• An Interim Progress Report on Stages 1 and 2 of the International Collaborative Program

      Scott, E. M.; Aitchison, T. C.; Harkness, D. D.; Baxter, M. S.; Cook, G. T. (Department of Geosciences, The University of Arizona, 1989-01-01)
      We report in this paper on a preliminary analysis of Stages 1 and 2 of the International Collaborative program. We have chosen to concentrate on the internal and external consistencies of the participating laboratories. The two stages so far completed have dealt only with the processes of sample synthesis and counting, and results indicate that the major component of variability lies in the counting process. Outlying laboratories are observed at each stage. A third stage is in progress which will allow an assessment of any further variability due to sample pretreatment. With the inclusion of duplicate samples in each stage, we are able to report that laboratories are remarkably consistent internally, ie, the differences between duplicates generally agree with the laboratory's claimed precision.
    • Design and Preparation of Samples for the International Collaborative Study

      Harkness, D. D.; Cook, G. T.; Miller, B. F.; Scott, E. M.; Baxter, M. S. (Department of Geosciences, The University of Arizona, 1989-01-01)
      Sample materials issued to participants in the interlaboratory calibration exercise are defined and in context of their intended interpretational significance. Preparation of the benzene and calcium carbonate standards as issued for stage 1 is described in detail; likewise, the source and pretreatment/extraction of the environmental samples dispatched for stages 2 and 3.