Characteristic analysis for dose area product meter and conversion to air kerma

Among the basic characteristics of the dose area product meter, the following were examined: effect of the heel effect which derives from hardening, atmospheric correction coefficient, response of measuring plane of the DAP meter, target focus angle of an x-ray tube assembly of quality of radiation by the area dosimeter mounting, and conversion from the value of the area dosage of air kerma. In terms of tube voltage, the IEC standard is almost always observed, if the radiation field in the dosimeter's surface area is within 6 cm x 6 cm. Error was 17.6%, even if all factors were not considered, and even if the conversion to air kerma was possible. It was indicated that the conversion to air kerma in the patient was possible when the radiation field and measurement error in the dosimeter's surface were considered. (author)