During uranium mining and processing, workers may be internally exposed from inhalation of radon progeny, inhalation of aerosols containing long lived alpha activity, and exposed externally to gamma rays emitted from the ores, process materials, products and tailings. World annual uranium production in 2015 was nearly 55 975 tU (Uranium 2016: Resources, Production and Demand - A Joint Report by the Nuclear Energy Agency and the International Atomic Energy Agency). With the current interest in nuclear power, there has been an increase in uranium exploration and also in the development of new uranium mining and processing facilities in many countries. As a consequence, the numbers of workers in uranium mining and processing may increase substantially within a few years. With this in mind, the International Atomic Energy Agency (IAEA) has proposed the development of an information exchange system for occupational exposure in the uranium mining and processing industry with the view to strengthen occupational radiation protection arrangements for workers, to share dose reduction information, operational experience and information to improve the optimization of worker doses, and to support quality assurance programs across the industry. The information will also support the development of safety standards for uranium industry.
To support this broad objective, the following key activities have been identified:
Occupational exposure is the exposure of workers incurred in the course of their work. The current focus is on occupational exposures associated with the operation of a mine or processing facility. At a later stage of the project this could be expanded to all life cycle activities from exploration to closure and surveillance.
The dosimetric information requested is by exposure pathway – external gamma, inhalation of aerosols containing long lived alpha activity and radon and its progeny as well as the total effective dose. Provision is also made for dose data and supporting information to be made available by workgroup.
It is understood that monitoring practice and the dose assessment procedures and assumptions used to estimate worker doses vary from operation to operation and by jurisdiction. Doses can be assessed, for example, from area monitoring and estimates of occupancy times, and/or based directly on individual dose measurements. The procedures and assumptions for dose assessment will affect not only the estimation of dose by pathway but also total dose. Thus, it is important to document any assumptions made in estimating and reporting dose and values of key parameters. An example might be the use of personal protective equipment such as respirators and the protection factor assumed for their use.
There is a variety of potential uses of an information system for uranium miners' dosimetric data. The demands on developing and maintaining such an information system are proportionately large. Thus, it is important to develop the information system in a structured manner that supports the objectives and can be supported by available resources, but allows for expansion of the data base in future.
It is envisaged that the request for data will be made to a single point of contact in the lead authority in each Member State. The lead authority will also work with the national dose registry in each country to provide suitable aggregated data. Moreover, dependent on country, the lead authority may forward these requests directly to operators of individual facilities.
A draft questionnaire was provided to the main uranium producing Member States and responses received through official channels.
There are several potential users of the information in this system, including; regulators in uranium producing and new-comer countries, the IAEA and national authorities in the Member States to support various initiatives for the development of leading practices, the IAEA to support the development of safety standards in uranium mining and processing, the UNSCEAR to support their periodic evaluations of levels of dose (by exposure pathway) and trends in dose by country, types of operation and workgroup, mining industry with established mining operations to support optimization of protection, quality assurance efforts, improving occupational dose assessment, exchange of information, while developing new projects, especially in developing countries to establish performance objectives and radiation protection programmes and the industry and professional associations in optimising work safety programmes and evaluating the implications of change in regulations.