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The study of actual radiation exposures encountered by workers involved in the transport of minerals and mineral concentrates containing naturally-occurring radioactive materials has been undertaken over a four-year period,between 2008 and 2012.Hundreds of measurements were made in the process of transport of NORM between mining and processing sites in Australia (road,rail and marine transport); numerous measurements were also made at and between the ports in Australia,Peoples Republic of China and Japan.The main subject of the study was thorium and uranium containing minerals and mineral concentrates (such as ilmenite,rutile,zircon,monazite and other minerals) and the study was carried out in three stages: The first one was mostly concentrated on measurements in Australia and was jointly sponsored by the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA),mineral sands industry and Calytrix Consulting; The second stage was focussed on obtaining more data from Australian and international transport routes and was jointly sponsored by the mineral sands industry and Calytrix Consulting; During the third stage additional monitoring was undertaken addressing materials shipped from Australia in bulk and in containers to overseas ports and was done solely by Calytrix Consulting.It has been found that - The use of the exclusion factor of 10 for the concentrations of radionuclides in natural materials in the IAEA Transport Safety regulations is appropriate and should be maintained;.The dose rates from all potential pathways of exposure of workers can be accurately predicted,based on the concentrations of thorium and uranium in the transported material; and.These dose rates remain the same irrelevant of the mode of transport - road,rail or marine.The information presented in the paper allows,by the use of simple charts,to accurately predict potential doses to workers involved in transport of NORM.It is suggested that it can be used in any assessments of potential exposures of workers that may be required prior to the commencement of the NORM transport process - by both regulatory bodies and by the mining and mineral processing industry.