Low doses of ionising radiation: definitions and contexts

TY - JOUR

T1 - Low doses of ionising radiation

T2 - definitions and contexts

AU - Harrison, John D.

AU - Hill, Mark A.

AU - McCready-Shea, Susan

AU - Smith, Graham M.

AU - Sutton, David G.

N1 - Publisher Copyright: © 2024 The Author(s). Published on behalf of the Society for Radiological Protection by IOP Publishing Ltd.

PY - 2024/12

Y1 - 2024/12

N2 - The term ‘low dose’ is applied to different levels of dose depending on the circumstances of exposure, with the potential for confusion unless the reasoning is clear. The United Nations Scientific Committee on the Effects of Ionising Radiation has defined low absorbed doses of ionising radiation as below about 100 mGy, and low dose rates as below 0.1 mGy min−1 (6 mGy h−1). These values relate to the interpretation of scientific evidence from epidemiological and biological studies. The International Commission on Radiological Protection has used similar values of 100 mSv and 5 mSv h−1 and applied this categorisation directly to the specific situation of patients undergoing diagnostic procedures: doses below 100 mSv were referred to as ‘low’ and doses below 10 mSv as ‘very low’. Consideration of other exposure situations suggest that the same terms can be used for exposures received by emergency workers. However, for workers and members of the public in planned exposure situations, it is suggested that the term ‘low dose’ applies to doses below 10 mSv and 1 mSv, respectively—that is, below the dose limits. In each case, dose is being used as a surrogate for risk—risks at low doses are uncertain and estimates may change, but order of magnitude considerations are sufficient in most cases. Doses of < 100 mSv, < 10 mSv and < 1 mSv correspond to life-time cancer risk estimates of the order of < 10−2, < 10−3 and < 10−4, respectively.

AB - The term ‘low dose’ is applied to different levels of dose depending on the circumstances of exposure, with the potential for confusion unless the reasoning is clear. The United Nations Scientific Committee on the Effects of Ionising Radiation has defined low absorbed doses of ionising radiation as below about 100 mGy, and low dose rates as below 0.1 mGy min−1 (6 mGy h−1). These values relate to the interpretation of scientific evidence from epidemiological and biological studies. The International Commission on Radiological Protection has used similar values of 100 mSv and 5 mSv h−1 and applied this categorisation directly to the specific situation of patients undergoing diagnostic procedures: doses below 100 mSv were referred to as ‘low’ and doses below 10 mSv as ‘very low’. Consideration of other exposure situations suggest that the same terms can be used for exposures received by emergency workers. However, for workers and members of the public in planned exposure situations, it is suggested that the term ‘low dose’ applies to doses below 10 mSv and 1 mSv, respectively—that is, below the dose limits. In each case, dose is being used as a surrogate for risk—risks at low doses are uncertain and estimates may change, but order of magnitude considerations are sufficient in most cases. Doses of < 100 mSv, < 10 mSv and < 1 mSv correspond to life-time cancer risk estimates of the order of < 10−2, < 10−3 and < 10−4, respectively.

KW - exposure situations

KW - low dose

KW - low risk

UR - https://www.scopus.com/pages/publications/85207049065

U2 - 10.1088/1361-6498/ad83dd

DO - 10.1088/1361-6498/ad83dd

M3 - Article

C2 - 39374619

AN - SCOPUS:85207049065

SN - 0952-4746

VL - 44

JO - Journal of Radiological Protection

JF - Journal of Radiological Protection

IS - 4

M1 - 043003

ER -