Abstract：
:Dose measurements following 10 min irradiations with a portable x-ray fluorescence spectrometer composed of a miniature x-ray tube and a silicon PiN diode detector were performed using thermoluminescent dosimeters consisting of LiF:Mg,Ti chips of 3 mm diameter and 0.4 mm thickness. The table-top setup of the spectrometer was used for all measurements. The setup included a stainless steel lid which served as a radiation shield. Two rectangular polyethylene skin/soft tissue phantoms with two cylindrical plaster of Paris bone phantoms were used to study the effect of x-ray beam attenuation and backscatter on the measured dose. Eight different irradiation experiments were performed. The average dose rate values measured with TLD chips within a 1 x 1 cm(2) area were between 4.8 and 12.8 mGy min(-1). The equivalent dose for a 1 x 1 cm(2) skin area was estimated to be 13.2 mSv. The maximum measured dose rate values with a single TLD chip were between 7.5 and 25.1 mGy min(-1). The effective dose corresponding to a proposed arsenic/selenium skin measurement was estimated to be 0.13 microSv for a 2 min irradiation.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Gherase MR,Mader JE,Fleming DEdoi
10.1088/0031-9155/55/18/015subject
Has Abstractpub_date
2010-09-21 00:00:00pages
5499-514issue
18eissn
0031-9155issn
1361-6560pii
S0031-9155(10)54716-Xjournal_volume
55pub_type
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