ASTM D5307 Determination of Boiling Range Distribution of Crude Petroleum by Gas Chromatography
13. Report
13.1 Report the following information:
13.1.1 The temperature to the nearest 0.5°C (1°F) at the IBP and at 1 % intervals, and
13.1.2 The total residue above 538°C to the nearest 0.1 %.
14. Precision and Bias
14.1 The precision of this test method as determined by statistical examination of interlaboratory results is as follows:
14.1.1 Repeatability - The difference between two 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, and in the normal and correct operation of the test method, exceed the values shown in Table 3 only in 1 case in 20.
14.1.2 Reproducibility - The difference between two single independent results obtained by different operators working in different laboratories on identical test material would, in the long run, and in the normal and correct operation of the test method, exceed the values shown in Table 3 only 1 case in 20.
NOTE 3 - Samples included in the study had residues ranging from about 3 to 30 %. Samples with residues outside this range may have different precision.
14.2 Bias - The procedure in this test method for determining the boiling range distribution of crude petroleum by gas chromatography has no bias because the boiling range distribution can only be defined in terms of a test method.
14.2.1 A rigorous, theoretical definition of the boiling range distribution of crude petroleum is not possible due to the complexity of the mixture as well as the unquantifiable interactions among the components (for example, azeotropic behavior). Any other means used to define the distribution would require the use of a physical process such as a conventional distillation or gas chromatographic characterization. This would therefore result in a method-dependent definition and would not constitute a true value from which bias can be calculated.
15. Keywords
15.1 crude oil; gas chromatography; petroleum; simulated distillation
