ASTM D5984 Test Method for Semi-Quantitative Field Test Method for Base Number
ASTM D5984 Standard Test Method for Semi-Quantitative Field Test Method for Base Number in New and Used Lubricants by Color-Indicator Titration
9. Precision and Bias
9.1 The precision of this test method as determined by the statistical examination of test results from 11 samples of new and used oils, covering base numbers between 0 and 20, run in duplicate by nine different laboratories (Research Report D02-1345) is as follows:
9.1.1 Repeatability - The difference between successive 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 value only in one case in twenty:
r = 0.94 base number units (mg KOH/g sample)
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 the following values only in one case in twenty:
R = 1.91 base number units (mgKOH/g sample)
9.2 Bias - This procedure has no bias because the base number can be defined only in terms of the test method.
10. Keywords
10.1 base number; color-indicator titration; lubricants; test kit
