RW for decision makers on development of regulations and implementation of national radon plans TC project RER9153 Olga German, IAEA 14 – 17 January, 2019 Vienna
Objective and scope Objective: To raise awareness and understanding of requirements related to the protection of population against exposure to radon among the representative of the Governmental level decision-makers. Working method: Requirements related to the protection of population against exposure to radon and NORM, roles and responsibilities of the Governments and the Regulatory Bodies as stated in the IAEA safety standards will be presented. Practical examples of implementing these requirements will be given. National presentations and group discussions will follow to identify gaps and steps forward.
Expectations • Active participation – there are no stupid questions • Respect and attention • Information and knowledge is shared back home • Knowledge is applied in practice • Identify gaps and priorities for future work and steps needed to close the identified gaps • Facilitate cooperation among the professionals across the borders • Enjoy!
Layout of the workshop • Day 1 REQUIREMENTS • General knowledge on radon and NORM • GSR Part 3 requirements framework • GSR Part 1 requirements framework • Day 2 IMPLEMENTATION • Practical examples of implementing the requirements (Austria, Ireland, Czech Republic) • Radon Action Plan guidance • Day 3 PROGRESS REPORT • Overview of the progress report submitted by the Member States • National presentations • Day 4 PLANNIG • National presentations continued • Discussions on gaps and steps forward
General information Radon in IAEA GSR Part 3 IAEA guidance on Radon action plan IAEA requirements on Radon in workplaces
Radon Radioactive noble gas T1/2 – 3,8 days Alfa emitter (5.49 MeV)
Why is radon of concern? UNSCEAR, 2008 REPORT Vol. I Annex B Worldwide radon accounts for 3% to 16% of all lung cancer deaths, depending on the average radon concentration in the country (WHO Handbook on Radon, 2009) *International Agency for Research on Cancer Radon is a class 1 carcinogen* Radon is responsible for almost one half of total ionising radiation dose received by the pubic each year. Radon exposure can be controlled so as to reduce health effects Radon health risk is 25 times greater for people who smoke
National Average Radon – UNSCEAR 2006 UNSCEAR 2006 Report: "Effects of ionizing radiation"
National Average Radon – UNSCEAR 2006 cont’d UNSCEAR 2006 Report: "Effects of ionizing radiation"
Health effects of radon exposure When radon gas is inhaled, alpha particles from radon decay products can interact with biological tissue in the lungs leading to DNA damage.
Relative risk of lung cancer European pooling, Darby et al 2005, 2006. A smokerof 1 pack ofcigarettes per dayhas a 25 foldhigherriskoflungcancerthan a lifelongnonsmoker.
History ofhealtheffectsofradon Health effects of radon recorded in the 16th Century amongst miners in Central Europe Lung cancer in 75% ofminersfrom Schneeberg, Germany in the 19th century 1960: first epidemiological studies ofminersidentified a linear relationship between lung cancer risk and radon levels 1988: radon classified as human carcinogen by the International Agency for Research on Cancer (IARC) In the 1980s and 1990s variousepidemiologicalstudies on lungcancerriskbyresidentialradonwereconducted in Europe, North America and China 2005: two large pooledepidemiologicalstudiespublished – Darby (2005) and Krewski (2005) 2017 UNSCEAR initiatedreviewofscientificdatato update radon dose conversionfactor. Expectedpublication 2019.
Radon pathwaysintobuildings 5% - Diffusion (due to concentration gradients) 95% - Convection (due to pressure/temperature gradients) Source: www.radon.ie (EPA Ireland)
Other sources of radon in buildings • Building material • Stones, bricks, tiles always contain some amount of radionuclides including radium. • If the radium concentration is high, gamma radiation is also of concern. • Radon releases from building material into the indoor environment. • Well water • Radon dissolves in water in the geological environment. • Radon is released from water during water use, mainly through showering. • Radon is not a concern in surface water sources as the gas is released before it reaches the home. • Ingestion of radon in water is not considered a health concern.
Radon levels in buildings Radon levels indoors are influenced by: • Soil gas radon concentration • Soil permeability • Cracks and gaps in the structure • Level and type of heating/ventilation • Basement, ground, upper floors • Usage of the building including the habits of occupants • Season and weather Source: BfS Germany
Radon in soil Image K.Skeppström, KTH PRIMERY source of indoor radon Emanation 5% - Diffusion (due to concentration gradients) 95% - Convection (due to pressure/temperature gradients) Porosity and air availability Image W. ReifAlharbi
Lets have some fun! In dry clay areas 1 m3 of soil air contains 10 000 – 120 000 Bq of Radon Imagine a house/office with air volume 1200 m3 (20m*20m*3m) Air exchange rate is 0.7 volumes/hour, and 1% of this volume comes from soil beneath How much radon will come with soil air every hour? 1200 * 0.7 * 0.01 = 8.4 m3 How much radon does it bring every hour? 8,4 m3 * (10 000 to 120 000) Bq of Radon = 84 000 to 1 008 000 Bq of Radon every hour Devide by volume of house 84 000 to 1 008 000 / 1200 m3 = 70 – 840 Bq/m3 every hour passes through the volume Radon problem?
Temporal variation of indoor radon concentration Source: BfS Germany
Radon in soil and ground – use purpose-designed instruments!
Need Accredited methods according ISO 17025 and laboratory capacity Quick reliability and repeatability of measurements High testing capacity Low investment cost and low price per test Possibility for testing in situ and/or final product Minimum time loss – crucial for the industry
How come? RASSC, WASSC, NUSSC, EPRESC
Structure of GSR Part 3 1. INTRODUCTION 2. GENERAL REQUIREMENTS FOR PROTECTION AND SAFETY Application of principles of radiation protection Responsibilities of the government Responsibilities of the regulatory body Responsibilities for protection and safety Management requirements 3. PLANNED EXPOSURE SITUATIONS Scope Generic requirements Occupational exposure Public exposure Medical exposure 4. EMERGENCY EXPOSURE SITUATIONS Scope Generic requirements Public exposure Exposure of emergency workers Transition from an emergency exposure situation to an existing exposure situation 5. EXISTING EXPOSURE SITUATIONS Scope Generic requirements Public exposure Occupational exposure Schedule I EXEMPTION AND CLEARANCE Schedule II CATEGORIZATION FOR SEALED SOURCES USED IN COMMON PRACTICES Schedule III DOSE LIMITS FOR PLANNED EXPOSURE SITUATIONS Schedule IV CRITERIA FOR USE IN EMERGENCY PREPAREDNESS AND RESPONSE
IAEA Safety Standards relating to radon • SF-1: Fundamental Safety Principles (2006) • GSR Part 3: Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards (2014) Chapter 5 • SSG-32: Protection of the Public against Exposure Indoors due to Radon and Other Natural Sources of Radiation (2015) • All co-sponsored by WHO
Existing exposure situation Scope • Exposure due to contamination by residual radioactive material • Exposure due to commodities • Exposure due to natural sources • Radon in dwellings and workplaces • Aircrews and space crews - cosmic radiation
Generic requirements Requirement 47: Responsibilities of the government specific to existing exposure situations The government shall ensure that existing exposure situations that have been identified are evaluated to determine which occupational exposures and public exposures are of concern from the point of view of radiation protection.
Public exposure Requirement 48: Justification for protective actions and optimization of protection and safety • The government and the regulatory body or other relevant authority shall ensure that remedial actions and protective actions are justified and that protection and safety is optimized. • Justification of protective actions and remedial actions • Optimization of protection • Reference levels typically expressed as annual effective dose to the representative person in range of 1-20 mSv
Responsibility for remediation Requirement 49: Responsibilities for remediation of areas with residual radioactive material • The government shall ensure that provision is made for identifying those persons or organizations responsible for areas with residual radioactive material; for establishing and implementing remediation programmes and post-remediation control measures, if appropriate; and for putting in place an appropriate strategy for radioactive waste management.
Radon indoors Requirement 50: Public exposure due to radon indoors • The government shall provide information on levels of radon indoors and the associated health risks and, if appropriate, shall establish and implement an action plan for controlling public exposure due to radon indoors. • Information gathered on radon levels in dwellings and other buildings of high occupancy, • Information on radon levels and health risks is made available for the public, • Assign responsibility to a regulatory body/relevant authority, • If significant radon levels, then national action plan • Reference level for 222Rn not to exceed 300 Bq/m3 • Optimize protection • Corrective actions and preventive measures into building codes • Determine if corrective actions are mandatory or voluntary
Radionuclides in commodities Requirement 51: Exposure due to radionuclides in commodities • The regulatory body or other relevant authority shall establish reference levels for exposure due to radionuclides in commodities. • Regulatory body to establish specific reference levels for exposure to radionuclides in construction materials, food, feed, drinking water – reference level is not to exceed 1 mSv • Food traded internationally as a result of a nuclear or radiological emergency – FAO/WHO - Codex has published guideline values • Drinking water – WHO guidelines
Exposure in workplaces Requirement 52: Exposure in workplaces • The regulatory body shall establish and enforce requirements for the protection of workers in existing exposure situations. • The requirements in respect of public exposure shall be applied for protection and safety for workers in existing exposure situations, other than: • Remediation of areas with residual radioactive material - exposure of workers is planned exposure situation, • Exposure due to radon in workplaces -reference level for 222Rn - 1000 Bq/m3 , account taken of the prevailing social and economic circumstances. If, remains above the reference level – requirements of planned exposure situations shall apply. • Exposure of aircrew and space crew due to cosmic radiation - reference level of dose and a methodology for the assessment, recording of doses, information to employees. Specific requirements for occupational exposure in planned exposure situations are to apply, particularly for pregnant aircrew if reference levels are exceeded.
Definitions Reference level is the level of dose, risk or activity concentration above which it is not appropriate to plan to allow exposures to occur and below which optimization of protection and safety would continue to be implemented. The chosen value for a reference level will depend upon the prevailing circumstances for the exposure under consideration. Dose limit is the value of the effective dose or the equivalent dose to individuals in planned exposure situations that is not to be exceeded. National authority refers collectively to the regulatory body and all the other authorities and organizations with responsibilities in relation to exposure to radiation from natural sources”, noting that “These organizations can include, but are not limited to, organizations involved in radiation protection and public health policy, public and private bodies specializing in radiation measurements, and bodies that set and implement building standards.”
Role of reference level in protection strategy To be used for optimization of protection and safety in emergency and in existing exposure situations not appropriate to plan to allow exposuresto occur - Optimized dose reduction reference level to optimize optimized level
Exposure due to radon in workplaces The regulatory body orother relevant authority shall establish a strategy appropriate reference level for 222Rn. The reference level for 222Rn shall be set at a value that does not exceed an annual average activity concentration of 222Rn of 1000 Bq/m3, On the assumption of an equilibrium factor for 222Rn of 0.4 and an annual occupancy of 2000 h, the value of activity concentration due to 222Rn of 1000 Bq/m3 corresponds to an annual effective dose of the order of 10 mSv. Employers shall ensure that ALARA and optimisation are applied. If, despite all reasonable efforts by the employer to reduce activity concentrations of radon, the activity concentration of 222Rn in workplaces remains above the reference level the relevant requirements for occupational exposure in planned exposure situations as stated in Section 3 shall apply.
Identification Rn is a part of working environment – employers at all workplaces shall be protected Measurements with long term exposure If above RL – remediate and measure again If below RL – follow up regularly If still above RL – planned exposure situation – registration or licencing, dose assessment and record keeping etc.. Be aware of mixed exposure situations Risk based approach - pay attention to underground workplaces, tunnels, tourist caves, spas, schools and kindergardens, waterworks, rock ground facilties etc
Relevant guidance SSG-32 Protection of the Public against Exposure Indoors due to Radon and Other Natural Sources of Radiation (2015) TECDOC 1810 Status of Radon Related Activities in Member States Participating in Technical Cooperation Projects in Europe (2017) Follow up report: Review of Achievements on Protection of Public against Radon Exposure to Radon Indoors (sent to NLOs and CPs) SR XX Design and Conduct of Indoor Radon Surveys (in publication) AQR 33 National and Regional Surveys of Radon Concentration in Dwellings/ Review of Methodology and Measurement Techniques (2013) TECDOCXX Radiation protection against indoor radon and building material – remediation and prevention (under development) SSG-XX Radon in Workplaces (under development) SR-XX Regulatory control of exposure due to radionuclides in building and construction materials (under development)
Other radon related work • Set of radon training material in open access • Module 1 What is radon and its health effects • Module 2 Requirements of International BSS • Module 3 Establishing a Radon Action Plan • Module 4 Representative radon survey • Module 5 Radon measurements • Module 6 Radon communication • Series of webinars planned for 2019 • Communication and promotion • Build environment and building materials • Radon risk mapping • TM on implications of new radon dose conversion factors 1-4 October 2019 • Publications planned for work 2019-2020 • SG on radon in workplaces • SR on regulatory control of building materials
Where to start? Rn survey and maps To establish Rn ref.level (carefully) Information and comunication Responsible Gov.Authority + aassignment of other responsibilities Subsidies (measurement, corrective actions?) Legislation what is reccomended what mandatory Radon industry (measurement professionals) (accreditation) BuildingProfessionals for prevetion + corr.action (licensing?) Capacity building Corrective actions (existing buildings) Prevention (future buildings) Some steps needs to be done in parallel
Radon Action Plan (GSR Part 3, SSG-32) To be coordinated with other national programmes and authorities • National radon policy • Government to assign responsibilities • Provision of information – communication strategy • National survey of radon in dwellings and public buildings • Identification of radon prone areas • Setting a reference level • For dwellings not to exceed an average annual concentration of 300 Bq/m3 • For workplaces not to exceed an average annual concentration of 1000 Bq/m3 • Control and reduction of exposure to radon • Corrective actions for existing dwellings • Corrective actions to be mandatory or voluntary • Building codes : Preventive measures for new dwellings • Evaluation of effectiveness
National Radon Action Plan • Establishment • Assign responsibilities • A national reference level not exceeding 300 Bq/m3 • Develop legal framework • Identify effective preventive measures and corrective actions • Develop communication strategy • Develop educational system for professionals (building, measurement) • Implementation • Identify radon-prone areas and develop radon maps • Include appropriate preventive measures and corrective actions in building codes for new and existing buildings • Update and implement communication strategy • Educate, licence (?) professionals • Reduce radon levels in dwellings • Review • Evaluate effectiveness of all actions and improve them accordingly.