Radiological Protection from NORM in Industrial Processes: ICRP TG76 Working Progress

The aim of the Task Group (TG) 76 of the International Commission of Radiological Protection (ICRP) is to develop a report on protection against Naturally Occurring Radioactive Material (NORM) associated with industrial processes that may increase the radiation exposure to individuals or affect the environment. It is part of the series of reports focused on the application of ICRP general recommendations (ICRP 103, 2007) to several types of existing exposure situations. NORM is used for other than its radioactive properties otherwise it would be considered a planned exposure situation. Exposure from radon and thoron is out of the scope of the TG and should be managed separately according to the dedicated publication (ICRP 126).
NORM arises as a result of a diverse range of practices, including mining and extractive industries, production of coal, oil and gas, production and use of metals (thorium, niobium, etc.), phosphate industry, water treatment, etc. While these industries are from diverse sectors, they have common features. They are already on-going and tend to be large industries that are of economic importance. Most of them are subject to authorization due to associated risks from multiple hazards, radiological risk is rarely dominant and the radiological protection (RP) culture is often poor. Doses are variable and may be higher than in nuclear industry, but they are capped because there is almost no real prospect of emergency exposure situations occurring.
With the culture of risk management being largely focused on non-radiological hazards, there is a need to introduce greater RP to these industries, within an integrated (multi-hazard) and graded (commensurate with risk) approach. NORM falls within the category of existing exposure situations. The source already exists, it is not deliberately introduced in an industrial process for its radioactive properties and the exposures generated are incidental.
For the protection of workers, while it is not so easy to determine whether they should be considered as occupationally exposed, each workplace should be managed properly within a graded approach according to the dose level and the selection and implementation of protective actions. Two bands of dose are recommended for the selection of the Reference Level (RL): below a few mSv/y (most cases) and from a few mSv/y to 20 mSv/y. Two series of protective actions are proposed. The first relates to workplaces and working conditions, the second is focused on each worker individually. The way to implement protective actions may be more or less thorough according to the situation.
For the protection of the public, the starting point is characterization of the situation (who is exposed, when, where and how). A RL should be set (in the lower range of the band 1-20 mSv/y) and any required actions for public protection should be justified and optimized, with stakeholder engagement. Practically, the protection of the public is ensured through the controls of discharges and waste arising or the reuse of residues notably in building materials.
For protection of the environment it is recommended that radiological risk is included within environmental impact assessments. This would involve radiological characterization and the analysis of exposure pathways and the transfer of radiological materials within the environment. Doses to non-human species should be calculated and potential effects evaluated against dosimetric criteria. Stakeholders should again be involved in the process.
A public consultation on the draft TG 76 report is expected in 2018, with the final report being published by the end of 2018