10. Calculation
10.1 By use of the calibration curve, convert the net absorbance obtained to milligrams per kilograms of p-tertiary-butylcatechol.
11. Precision and Bias
11.1 Precision - The precision of this test method as obtained by statistical examination of interlaboratory test results is as follows:
11.2 Repeatability - The difference between successive 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 one case in twenty:
11.3 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 one case in twenty:
11.4 Bias - Since there is no accepted reference material suitable for determining the bias for the procedure in this test method for measuring TBC in hydrocarbons, no statement on bias is being made.
12. Keywords
12.1 light hydrocarbons; oxidation inhibitor; p-tertiary butylcatechol; photometer