This test method is applicable to samples containing 2 to 10 % gadolinium oxide and 90 to 98 % uranium oxide on the “as received” basis. The method may be used to determine concentration of either uranium, gadolinium, or both.

Either wavelength-dispersive or energy-dispersive X-ray fluorescence systems may be used provided the software accompanying the system is able to accommodate the use of internal standards.

1.1 This test method describes the steps necessary for the preparation and analysis by X-ray fluorescence (XRF) of gadolinium or uranium (or both) in gadolinium oxide-uranium oxide pellets or powders.

1.2 This test method requires the use of appropriate internal standard(s). Care must be taken to ascertain that samples analyzed by this method do not contain the internal standard element(s) or that this contamination has been corrected for mathematically whenever present. Such corrections are not addressed in this test method.

1.3 This standard contains notes that are explanatory and are not part of the mandatory requirements of the standard.

1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautions are given in Section 8 and various notes throughout the method.