VIII.3. Optimization of Protection for Medical Exposures in Nuclear Medicine 1. Design considerations Postgraduate Educational Course in Radiation Protection and the Safety of Radiation Sources

According to the BSS II.11. The requirements for the safety of sources specified in other parts of the Standards shall also apply to sources used in medical exposure, where relevant, and, in particular, equipment used in medical exposure shall be so designed that: (a)failure of a single component of the system be promptly detectable so that any unplanned medical exposure of patients is minimized; and (b)the incidence of human error in the delivery of unplanned medical exposure be minimized.

According to the BSS (cont) II.12. Registrants and licensees shall: (a) taking into account information provided by suppliers, identify possible equipment failures and human errors that could result in unplanned medical exposures; (b) take all reasonable measures to prevent failures and errors, including the selection of suitably qualified personnel, the establishment of adequate procedures for the calibration, quality assurance and operation of diagnostic and therapeutic equipment, and the provision to personnel of appropriate training and periodic retraining in the procedures, including protection and safety aspects; (c) take all reasonable measures to minimize the consequences of failures and errors that may occur; and (d) develop appropriate contingency plans for responding to events that may occur, display plans prominently, and periodically conduct practice drills.

Authorized services Considering that, according to the BSS, the activities listed below also require authorization, regulatory authorities may require the licensee of a nuclear medicine practice to contract any of the following services only to enterprises authorized by the Regulatory Authority:  import, distribution, sale or transfer of radioactive sources  installation, maintenance of nuclear medicine equipment  disposal of radioactive sources

RADIOPHARMACEUTICALS l The licensee shall store, handle and use materials in accordance with manufacturer’s instructions.

RADIOPHARMACEUTICALS Radiopharmaceutical labeling 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)

RADIOPHARMACEUTICALS Sterile room negative pressure filtered air Dispensation negative pressure Corridor Injection room Fume hood Laminar air flow cabinets Passage Work bench

Safe use of sources Key elements l classification of areas l local rules l supervision arrangements l individual monitoring arrangements l workplace monitoring arrangements l training arrangements l emergency plans

Safe use of sources l The licensee shall provide appropriate equipment to contain, store and dispense unsealed sources, having due regard to radiation safety and limitation of contamination.

Safe use of sources (cont) l This includes, where appropriate, n shielded containers, n bench top shields, n remote handling tools, n syringe shields and n protective clothing.

SHIELDING Bench top shield Vial shields Syringe shields Structural shielding

Containers for radioactive waste Several containers should be available in order to segregate the waste at the point of origin (radionuclides, half-lives, glass, paper, syringes etc.)

Equipment l relevant equipment should be purchased from authorized suppliers. Written methods should be developed with the involvement of the responsible staff (e.g. the medical physicist) and/or the RPC, for purchasing, installation, acceptance, commissioning, use, maintenance and quality control

Manufacturer/Supplier l Design facilities for likely conditions of use l Transport sources as per IAEA ST-1 l Approval test prototype devices l Provide certificate of conformity l Provide instructions for safe use and maintenance

EQUIPMENT l A nuclear medicine practice shall have a radionuclide activity calibrator and equipment for workplace monitoring. The calibration of instruments shall be traceable to a certified standards laboratory, and should be maintained by a regular quality control programme

The design of the facility should take into consideration the type of work and the radionuclides and their activities intended to be used. A safety assessment should be done in order to determine the special needs concerning ventilation, plumbing, materials used in walls, floors and work benches. Facilities

Design Objectives Safety of sources Minimize exposure of staff, patients and general public Maintain low background where most needed Fulfil requirements regarding pharmaceutical work Prevent uncontrolled spread of contamination

RADIOACTIVE CONTAMINATION BSS III.7. Registrants and licensees shall ensure that: (a) for sources for which they are responsible, measures that are optimized in accordance with the requirements of the Standards be taken as appropriate for restricting public exposure to contamination in areas accessible to the public; and (b) specific containment provisions be established for the construction and operation of a source that could cause spread of contamination in areas accessible to the public.

Reduce the risk of uncontrolled contamination l Classification of areas l Well trained staff l Documented safe procedures in the handling of radiopharmaceuticals (receipt, preparation, administration, waste disposal) l Workplace monitoring

CLASSIFICATION OF AREAS Controlled area Supervised area

Layout of a nuclear medicine department From high to low activity Controlled area

…...appropriate instructions at access points

…..display a warning symbol (in local language)

Fume hood Fume hoods shall be installed for use, as appropriate, for volatile radioactive substances. The exhaust of the fume hood shall not become a source of radiation exposure to the public.

Source Storage Source stores must: l provide protection against environmental conditions l be only for radioactive materials l provide sufficient shielding l be resistant to fire l be secure

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 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 STORAGE OF SOURCES

Segregation/Waste containers Containers to allow segregation of different types of radioactive waste should be available in areas where the waste is generated. The containers must be suitable for purpose (volume, shielding, leak proof, etc.) Glassware with radionuclides (short half- life) Syringes and needles Gloves and paper Glassware with radionuclides (medium half-life)..

A room for interim storage of radioactive waste should be available. The room should be locked, properly marked and ventilated. Each type of waste should be kept in separate containers properly labeled to supply information about the radionuclide, activity concentration etc. Flammable goods should be kept apart. Records should be kept where the origin of the waste can identified. Storage of radioactive waste

Isolation ward (iodine therapy) controlled area only one patient in the room easily cleanable surfaces and utensils extra lead shields door closed warning sign outside restrictions for visitors decontamination equipment

Isolation ward (iodine therapy) King Faisal Specialist Hospital, Riyadh