Factors governing selection of a method for the determination of plutonium include available quantity of sample, sample purity, desired level of reliability, and equipment.

4.1.1 This test method determines 5 to 10 mg of plutonium with prior dissolution using Practice C 1168.

4.1.2 This test method calculates plutonium assay using physical constants as reference standards.

4.1.3 Chemical standards are used for quality control when prior chemical separation of plutonium is necessary to remove interferences (9).

Committee C-26 Safeguards Statement⁴ :

4.2.1 The materials (plutonium metal, plutonium oxide or mixed oxide [(U, Pu) O₂] powders and pellets) to which this test method applies are subject to nuclear safeguards regulations governing their possession and use. Materials for use by the commercial nuclear community must also meet compositional specifications.

4.2.2 The analytical method in this test method both meets U. S. Department of Energy guidelines for acceptability of a measurement method for generation of safeguards accountability measurement data and also provides data that may be used to demonstrate specification compliance in buyer-seller interactions.

1.1 This test method describes the determination of plutonium in solutions of unirradiated nuclear-grade (that is, high-purity) materials by controlled-potential coulometry. Controlled-potential coulometry may be performed in a choice of supporting electrolytes, such as 0.9 M HNO3, 1 M HClO 4, 1 M HCl, 5 M HCl, and 0.5 M H2SO4. Limitations on the use of selected supporting electrolytes are discussed in Section 5. Optimum quantities of plutonium for this procedure are 5 to 10 mg.

1.2 Plutonium-bearing materials are radioactive and toxic. Adequate laboratory facilities, such as gloved boxes, fume hoods, controlled ventilation, etc., along with safe techniques must be used in handling specimens containing these materials.

1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

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.