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Part 4. IAEA Training Material on Radiation Protection in Nuclear Medicine. Safety of Sources Design of facilities. OBJECTIVE.
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Part 4 IAEA Training Material on Radiation Protection in Nuclear Medicine Safety of Sources Design of facilities
OBJECTIVE To become familiar with the types of sources used in nuclear medicine. To become aware of how the basic principles of defence in depth, safety of sources and optimization are applied to the design of a nuclear medicine facility. To get basic information about shielding calculations. Part 4. Design
Content • Sources • Work with sources • Security of sources • Defense in depth • Categorization of hazard • Building requirements • Safety equipment Part 4. Design
Part 4. Design of facilitiesSafety of Sources IAEA Training Material on Radiation Protection in Nuclear Medicine Module 4.1. Sources
Sealed sources in nuclear medicine Sealed sources used for calibration and quality control of equipment (Na-22, Mn-54, Co57, Co-60, Cs137, Cd-109, I-129, Ba-133, Am-241). Point sources and anatomical markers (Co-57, Au-195). The activities are in the range 1 kBq-1GBq. Part 4. Design
Unsealed sources in nuclear medicine Part 4. Design
Unsealed sources in nuclear medicine Part 4. Design
Unsealed sources in nuclear medicine Part 4. Design
RADIOTOXICITY Class A. Very high e.g. Am-241, Cf-252 Class B. High e.g. Na-22, Ca-45, Mn-54, Co-60, Sr-89, I-125, I-131 Class C. Medium e.g. C-14, F-18, P-32, Cr-51, Co-57, Ga-67, Se-75, Mo-99, In-111, I-123, Au-198, Tl-201 Class D. Low e.g. H-3, C-11, N-13, O-15, Tc-99m, Xe-133 Part 4. Design
Nuclear medicine applicationaccording to type of radionuclide Radionuclide Diagnostics Therapy • Pure emitter () • e.g. ; Tc99m, In111, Ga67, I123 • Positron emitters (ß+) • e.g. : F-18 • , ß- emitters • e.g. : I131, Sm153 • Pure ß- emitters • e.g. : Sr89, Y90, Er169 • emitters • e.g. : At211, Bi213 Part 4. Design
99Mo-99mTc GENERATOR 87.6% 99mTc 99Mo 140 keV T½ = 6.02 h 12.4% ß- 442 keV 739 keV T½ = 2.75 d 99Tc ß- 292 keV T½ = 2*105 y 99Ru stable Part 4. Design
Technetium generator Mo-99 Tc-99m Tc-99 66 h 6h NaCl AlO2 Mo-99 +Tc-99m Tc-99m Part 4. Design
Technetium generator Part 4. Design
Technetium generator Part 4. Design
Technetium generator Part 4. Design
Technetium generator Part 4. Design
Technetium generator Part 4. Design
Radiopharmaceuticals Radionuclide Pharmaceutical Organ Parameter + colloid Liver RES Tc-99m + MAA Lungs Regional perfusion + DTPA Kidneys Kidney function Part 4. Design
RADIOPHARMACEUTICALS • Radiopharmaceuticals used in nuclear medicine can be classified as follows: • ready-to-use radiopharmaceuticals • e.g. 131I- MIBG, 131I-iodide, 201Tl-chloride, 111In- DTPA • instant kits for preparation of products • e.g. 99mTc-MDP, 99mTc-MAA, 99mTc-HIDA, 111In-Octreotide • kits requiring heating • e.g. 99mTc-MAG3, 99mTc-MIBI • products requiring significant manipulation • e.g. labelling of blood cells, synthesis and labelling of radiopharmaceuticals produced in house Part 4. Design
RADIOPHARMACEUTICALS • Radiopharmaceuticallabeling must be performed in accordance with : • Radiation safety regulations • GMP requirements • Requirements of these respective regulations are sometimes conflicting : • Manipulation of radioactive material must be performed in closed area under negative air pressure • Manufacturing of sterile injectable preparation must be performed under filtered positive air pressure (laminar flow) Part 4. Design
Part 4. Design of facilitiesSafety of Sources IAEA Training Material on Radiation Protection in Nuclear Medicine Module 4.2. Work with sources
Production of radionuclides Medical cyclotron Industrial cyclotron Part 4. Design
Preparation and dispensation of radiopharmaceuticals Part 4. Design
Laboratory work with radionuclides Part 4. Design
Administration of radiopharmaceuticals Part 4. Design
Patient examinations Part 4. Design
Animal experiments Part 4. Design
CARE OF RADIOACTIVE PATIENTS Part 4. Design
Storage of radionuclides Part 4. Design
Part 4. Design of facilitiesSafety of Sources IAEA Training Material on Radiation Protection in Nuclear Medicine Module 4.3. Security of sources
LOCATION AND SITING OF SOURCES (BSS) • “IV.13. Account shall be taken in choosing the location for any small • source within installations and facilities such as hospitals and • manufacturing plants of: • Factors that could affect the safety and security of the source; • Factors that could affect occupational exposure and public • exposure caused by the source, including features such as • ventilation, shielding and distance from occupied areas; and • The feasibility in engineering design of taking into account the • foregoing factors.” Part 4. Design
Requirements for the Safety of Sources • General Responsibilities • Licensees shall ensure safety of the sources • A multilevel system of provisions for • preventing accidents • mitigating consequences • restoring sources to safe conditions • Use of sound engineering practice on all operations with sources Part 4. Design
Security of sources • BSS 2.34: “Sources shall be kept secure so as to prevent theft or damage and to prevent any unauthorized legal person from carrying out any of the actions specified in the General Obligations for practices of the Standards (see para’s 2.7-2.9), Part 4. Design
Requirements Accountability and security of sources • Records of source inventory (source characteristics, locations) • Periodic inventory of sources • Records of receipt, transfer and disposal • Transfers only to receiver holding a license • Prompt communication of information to the Regulatory Authority regarding decontrolled, lost, stolen or missing sources Part 4. Design
SECURITY OF SOURCES The security of sources shall be taken into account in the different steps of the lifetime of a source in a hospital Receipt Storage before use Transport (in house) Storage of waste Use Part 4. Design
RECEIPT PROCEDURE • Local rules should specify • Persons authorized to order radionuclides • Routines for delivering radioactive material to the department • Routines for check and unpacking of shipment • Routines in case of damaged package • Routines for check of radionuclide and activity • Records to be kept Part 4. Design
Source Storage Source stores must: • provide protection against environmental conditions • be only for radioactive materials • provide sufficient shielding • be resistant to fire • be secure Part 4. Design
STORAGE OF SOURCES • locked to prevent unauthorized use • and theft • warning sign • shielded to <2 µSv/h at 1m • (permanently occupied areas) • alternatively <20 µSv/h at 1 m • (temporarily occupied areas) • inventory record Part 4. Design
Source transport • In house transport, according to local rules. • External transport, according to international standards and requirements. Part 4. Design
RADIOACTIVE WASTE • Radioactive waste should be handled, stored and disposed of according to local rules that are based on national regulations. Part 4. Design
Accountability of sources • Receipt, storage, use and all movements of a source must be recorded Part 4. Design
Accountability of Sources Source accountancy records should contain: • radionuclide and activity of sources • location and description of sources • disposal details The records should be updated regularly, and the location of the sources checked. Part 4. Design
Safety Assessment • Identification of the mechanisms for exposure (both routine and accidents) • Realistic estimate of doses and likelihood of occurring • Identification of possible safety system failures • Identification of protection measures needed Part 4. Design
Safe use of sources Key elements • classification of areas • local rules • supervision arrangements • individual monitoring arrangements • workplace monitoring arrangements • training arrangements • emergency plans Part 4. Design
How do we transfer the requirements of BSS regarding safety and security of sources into the design of a nuclear medicine facility? ?? Part 4. Design
The role of RPO The radiation protection officer (RPO) should be consulted as soon as the planning process commences for construction or renovation of a nuclear medicine facility or other hospital radioisotope laboratory. Part 4. Design
Facilities The design of the facility should take into consideration the type of work and the radionuclides and their activities intended to be used. The concept of ‘categorization of hazard’ should be used in order to determine the special needs concerning ventilation, plumbing, materials used in walls, floors and work benches. Part 4. Design
Part 4. Safety of Sources Design of facilities IAEA Training Material on Radiation Protection in Nuclear Medicine Module 4.4. Defense in depth
DEFENSE IN DEPTH (BSS) • “2.35. A multilayer (defense in depth) system of provisions for protection and safety commensurate with the magnitude and likelihood of the potential exposures involved should be applied to sources such that a failure at one layer is compensated for or corrected by subsequent layers, for the purposes of: • (a) preventing accidents that may cause exposure; • mitigating the consequences of any such accident that does • occur; and • (c) restoring sources to safe conditions after any such accident.” Part 4. Design
Defense in depth • Nuclear medicine: • Source • Shielded container • Work area • Laboratory • Department • Hospital Weak points? Part 4. Design