for some exposure pathways, like internal exposures in mining.
Currently this work is progressing well with the development of the systems in progress and commitment and feedback received from all operating dosimetry service providers in Australia.
Analysis of data
The ANRDR collects information on quarterly-assessed radiation doses for a range of dose types and exposures. Some personal information is also collected to allow us to match workers with their doses and to identify workers when they request their dose history reports. The data collected is used to monitor individual doses and generate annual statistics related to exposure trends. This may assist with the optimisation of radiation protection practices for workers.
The ANRDR currently holds the dose records for more than 48,000 individuals, primarily from the uranium industry, but also the mineral sands industry, government organisations, and veterinary and medical practices. This report provides an analysis for doses submitted from the uranium industry and ARPANSA’s licence holders.
ARPANSA acknowledges that doses below the minimum reporting limits from dosimetry service providers are entered into the ANRDR as a zero value, which causes the statistical results to skew downward. The ANRDR team are continuing to investigate alternative analysis methods for future editions that would more accurately represent average doses for industries and work categories. Analysis methods used to report results here are in line with those used for other national dose registers around the world and used by international bodies such as the International Atomic Energy Agency (IAEA) and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR).
Uranium Industry Data
The ANRDR has coverage of all licenced Australian uranium operators with exposure records for all operations from 2011. Doses reported in this report are derived from the official methodology used in each operation.
Figure 1 shows the trends for the average and maximum effective doses combined for workers in all work categories. The average effective dose for workers decreased from 0.82 mSv in 2019 to 0.76 mSv in 2020 while the maximum decreased from 10.3 mSv to 6.6 mSv.
Figure 2 shows the trends for average effective doses for the work categories of mining, processing and other (including administrative and other support staff). When compared with the previous year, 2020 data shows a slight increase in the average effective dose for workers in the processing and other categories, while a decrease has been observed in the average effective dose for workers in the mining category. The average effective doses for mining, processing and other for 2020 are 1.2 mSv, 0.4 mSv and 0.4 mSv respectively.
Collective Effective Dose
The collective effective dose can be used as a comparative tool for the optimisation of radiation protection practices. It has been used by UNSCEAR for reporting and comparing exposures from different practices around the world (UNSCEAR 2008).
The collective effective dose is simply the sum of the individual doses incurred by a group and is expressed as ‘person-sieverts’ (person Sv), to distinguish the collective dose from the individual dose (IAEA 2007). More recently, the term ‘person-sieverts’ is becoming common in place of the traditional unit of ‘man-sieverts’ (man Sv). The collective effective doses from the uranium industry are shown in Figure 3.
Commonwealth organisations
Reported doses
Since an amendment was made to the ARPANS Regulations in 2017, all relevant Commonwealth organisations must submit dose records to the ANRDR. The ANRDR team continues to work with ARPANSA licence holders to ensure their submission to the ANRDR. Since mandatory submissions to the ANRDR have been required since 2017 the review period for this report dates from 2017 – 2020 and is shown below in Figure 4.
The four largest submitting organisations include the Australian Nuclear Science and Technology Organisation (ANSTO), the Commonwealth Scientific and Industrial Research Organisation (CSIRO), the Australian National University (ANU) and the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA). These organisations consist of scientific research, regulatory authorities, university research, nuclear installations and other source licence holders. For this review the work categories have been selected as scientific research, university nuclear facilities and miscellaneous (regulatory and other source licence holders).
Top 100 doses for Commonwealth organisations
As previously reported in the 2019 ANRDR in Review, a review of the top 100 doses from submitting Commonwealth organisations can help regulators to tailor their inspection regime and facilitate discussions with their licence holders. The top 100 doses from Commonwealth organisations are provided in Figure 5 and range from 0.89 – 3.74 mSv with an average of 1.42 mSv in 2020.
Dose distribution
The data from all organisations submitting to the ANRDR has been analysed to produce the dose distribution histogram for 2020 provided in Figure 6. This is an effective way to demonstrate the distribution of occupational exposure and can minimise the impact of data skewing for doses that have been reported as less than the minimal reportable dose (<MRD). The average effective dose for all workers in the ANRDR in 2020 was 0.54 mSv with a maximum dose of 6.63 mSv.
Analysis of the cumulative frequency of the doses reported to the ANRDR for 2020 shows that 81% of workers have received a dose less than 1 mSv and approximately 98.8% have received a dose of less than 3 mSv in comparison with the occupational exposure limit of 20 mSv per year. No reported workers received a dose approaching even half the occupational exposure limit.
Conclusion
This ANRDR in Review has focused on analysis of the data available in the ANRDR until the end of 2020. A range of organisations continue to submit to the ANRDR, and it maintains complete coverage of the Australian uranium mining industry. Projects implemented in the last few years have improved ANRDR functionality and a range of database administration functions.
The addition to the ANRDR of submissions directly from dosimetry service providers will ensure the ANRDR achieves its vision to capture all doses for occupationally exposed workers in Australia. This process will become a requirement as part of the future DSP accreditation scheme.
The analysis of data provided in this report demonstrates that occupational exposure to ionising radiation in Australia is well controlled.
