ASTM D937 standard test method for cone penetration of petroleum
9. Report
9.1 Report the average of all results to the nearest 0.1 mm as the penetration, ASTM D937.
10. Precision and Bias
10.1 Precision - The precision of the test method as determined by statistical examination of interlaboratory results is as follows:
10.1.1 Repeatability - The difference between two test results, obtained by the same operator with the same apparatus under constant operating conditions on identical test material, would in the long run, in the normal and correct operation of the test method, exceed the following values only in one case in twenty:
2 + 5 % penetration value
10.1.2 Reproducibility - The difference between two single and independent results obtained by different operators working in different laboratories on identical test material would, in the long run, in the normal and correct operation of the test method, exceed the following values only in one case in twenty:
9 + 12 % penetration value
10.2 Bias - The procedure in this test method has no bias because the value of cone penetration can be defined only in terms of a test method.
