Energy response of LiF:Mg, Ti dosemeters to ISO 4037 and typical diagnostic x-ray beams in Tanzania.
The energy response of three types of LiF:Mg, Ti dosemeter to standard x-ray calibration qualities and diagnostic x-rays has been studied. The aim of this study was to investigate whether the inherent mismatch between these qualities compromises the accuracy of the evaluated occupational doses in diagnostic x-ray facilities. A sample of 10 dosemeters of each type was exposed to air kerma of 5 mGy from each of six ISO 4037 (series 407) x-ray radiation protection calibration qualities (2.7 mm Al to 2.45 mm Cu HVL (half-value layer)) and 11 diagnostic x-ray qualities (1.45-4.9 mm Al HVL). The results show that the TLD energy response to ISO 4037 and diagnostic x-rays as normalised to 137Cs ranged from 1.1 to 1.44 and 0.57 to 1.54 respectively. This implies an energy response range from -52 to +7% for diagnostic x-rays relative to ISO 4037 x-rays, hence a maximum over-response of 52%. Despite this discrepancy, the results show that the mismatch between calibration and diagnostic x-ray beams does not significantly compromise the accuracy of individual doses in diagnostic x-ray facilities.
Muhogora
W E
WE
National Calibration Laboratory for Ionizing Radiation, Arusha, Tanzania. wmuhogora@yahoo.com
Ngoye
W N
WN
Lema
U S
US
Mwalongo
D
D
D005459:Fluorides; D006801:Humans; D018020:Lithium Compounds; D008274:Magnesium; D016273:Occupational Exposure; D011835:Radiation Protection / Q000592:standards*; D013636:Tanzania; D013819:Thermoluminescent Dosimetry / Q000295:instrumentation*; D014025:Titanium; D014965:X-Rays
D018020:Lithium Compounds; C027651:lithium fluoride; D014025:Titanium; D008274:Magnesium; D005459:Fluorides