Comparison of Excitation Sources for Portable XRF Devices Relative to Operator Dose Considerations
T. Hazlett, D. Eames, J. Hazlett, D. Dunn
X-ray fluorescence (XRF) has become a standard technique for elemental detection and measurement, particularly in applications such as lead in paint analysis. Many hand held instruments in use today use Co-57 as the excitation source for this technique. These instruments are compact, accurate, and easy to use. As with all such devices, however, protection of the operator from radiation exposure is a prime concern, and minimization of that exposure is a key design consideration. This paper explores the use of an alternate excitation source, Gd-153, for portable XRF instruments, particularly as it pertains to health physics issues. Transmitted radiation measurements for both Gd-153 and Co-57 are taken through various thicknesses of shielding and compared. Also reported is the contribution of backscattered radiation to total operator dose for both isotopes. The data illustrates the advantages of using Gd-153 in portable XRF devices in terms of dose and as low as reasonably achievable (ALARA) considerations.
This abstract was presented at the 33rd Annual Midyear Meeting, "Instrumentation, Measurements, and Electronic Dosimetry", Poster Session, 1/30/2000 - 2/2/2000, held in Virginia Beach, VA.