ASN Report 2017
296 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 10 - Sources of ionising radiation and their industrial, veterinary and research applications however be used under certain conditions in order to comply with the radiation protection rules applicable to workers and the public, in particular: ཛྷ ཛྷ A ban on activation of construction products, consumer goods and foodstuffs as specified by Article R. 1333-2 of the Public Health Code, by ensuring that the maximum energy of the particles emitted by the accelerators used excludes any risk of activation of the materials being verified. ཛྷ ཛྷ A ban on the use of ionising radiation on the human body for purposes other than medical. ཛྷ ཛྷ The setting up of procedures to ensure that the checks conducted on the goods or transport vehicles do not lead to accidental exposure of workers or other individuals. Thus, the use of ionising technologies to seek out illegal immigrants in transport vehicles is prohibited in France. During customs inspections of trucks using tomographic techniques, for example, the drivers must be kept away from the vehicle and other checks must be performed prior to irradiation to detect the presence of any illegal immigrants, in order to avoid unjustified exposure of persons during the inspection. 2.4 Other electrical devices emitting ionising radiation This category covers all the electrical devices emitting ionising radiation other than those mentioned above and not concerned by the license and notification exemption criteria set out in Article R. 1333-18 of the Public Health Code. This category includes, for example, devices generating ionising radiation but not used for this property, such as ion implanters, electron-beamwelding equipment, klystrons, certain lasers and certain electrical devices such as high-voltage fuse tests. 3. Manufacturers and distributors of radioactive sources ASN oversight of the suppliers of radionuclide sources or devices containing them is crucial to ensuring the radiation protection of the future users. It is based on the technical examination of the devices and sources with respect to operating safety and radiation protection conditions during future utilisation and maintenance. It also allows the tracking of source transfers and the recovery and disposal of disused or end-of-life sources. Source suppliers also play a teaching role with respect to users. At present, only the suppliers of sealed radioactive sources or devices containing them, and of unsealed radioactive sources, are regulated in France (see point 4.4). There are about 150 suppliers listed, and among them, 33 low and medium-energy cyclotrons are currently licensed under the Public Health Code in France. As at 31st December 2017, 31 cyclotrons were in operation. Among these, 18 are used exclusively for the daily production of radiopharmaceuticals, 6 are used for research purposes and 7 are used exclusively for joint production and research purposes. FUNDAMENTALS Synchrotrons The synchrotron is a member of the same family of circular particle accelerators as the cyclotron (see point 3), but is far larger, enabling energies of several gigaelectronvolts to be achieved by means of successive accelerators. Owing to the low mass of the particles (generally electrons), the acceleration created by the curvature of their trajectory in a storage ring produces an electromagnetic wave when the speeds achieved become relativistic: this is synchrotron radiation. This radiation is collected at various locations called beam lines and is used to conduct scientific experiments. FUNDAMENTALS Cyclotrons A cyclotron is a device 1.5 to 4 metres in diameter, belonging to the circular particle accelerator family. The accelerated particles are mainly protons, with energy levels of up to 70 MeV. A cyclotron consists of two circular electromagnets producing a magnetic field and between which there is an electric field, allowing the rotation of the particles and their acceleration at each revolution. The accelerated particles strike a target which is activated and produces radionuclides. Low and medium energy cyclotrons are primarily used in research and in the pharmaceutical industry to produce positron emitting isotopes, such as fluorine-18 ( 18 F) or carbon-11 ( 11 C). The radionuclides are then combined with molecules of varying complexity to form radiopharmaceuticals used in medical imaging. The best known of them is 18 F-FDG (fluorodeoxyglucose marked by fluorine-18), which is an industrially manufactured injectable drug, commonly used for early diagnosis of certain cancers. Other radiopharmaceuticals manufactured from 18 F have also been developed in recent years, such as 18 F-Choline, 18 F-Na, 18 F-DOPA, as well as radiopharmaceuticals for exploring the brain. To a lesser extent, the other positron emitters that can be manufactured with a cyclotron of an equivalent energy range to that necessary for the production of 18 F and 11 C are oxygen-15 and nitrogen-13. Their utilisation is however still limited due to their very short half-life. The levels of activities involved for the 18 F usually found in pharmaceutical facilities vary from 30 to 500 GBq per production bombardment. The positron emitting radionuclides produced for research purposes involve activities that are usually limited to a few tens of GBq.