Management of radioactive substances Flashcards
What are the three pieces of legislation that cover the storage and disposal of radioactive materials?
- Ionising Radiation Regulations 2017 (IRR17).
- Radiation (Emergency Preparedness and Public Information) Regulations 2019 (REPPIR).
- Environmental Permitting Regulations 2016 + 2018 amendment (EPR).
What aspects of IRR17 relate to storage and disposal of radioactive materials?
- Discharging radioactive materials into the environment.
- Radiation risk assessments.
- Design, maintenance and leak testing of sealed sources.
- Accounting for and keeping records of radioactive substances.
- Keeping/storage and moving of radioactive substances.
- Notification of certain occurrences (e.g. spillage or release causing significant contamination or loss or theft that exceeds limits).
What aspects of REPPIR 2019 relate to storage and disposal of radioactive materials?
Information must be made publicly available and appropriate emergency preparations made. However, this is only for activities over a specified level. This means these regulations will not apply to most nuclear medicine departments.
What aspects of EPR relate to storage and disposal of radioactive materials?
- Radioactive substances regulations.
- Generation and disposal of radioactive waste.
- Permitting prior to commencement of work. Based on radiological assessments. Single permit covers storage and disposal.
What does an EPR permit cover?
- Operations: Work that is covered and scope of the work. Radionuclides and maximum activities permitted to store on site (including low limit of non-standard radionuclides).
- Accumulation of radioactive waste: Waste radionuclide types (including decay products), activity limits, volume limits and time period limits (including low limit of non-standard radionuclides).
- Disposal of radioactive waste: Disposal (via air, sewer, transfer to other premises or incineration) waste radionuclide types (including decay products) and annual/monthly/daily limits.
What must be completed for an EPR permit to be obtained? What is the purpose? What is it used for?
- Environmental impact assessment.
- Purpose: Initial assessment of dose arising from sources of radioactive waste discharges to the environment. Identify areas for which a more detailed assessment should be undertaken.
- It is used to define the limits in the permit.
What factors are considered within an environmental impact assessment? What can help with the environment impact assessment?
- Properties of waste radionuclides (e.g. state, radiological properties such has half-life, chemical properties such as water solubility, activity released etc.).
- Waste route: Landfill/sewer/release to atmosphere, how the waste is processed, dose to waste workers, dose to groups downstream of waste facility.
- Initial radiological assessment tool (IRAT) can help identify critical groups and calculate dose to wildlife.
What information may need to be gained from local water treatment facilities for aqueous waste?
Flow rates through the water treatment works.
What can be used to help determine dose to critical groups from waste?
Dose per unit release tables in IRAT provide dose estimates for relevant radionuclides, critical groups and exposure pathways.
After the initial radiological assessment, when is a more in-depth assessment required? Where can additional information for more-depth assessment be found?
- Dose >= 300 microSv/yr.
- EA provide additional tables with more detailed breakdowns for more in-depth assessments.
What are BATs? What do they help with?
- Best available technique.
- They are an EPR requirement.
- They aid with reducing the amount of stored and disposed radionuclides.
What are the general principles of BATs?
Operator shall use best available techniques to:
- Minimise activity on site.
- Minimise time waste is accumulated.
- Minimise activity of waste on site.
- Premises are maintained so to not become contaminated and can be easily decontaminated.
- Prevent loss of radioactive materials and access by any person who is not authorised.
- Minimise gaseous and aqueous radioactive waste disposed to environment.
- Minimise volume of waste transferred to other premises.
- Dispose of waste to minimise radiological effects to the environment.
What are some practical examples of BATs?
- Segregating waste by radionuclide type. This will reduce the volume of waste stored on site where some radionuclides can be disposed of earlier than others.
- Extend storage time for some radionuclides.
- Use alternative radionuclides.
What are some general principles of waste management?
- Detailed records of all sources must be kept.
- Accurate records of each disposal much be kept (apart from where limits for exception of very low level waste have been met). Patient excretion factors are published in IPEM for situations in which this is the mode of disposal.
- Annual return of all radioactive waste disposed of in previous year to EA.
What are the general principles of contamination monitoring in a nuclear medicine department?
- Daily contamination monitoring of all controlled areas at a minimum.
- Accurate records of all monitoring kept.
- Records of annual calibration of all contamination monitoring equipment.
