ASTM D2001 Test Method for Depentanization of Gasoline and Naphthas
9. Precision and Bias
9.1 The following criteria should be used for judging the acceptability of results (95 % confidence) (Note 4):
9.1.1 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 2 volume % only in one case in twenty.
9.1.2 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 4 volume % only in one case in twenty.
9.2 Bias - The quantities determined are defined by the conditions used in this empirical test method, and a statement of bias is therefore not appropriate.
NOTE 4 - Precision data are based on results obtained by five laboratories testing four samples in duplicate. The samples contained C5-and-lighter fractions covering a range of 5 to 25 volume %.
10. Keywords
10.1 depentanization; fractionations; hydrocarbon types; pentanes
