A Documentary History of the United States¶ First Plutonium Isotopic Reference Materials

The New Brunswick Laboratory (NBL) was founded in 1949 by the U.S. Atomic Energy Commission to assist in the development of uranium (and in 1959 plutonium) analytical measurement methods. Over the years, the laboratory developed expertise and analytical methods relating to many aspects of the nuclear fuel cycle and weapons materials. The National Bureau of Standards (re-QDPHG??1,67????VHUYHG????DV??1,67??VWLOO??VHUYHV????DV??WKH??QDWLRQ¶V??VRXUFH??IRU??6WDQGDUG?? Reference Materials (SRMs) and is the certifying authority and the national metrology institute for WKH??8QLWHG??6WDWHV??????%HJLQQLQJ??LQ??WKH??HDUO\\??????????¶V????WKH??QHHG??IRU??XUDQLXP??DQG??WKHQ??SOXWRQLXP??SULPDU\\?? reference materials became apparent. NBS, NBL and various AEC laboratories collaborated on identifying reference materials needs, procuring base materials, developing the necessary chemical and handling techniques, studying chemical forms for suitability and storage as reference materials, and certifying the chemical and physical properties of the produced SRMs. Beginning in 1956, there were a series of communications between the AEC and NBS identifying nuclear reference materials needs and priorities, including a plutonium isotopic standard. The first plutonium isotopic standard produced was SRM 948, which was of weapons-grade isotopic composition. As FRPPHUFLDO??UHDFWRUV??DQG??IXHO??UHSURFHVVLQJ??GHYHORSHG??WKURXJK??WKH??HDUO\\??????????¶V????WKH??QHHG??IRU??WZR?? new isotopic materials containing higher amounts of 240Pu became apparent. This need lead to the certification of SRMs 946 and 947. This report compiles the information and data regarding the production and certification of the three plutonium isotopic reference materials, and discusses plans for the future of these and other materials.