12.1 The precision of this test method as obtained by statistical examination of interlaboratory test results is as follows:
12.1.1 Repeatability - The difference between successive tests 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:
12.1.2 Reproducibility - The difference between two single and independent results obtained by different operators 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:
12.2 Bias - The bias of this test method cannot be determined since an appropriate standard reference material containing a known level of ash in liquid petroleum hydrocarbon is not available.
13. Keywords
13.1 ash; crude oils; distillate oils; fuel oils; lubricating oils