Packages containing enriched, and therefore fissile UF6, are also subject to the prescriptions previously presented (see point 2.3.3). The UF6 is transported in type 48Y or 30B metal cylinders. In the case of enriched UF6, this cylinder is transported within a protective shell, which provides the necessary protection for withstanding the tests applicable to packages containing fissile materials. The package models containing UF6 must also be approved by ASN or a competent foreign authority, before they can be allowed to travel. 2.3.5 Type C packages Type C packages are designed for the transport of highly radioactive substances by air. In France there are no approved type C packages for civil uses. 2.4 THE REQUIREMENTS GUARANTEEING THE RELIABILITY OF THE TRANSPORT OPERATIONS 2.4.1 Radiation protection of workers and the public The radiation protection of workers and the public during shipments of radioactive substances must be a constant concern. The public and non-specialist workers must not be exposed to a dose greater than 1 millisievert per year (mSv/year). However, this limit is not intended to be an authorisation to expose the public to up to 1 millisievert (mSv). Moreover, the justification and optimisation principles applicable to all nuclear activities also apply to the transport of radioactive substances (see chapter 2). Radiation protection is the subject of specific requirements in the regulations applicable to the transport of radioactive substances. Thus, for transport by road, the regulations stipulate that the dose rate at the surface of the package must not exceed 2 millisieverts per hour (mSv/h). This limit may be raised to 10 mSv/h in “exclusive use”(1) conditions, because the consignor or consignee can then issue instructions to restrict activities in the vicinity of the package. In any case, the dose rate must not exceed 2 mSv/h in contact with the vehicle and must be less than 0.1 mSv/h at a distance of 2 metres from the vehicle. Assuming that radiation at the surface of a transport vehicle reaches the limit of 0.1 mSv/h at 2 metres, a person would have to spend 10 consecutive hours at a distance of 2 metres from the vehicle for the dose received to reach the annual public exposure limit. These limits are supplemented by requirements relative to the organisation of radiation protection within companies. The companies working in transport operations are required to implement a radiological protection programme, comprising the steps taken to protect the workers and the public from the risks arising from ionising radiation. This programme is more specifically based on a forecast evaluation of the doses to which the workers and the public are exposed. According to the results of this evaluation, optimisation measures must be taken to ensure that these doses are As Low As Reasonably Achievable (ALARA(2) principle): for example, lead-lined trolleys could be made available to handling staff to reduce their exposure. This evaluation also makes it possible to decide on whether to implement dosimetry to measure the dose received by the workers, if it is anticipated that it could exceed 1 mSv/year. Finally, all the transport players must be trained in the risks linked to radiation, so that they are conscious of the nature of the risks, as well as how to protect themselves and how to protect others. 1. Exclusive use corresponds to cases in which the vehicle is used by a single consignor. This consignor may then give specific instructions for all the transport operations. 2. The ALARA (As Low As Reasonably Achievable) principle appeared for the first time in Publication 26 from the International Commission on Radiological Protection (ICRP) in 1977. It was the result of a process of reflection on the principle of optimising radiological protection. The workers involved in the transport of radioactive substances are also subject to the provisions of the Labour Code concerning protection against ionising radiation. ASN has updated Guide No. 29 to help carriers meet their regulatory obligations relative to the radiation protection of workers and the general public. This update aims to take account of the new provisions introduced by Directive 2013/59/Euratom, known as the “BSS Directive”, notably the periodic check that vehicles used to carry radioactive substances are contamination free. 2.4.2 Package and vehicle marking So that the workers can be informed of the level of risk arising from each package and so that they can protect themselves effectively, the regulations require that the packages be labelled. There are three types of labels, corresponding to different dose rate levels in contact and at 1 metre from the package. The workers operating close to the package thus have a visual means of knowing which packages entail the highest dose rates, and can thus limit the time they spend close to them and can put them as far away as possible (for example by loading them towards the rear of the vehicle). The packages containing fissile materials must also display a special label. This is to ensure that these packages are kept apart to prevent the triggering of a nuclear chain reaction. The special label enables compliance with this prescription to be easily verified. Finally, the markings on packages must comprise their type, the address of the consignor or consignee and an identification number. This enables delivery errors to be avoided and allows packages to be identified if lost. The vehicles carrying packages of radioactive substances must also have specific markings. Like all vehicles carrying dangerous goods, they carry an orange-coloured plate at the front and back. They must also carry a placard with the radiation trefoil and the word “Radioactive”. The purpose of these vehicle markings is to provide the emergency services with the necessary information in the event of an accident. 2.4.3 Responsibilities of the various transport players The regulations define the responsibilities of the various parties involved during the lifetime of a package, from its design up to the actual shipment. These responsibilities entail special requirements. Therefore: ∙ The package model designer shall have designed and sized the packaging in accordance with the intended conditions of use and the regulations. It must obtain an ASN certificate (or in certain cases a certificate from a foreign authority) for type B or fissile packages containing UF6. ∙ The manufacturer must produce packaging in accordance with the description given by the package designer. ∙ The consignor is responsible for providing the carrier with a package complying with the requirements of the regulations. It must in particular ensure that the substance is authorised for transport, verify that the package is appropriate for its content, use a package that is approved (if necessary) and in good condition, carry out dose rate and contamination measurements and label the package. ∙ Transport may be organised by the forwarding agent. They are responsible, on behalf of the consignor or the consignee, 276 ASN Report on the state of nuclear safety and radiation protection in France in 2023 • 09 • Transport of radioactive substances
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