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Part 12. IAEA Training Material on Radiation Protection in Nuclear Medicine. Protection of the General Public. Objective.
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Part 12 IAEA Training Material on Radiation Protection in Nuclear Medicine Protection of the General Public
Objective To become aware of the BSS requirements for the protection of the public and how these are applied to restrictions in the care of the nuclear medicine patients as well as the design and operation of a nuclear medicine facility Part 12. Protection of the general public
Contents • Dose limits • Design considerations • The patient • Special problems • Transportation Part 12. Protection of the general public
Exposure of the General Public • Spread of contamination outside the department • Lost sources • The nuclear medicine patient • Disposal of radioactive waste • Transportation of sources Part 12. Protection of the general public
Responsibilities of the Government (BSS: Interim Edition) • Requirement 29: The government or the regulatory body shall establish the responsibilities of relevant parties that are specific to public exposure, shall establish and enforce requirements for optimization, and shall establish, and the regulatory body shall enforce compliance with, dose limits for public exposure. Part 12. Protection of the general public
Responsibilities of the Government (BSS: Interim Edition) “3.118. The government or the regulatory body shall establish the responsibilities of registrants, licensees, suppliers, and providers of consumer products in relation to the application of requirements for public exposure in planned exposure situations. 3.119. The government or the regulatory body shall establish and enforce requirements for the optimization of protection and safety for situations in which individuals are or could be subject to public exposure. 3.120. The government or the regulatory body shall establish or approve constraints on dose and on risk to be used in the optimization of protection and safety for members of the public. When establishing or approving constraints in respect of a source within a practice, the government or the regulatory body shall take into account, as appropriate” Part 12. Protection of the general public
Module 12.1. Dose Limits IAEA Training Material on Radiation Protection in Nuclear Medicine Part 12 Protection of the General Public
Public Exposure: Dose limits • As per Schedule III-3 of BSS (Interim Edition, 2011) for public exposure, the dose limits are: • (a) An effective dose of 1 mSv in a year; • (b) In special circumstances, a higher value of effective dose in a single year could apply, provided that the average effective dose over five consecutive years does not exceed 1 mSv per year; • (c) An equivalent dose to the lens of the eye of 15 mSv in a year; • (d) An equivalent dose to the skin of 50 mSv in a year. Part 12. Protection of the general public
Dose Constraints If nationally not available, the local Radiation Protection Committee, should establish appropriate dose constraints. Part 12. Protection of the general public
Module 12.2. Design ConsiderationsWorking Procedures IAEA Training Material on Radiation Protection in Nuclear Medicine Part 12 Protection of the General Public
Public Exposure ConsiderationsBSS: Interim Edition “3.126. Registrants and licensees in cooperation with suppliers, in applying the principle of optimization of protection and safety in the design, planning, operation and decommissioning of a source (or for closure and the post-closure period for waste disposal facilities), shall take into account: • (a) Possible changes in any conditions that could affect exposure of members of the public, such as changes in the characteristics and use of the source, changes in environmental dispersion conditions, changes in exposure pathways or changes in values of parameters used for the determination of the representative person; • (b) Good practice in the operation of similar sources or the conduct of similar practices; • (c) Possible buildup and accumulation in the environment of radioactive substances from discharges during the lifetime of the source; • (d) Uncertainties in the assessment of doses, especially uncertainties in contributions to doses if the source and the representative person are separated in space or in time.” Part 12. Protection of the general public
Reduce the Risk of Uncontrolled Contamination • Classification of areas • Well trained staff • Documented safe procedures in the handling of radiopharmaceuticals (receipt, preparation, administration, waste disposal) • Workplace monitoring Part 12. Protection of the general public
Layout of a Nuclear Medicine Department From high to low activity Part 12. Protection of the general public
CLASSIFICATION OF AREAS • Controlled area • Supervised area Part 12. Protection of the general public
Control of Visitors(BSS: Interim Edition) “3.128. Registrants and licensees, in cooperation with employers where appropriate: • (a) Shall apply the relevant requirements of these Standards in respect of public exposure for visitors to a controlled area or a supervised area; • (b) Shall ensure that visitors are accompanied in any controlled area by a person who knows the measures for protection and safety for the controlled area; • (c) Shall provide adequate information and instructions to visitors before they enter a controlled area or a supervised area so as to provide for protection and safety for visitors and other individuals who could be affected by their actions; • (d) Shall ensure that adequate control is maintained over the entry of visitors to a controlled area or a supervised area, including the use of signs for such areas. Part 12. Protection of the general public
Patient Areas • Separation of radioactive patients and other patients waiting is an • example of good practice, especially in a busy department. • Separate toilet room for the exclusive use of injected patients should • always be considered. This patient washroom should not be used by • general public or hospital staff as it is likely that the floor, toilet seat and sink faucet handles will be contaminated frequently. Part 12. Protection of the general public
Structural Shielding • The absorbed dose is determined by factors such as: • source strength; • length of exposure; • distance from the source; • transmission through the protective barrier. Patient with I-131 General public D mSv/h 0.3 mSv/procedure Distance d Part 12. Protection of the general public
Storage of Sources • locked to prevent unauthorized use • and theft • warning sign • shielded to <2 uSv/h at 1m • (permanently occupied areas) • alternatively <20 uSv/h at 1 m • (temporarily occupied areas) • inventory record Part 12. Protection of the general public
Radioactive Waste: BSS Interim Edition “3.131. Registrants and licensees, in cooperation with suppliers, as appropriate: • (a) Shall ensure that any radioactive waste generated is kept to the minimum practicable in terms of both activity and volume; • (b) Shall ensure that radioactive waste is managed in accordance with the requirements of these Standards and the requirements of other applicable IAEA standards, and in accordance with the relevant authorization; • ……… • (d) Shall ensure that activities for the predisposal management of and for the disposal of radioactive waste are conducted in accordance with the requirements of applicable IAEA standards, and in accordance with the authorization; • (e) Shall maintain an inventory of all radioactive waste that is generated, stored, transferred or disposed of; • (f) Shall develop and implement a strategy for radioactive waste management and shall include appropriate evidence that protection and safety is optimized.” Part 12. Protection of the general public
Discharge of Radioactive SubstancesBSS: Interim Edition “3.132. Registrants and licensees, in cooperation with suppliers, in applying for an authorization for discharges, as appropriate: • (a) Shall determine the characteristics and activity of the material to be discharged, and the possible points and methods of discharge; • (b) Shall determine by an appropriate pre-operational study all significant exposure pathways by which discharged radionuclides could give rise to exposure of members of the public; • (c) Shall assess the doses to the representative person due to the planned discharges; • (d) Shall consider the radiological environmental impacts in an integrated manner with features of the system of protection and safety, as required by the regulatory body; • (e) Shall submit to the regulatory body the findings of (a) to (d) above as an input to the establishment by the regulatory body…” Part 12. Protection of the general public
Module 12.3. The Patient IAEA Training Material on Radiation Protection in Nuclear Medicine Part 12 Protection of the General Public
The Radioactive Patient Uncontrolled radioactive source that causes external exposure and contamination of the general public? YES! (after leaving the hospital) Part 12. Protection of the general public
The Radioactive Patient Contamination External saliva perspiration breath urine 0.5 0.1 0.06 0.03 mSv/h 1000 MBq I-131 0 0.5 1 2 m Part 12. Protection of the general public
The Radioactive Patient Release the patient with restrictions Exposure of general public Release the patient without any restrictions Keep the patient in the hospital Part 12. Protection of the general public
Patient Survey The dose rate at 1 m fromthepatient should be down to an acceptablelevelestablished by the RPC. Hospitalize: • >1100 MBq I-131 Release with restrictions: • Treatment of thyrotoxicosis • Pain palliation (Sr-89, Sm-153) • Lactating women (specified procedures) Release without restrictions: • Diagnostic procedures Part 12. Protection of the general public
INSTRUCTIONS TO OUT-PATIENTS(Example to minimize exposure of the general public) • Use only a WC and flush 2-3 times. Keep the toilet and the floor clean. • Wash Your hands frequently and take a shower every day. • Avoid close contact to members of the family, children and pregnant women etc according to the time table attached • Avoid solid waste Off work: 6d Avoid close contact withchildren and pregnant women: 20 d Public travel: 1h/day (1st week) Part 12. Protection of the general public
Module 12.4. Special Problems IAEA Training Material on Radiation Protection in Nuclear Medicine Part 12 Protection of the General Public
Death of Patient In the event of death of a patient who has recently received a therapeutic dose of a radionuclide care has to be taken to ensure that personnel receive as low dose as possible at all stages prior to the burial or cremation. Activity (MBq) (UK) Part 12. Protection of the general public
Death of Patient • Precautions that should be given are depending on the residual activity • and the expert advice provided by the RPO and may involve the following: • preparation for burial or cremation should be controlled by a • competent person, • relatives should be prevented from coming into close contact with the • body, • people should not be allowed to linger in the presence of the coffin, • all personnel involved in handling the corpse should be instructed by • the RPO and monitored if appropriate, • all objects, clothes, documents etc that might have been in contact • with the deceased must be tested for contamination, • it may be expedient to wrap the cadaver in waterproof material • immediately after death to prevent spread of contaminated body fluids, • embalming of cadavers should, if possible, be avoided, • autopsy of a highly radioactive cadavers should be restricted to the • absolute minimum Part 12. Protection of the general public
Module 12.5. Transportation IAEA Training Material on Radiation Protection in Nuclear Medicine Part 12 Protection of the General Public
Transport Container Cartoon Liner Sealed can Liner Lead container Source Part 12. Protection of the general public
Transport Container Part 12. Protection of the general public
Transport Index (TI) 1.0 m TI = max dose-rate @ 1.0m (Sv/h) 10 Part 12. Protection of the general public
White-I Label • < 5.0 Sv/h @ surface • < 0.05 Sv/h @ 1.0 m • TI = 0 Part 12. Protection of the general public
Yellow-II Label • < 500 Sv/h, > 5 Sv/h @ surface • < 10 Sv/h @ 1.0 m • 0 < TI < 1.0 Part 12. Protection of the general public
Yellow-III Label • > 500 Sv/h,< 2000Sv/h @ surface • > 10Sv/h, < 100Sv/h @ 1.0m • 1.0 < TI < 10 Part 12. Protection of the general public
Vehicle Placards 3 placards on vehicle Part 12. Protection of the general public
Consignor’s Responsibilities all labelling and placarding provision of transport documents provision of local rules and any other relevant information Part 12. Protection of the general public
Internal Transport If the administration of radiopharmaceutical to the patient takes place far from the dispensing room, use a transport container with absorbent pads. Make sure that a warning sign is on the container together with patient name, activity and date. Travel by the most direct route avoiding more heavily occupied areas Part 12. Protection of the general public
Questions? Part 12. Protection of the general public
Discussion You get a phone-call from a colleague in another hospital about 0.5 h away. He is in an urgent need of Tc99m-MAA for a lung scan. Can you help him? Part 12. Protection of the general public
Discussion You get a phonecall from a relative to a patient whoyesterday got 4 GBq Sm-153. The patient died at hometoday. What to do? Part 12. Protection of the general public
Discussion A patient has received 300 MBq I-131 in a treatmentof thyrotoxicosis. She is working in a school preparingfood for the children. She was told to stay off work for2 weeks. You get a message that she actually wentback to work the day after the treatment, which was10 days ago. What to do? Part 12. Protection of the general public
Where to Get More Information • Other sessions • Part 4. Security of Sources, Design of Facilities • Part 5. Occupational Protection • Part 6. Medical Exposure • Part 8. Optimization of medical exposure. Therapeutic Procedures • Part 10. Radioactive Waste • Further readings • IAEA Basic Safety Standards: Interim Edition (2011) • IAEAModel regulations on radiation safety in nuclear medicine • WHO. Manual on Radiation Protection in Hospitals and General Practices. Volume 4: Nuclear Medicine Part 12. Protection of the general public