               TREATMENT OF EXTREME VALUES (OUTLIERS)
                    (Modification of ASTM E-178)


If a group of measurements include a very large, or a very small value which
appears to be outside the normal limits of variation, proceed as follows to
determine if the value should be discarded.

1.   Tabulate the test results, add to obtain the sum, and divide this sum by
     the number of test results to obtain the Mean or Lot Average.

2.   Obtain the difference between each test result and the Mean, Square each
     difference and add the results to obtain the sum of the square of the
     differences.

3.   Divide the sum of the squares of the differences by the number of
     measurements less one.

4.   Find the square root of the value obtained in Step 3 above.  This gives
     the Standard Deviation for the Lot.

5.   Divide the difference between the Mean obtained in Step 1 above and the
     test result in question by the Standard Deviator obtained in Step 4
     above.  This gives the T value.

6.   If the T value (disregarding algebraic sign) obtained in Step 5 above
     exceeds the Critical T Value listed below and no assignable cause can be
     determined for the test result in question, discard this test result.

     Number of Observations, N               Critical T Value
               3                                  1.15
               4                                  1.48
               5                                  1.71
               6                                  1.89
               7                                  2.02
               8                                  2.13
