use. These badges are evaluated each quarter to check for 
personal radiation exposure. In addition, in accordance with 
New York State regulations, the instrument is leak-tested 
every six months. 
6.5 Maintaining Equipment 
Day-to-day maintenance of the XRF is generally not difficult 
or costly. Operators should clean the instrument s display 
window with cotton swabs, clean the case with a soft cloth, 
and charge the batteries as directed in the owner s manual. 
Beyond that, operators usually just need to take care not to 
drop the instrument, get it wet, or neglect the calibration 
checks recommended by the manufacturer. 
Over the long term, however, XRF owners face the very sig¬ 
nificant maintenance concern of replacing the instrument s 
radioactive source. All radioactive isotopes decay at a fixed 
rate. The half-life of 109 Cd (cadmium-109), for example, is 
about 15 months. After that, the XRF can still be used, but 
the instrument becomes progressively less efficient. Readings 
that once took 30 to 60 seconds take progressively longer. 
Eventually the wait becomes burdensome, and the isotope 
must be replaced. Syracuse sends its instrument back to the 
manufacturer, which disposes of the spent radioactive source, 
installs the new source, upgrades the instrument s software, 
and provides whatever preventive maintenance is needed. See Chapter 7, Section 7.3 for more 
information on managing and disposing of hazardous wastes generated in a lead dust monitor¬ 
ing and mitigation program. 
6.6 Resources for Additional Information 
XRF Accuracy 
U.S. EPA, Office of Research and Development, Environmental Technology Verification 
Report on Field Portable X-ray Fluorescence Analyzer, Niton XL Spectrum Analyzer, March 
1998, EPA/600/R-97/150. Visit www.epa.gov/etv/verifications/vcenterl-22.html. 
Midwest Research Institute, XRF Performance Characteristic Sheet, Edition Number 4, Niton 
XL 309, 701-A, 702-A, and 703-A Spectrum Analyzers, April 17, 1998, in accordance with 
EPA Methodology for XRF Performance Characteristic Sheets, September 1997, EPA 747-R- 
95-008. Copies can be obtained from the National Lead Clearinghouse at 1-800-424-LEAD. 
Clark, Scott, William Menrath, Mei Chen, Sandy Roda, and Paul Succop. Use of a Field 
Portable X-Ray Fluorescence Analyzer to Determine the Concentration of Lead and Other 
Metals in Soil and Dust Samples. To order, contact the University of Cincinnati Department of 
Environmental Health at 513 558-1749. 
4 B 
Chapter 6 
