ASTM D3237 Test Method for Lead In Gasoline By Atomic Absorption Spectroscopy
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:
11.1.1 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 the following values only in one case in twenty:
0.005 g/U.S gal (1.3 mg/L)

11.1.2 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:
0.01 g/U.S gal (2.6 mg/L)

11.2 Bias - The bias for this test method was determined by two individual laboratories analyzing standard reference materials.


The values obtained are within the repeatability of the test method and indicate no bias.

12. Keywords
12.1 atomic absorption; gasoline; lead; lead-free