Mixed Analyte Performance Evaluation Program
                          Statistical Summary

Sample Id:  MAPEP-95-S2
           Number Labs Sample   Grand     Grand       Mean %    Range    Range
Analyte     Reporting   Size     Mean     Std Dev     Bias      Min       Max
Aluminum      39         36   14362.2   1673.40      12.25   11635.3   17636.7
Arsenic       36         29      6.48      0.62      12.06      4.73      7.70
Barium        40         39    239.81     24.19       7.45    195.67    293.00
Cadmium       39         35      7.79      0.76       8.72      6.13      9.01
Calcium       39         39   31344.9   1701.95       4.80   24600.0   35815.3
Chromium      39         36     35.57      2.87      15.77     30.23     51.80
Cobalt        37         37      6.06      0.86      12.56      4.95      8.17
Copper        37         36     79.91      5.49      10.16     68.73     91.77
Iron          38         38   18585.6   2167.57       8.84   14133.3   23452.3
Lead          39         39    279.18     11.97       3.81    238.00    329.90
Magnesium     38         38   6511.73    537.14       7.18   5691.67   8208.33
Manganese     38         37    289.74     30.69       6.30    217.00    341.33
Nickel        38         36     19.67      2.17      11.74     16.93     24.63
Potassium     37         28   4093.19    832.37      16.54   3250.00   5636.67
Silver(1)     31         31      0.49      0.09      16.51      0.37      0.65
Sodium        37         34   1260.75    149.75      10.29    970.00   1603.33
Vanadium      38         33     39.86      5.21       9.68     32.00     53.04
Zinc          38         38    782.78     40.12       7.01    704.43    871.67
Americium-241 36         34      7.74      1.01       9.73      5.77      9.83
Cesium-137    45         42   2658.40    203.83       8.32   2168.67   3120.00
Cobalt-60     45         43    256.41     23.32       8.46    202.33    321.33
Plutonium-238 35         23      5.29      0.81      12.31      4.19      7.02
Plutonium-239 39         33      5.28      0.77      12.15      4.09      6.54
Strontium-90  29         23    173.23     25.85      13.49    140.00    228.78

NOTE:  1) The variability of the silver results in study 95S2 exceeded
        'typical' confidence intervals and thus has been eliminated from
        the study.  All laboratories that reported silver results will be
        'acceptable'.

       2) The results present in this summary table DO NOT reflect those 			
        laboratories which performed TOTAL inorganic metals by fusion or
        neutron activation.

        Sample size excludes outliers.
        Outliers are defined as laboratory means with a bias greater than 
        30 percent.  Range minimum and maximum values refer to the laboratory
        means.

11/20/96                               Page 1