Basic Ionization Dosimetry for Radiological Protection Management

Abstract

F Scarlat, E Stancu, A Scarisoreanu

Management of exposure to ionizing radiation based on the three principles of radiological protection (justification, optimization, and dose limits) requires precision and accuracy of the entire dosimetry chain starting with the absorbed dose and ending with the effective dose. Approved absorbed dose limits below about 100 mSvper five years are important to prevent the induction of stochastic effects.In this sense, the paper reviews the basics of exposure to external and internal radiation using ionization dosimetry. After presenting the characteristics of ionizing radiation, radiometric quantities (Φ, , Ψ,Ψ) and dose constants (ΓX, ΓK, ΓD), the paper presents, first, the basic dosimetry quantities (X, K, D), the factors calibration coefficients (NX, NK, ND,), photon interaction coefficients (µ/ρ, µtr /ρ, µab /ρ), electron interaction coefficients (Scol , Srad , L).Continue with the quantities of radiological protection valid for external and internal radiation exposure (DTR, HT , E), based on the quality factor and the radiation and tissues weighting factors(Q, wR, wT), which in turn are based on RBE and the risk coefficients(Ra,Rr,s),to prevention of stochastic effects. Next, the quantities of protection for external exposure, operational quantities of area (H * (10), H ‘(d, Ω)) and individual monitoring (HP (10), HP (d)), quantities of radiological protection for internal exposure, in the MIRD methodology, (D= AS S(rS ←rT)) and in the ICRP methodology, (HT (50), E (50)) based on the nuclear decay law. Derived quantities for internal exposure control (ALI, DAC), Radon exposure to air (WL, WLM) and dose limits are shown. The paper concludes with the formula for the annual effective dose,E(mSv) =HP (10) + E (50) +Esub(DAC) +E(mSv←WLM), for workers and members of the public.

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