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Radiation protection and environmental standards

Measurements for radiation protection dosimetry in medicine, industry, science and in the environment require instruments for photon, beta and neutron radiation and for combinations of them. To characterize and calibrate such instruments reference radiation fields are required, together with the dosimetry of these fields and the methods to calibrate the instruments. For all these tasks standards are available; an overview of them is given in this paper. In addition, an overview of secondary standard instruments is provided which serve as a tool to ensure the traceability between the primary standards laboratories and the calibrating and type testing laboratories. The part on neutrons is kept short as neutrons will be dealt with in a future special issue in this journal. About 10 years ago, Böhm et al (1999 Radiat. Prot. Dosim. 86 87–105) summarized the ISO recommended reference radiations used in radiation protection. This paper updates that review and adds environmental radiation and secondary standard instruments.