04 July 2022

Calculating exposure from naturally occurring radioactive material (NORM) has been standardised by the Australian Radiation Protection and Nuclear Safety Agency to encourage national uniformity and ongoing alignment with international best practice. 

ARPANSA has updated their published dose conversion factors for occupational exposure to radionuclides. These factors are used to calculate how much ionising radiation exposure someone receives from intakes of natural radioactive elements like uranium.  

The update will benefit workers employed in the mining and resources sector and ensure dose is calculated in the same way in each State and Territory.  

ARPANSA Chief Radiation Health Scientist Dr Rick Tinker says that the improved guide will help industry with their radiation management plans.  

‘We are confident that the new conversion factors better reflect the actual dose from radionuclides exposure,' Dr Tinker said. 

‘This is particularly useful for workers in industries where naturally occurring radioactive material is present.'

Average radiation exposure in Australian NORM industries are well below the occupational exposure limit, which is 20 mSv per year averaged over 5 years.  

‘Despite generally low exposures, NORM is an occupational hazard that requires ongoing control,' said Dr Tinker.  

‘Updating the dose conversion factors ensures calculated doses are as accurate as possible.’ 

Average background radiation exposure in Australia is 1.7 mSv per year from natural sources and currently Australians are exposed to an average of 1.7 mSv per year from medical exposures. 

No health effects have been observed or are expected to be observed at the very low doses normally received in these occupations.  

You can view the amended conversion factors and associated guidance here.  

Access to information FOI disclosure log Information public scheme