Naturally occurring radioactive material which is not processed for its radioactive, fertile or fissile properties (NORM)
Employers who work with materials that contain small but, from a radiation protection perspective, significant amounts of naturally occurring radioactive substances are required, under the Ionizing Radiations Regulations 2017 (IRR17), to take action to restrict radiation exposure of their employees and other persons who may be affected by their work with such materials.
Some processes with a recognized potential to cause significant radiation exposure occur in the oil and gas industry where naturally occurring radium and its daughters, may build up over time as scale in pipes and vessels. Some metal smelting applications may also cause exposure to NORM; here naturally occurring radionuclides may concentrate in foundry slag or may be present in radiologically significant concentrations in refractory sands which contain low concentrations of natural uranium and thorium. Exposure arising from work with materials that contain NORM, can sometimes come directly from the raw materials themselves, but more commonly results from their processing. IRR17 applies where such processes involve naturally occurring radioactive radionuclides which are not processed for their radioactive, fertile or fissile properties and are above the activity levels and concentrations set out in Schedule 7, Part 2 of IRR17. Employers must determine in the health and safety risk assessment, required by the Management of Health and Safety at Work Regulations 1999, whether such processes involve naturally occurring radioactive radionuclides above these levels and, if so, take the necessary steps to comply with IRR17.