2 ICRP Publication 103 Protection Quantities and ICRU Report 39/51 Operational Quantities

Abstract

Radiological protection requires the quantification of the exposure of the human body to ionizing radiation. To this end, the International Commission on Radiological Protection (ICRP) has developed the following protection quantities: mean absorbed dose in an organ or tissue, DT, organ/tissue equivalent dose, HT, and effective dose, E. The protection quantities are used for the implementation of dose limits and of the optimization principle. Their most recent definitions are published in the 2007 Recommendations of the ICRP (2007). The ICRP protection quantity effective dose, E, is considered to provide a single, risk-related, quantity for the control of stochastic radiation effects, valid for all persons exposed under the same conditions, independent of sex, and other individual properties of the person exposed. Internal exposure from the intake of radionuclides is also considered using effective dose. At values of an absorbed dose above a few hundreds of milligrays, tissue reactions (deterministic effects) can be of concern and absorbed doses in some tissues and organs require evaluation (Harrison et al., 2016; ICRP, 2007; 2012). ICRP (2007) sets specific limits on organ equivalent dose to prevent damage to the lens of the eye and local skin. ICRP Publication 116 (2010), published jointly with Inter national Commission on Radiation Units & Measurements (ICRU), provides sets of conversion coefficients from particle fluence to the protection quantities for an extended range of radiation types and particle energies compared with the previous joint publication (ICRP, 1996; ICRU, 1998). The conversion coefficients for the protection quantities in ICRP Publication 116 supersede the previously published values.