REPORT
ects currently under study: a compilation of best decay scheme data, a user's guide to radioactivity standards and measurements, and a uniform standard certificate to accompany all standards. Kahn explained that the compilers of the best decay scheme data would attempt to choose from among conflicting gamma branching, beta branching, half-life, and similar nuclear data those values which appear most reliable. Only a best value for each parameter will be published; thus, consistency will prevail even while accuracy is being further sought. The need for such a compilation has been apparent for some time. At the NRC subcommittee meeting each member had been assigned a number of the most used radioisotopes, and each is to investigate the literature and decide which data seem most valid. The user's guide is to supplement other publications in the field, rather than to supplant them. As proposed by the group, the guide would discuss basic techniques and precautions to be observed in the use of radioactivity standards. Kahn urged the audience to submit any suggestions to the subcommittee for material or subjects to be included in this guide. A number of suggestions and points of technique were engendered through discussion at the panel session; some of these are mentioned in this report. "The need for a standard certificate," Kahn said, "has been evident for a long time. The subcommittee is working on one which will provide most of the useful information. Naturally, no one could prepare a standard certificate which would include everything that anybody might possibly want to know, but it is hoped there will be enough information in such a certificate to be useful." This information includes chemical and physical description of the standard, purity, method of production of the radionuclide, method of standardization, statement of errors, estimated inaccuracy as a function of elapsed time since standardization and best decay scheme data. G. I. Gleason, who as Chief Chemist at Abbott Laboratories' Oak Ridge facility has responsibilities as both user and distributor of
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Circle No. 16 on Readers' Service Card VOL.
36, NO. 2, FEBRUARY 1964
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