National patient dose measurement protocols: an investigation on behalf of ICRU

Countries that measure radiation exposure of patients during diagnostic radiology generally adopt more than one measurement system. The common methods require the measurement of the primary beam air kerma or absorbed dose in air, or of entrance surface absorbed dose using thermoluminescence dosimetry (TLD). Less common is the direct measurement of the product of absorbed dose in air and the area of the patient exposed during a dose area product meter (DAP). In each case, organ absorbed doses and whole-body effective dose equivalent may be calculated. Under the auspices of the ICRU, an initial investigation has been made of which methods of measurement and calibration are used in various countries and whether there is a national approach. The survey was conducted to identify the feasibility of a common approach with internationally agreed recommendations on quantities to be measured and calibrations to be used. (Author)