ASTM D1740 Test Method for Luminometer Numbers of Aviation Turbine Fuels
11. Precision and Bias
11.1 The precision of this test method as determined by the statistical examination of interlaboratory test results is as follows.
11.1.1 Repeatability - The difference between successive results obtained by the same operator with the same apparatus under constant operating conditions 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.
Repeatability = 6.1 luminometer numbers
11.1.2 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, exceed the following value only in one case in twenty.
Reproducibility = 8.8 luminometer numbers
NOTE 12 - The preceding precision was obtained in a program using the Luminometer made by ERDCO Engineering Corporation. Equipment not equivalent to this apparatus can give results of different precision.
11.2 The precision of test method is not known to have been obtained in accordance with currently accepted guidelines (for example, in Committee D-2 Research Report RR:D02-1007, "Manual of Determining Precision Data for ASTM Methods and Petroleum Products and Lubricants".
NOTE 13 - Seven laboratories tested nine fuels varying in volatility and luminometer rating. Seven were aviation fuels including fuels meeting Specification D1655, and two were gas turbine fuels (No. 1 and No. 2) as designated in Specification D2880, for Gas Turbine Fuel Oils. One laboratory was excluded from analysis for failure to complete testing. There was no significant variation in precision with luminometer rating level.
11.3 Bias - The procedure in Test Method D1740 has no bias because the value of luminometer numbers can only be determined in terms of the test method.
12. Keywords
12.1 aviation fuel; flame radiation; gas turbine distillate fuels; luminometer number
