ASTM D5901 test method for freezing point of aviation fuels (optical method)
ASTM D5901 standard test method for freezing point of aviation fuels (automated optical method)
12. Report
12.1 Report the temperature of crystal disappearance recorded in 11.5 to the nearest 0.1°C as the freezing point, Test Method D5901.
13. Precision and Bias
13.1 Precision - The precision of this test method as determined by the statistical examination of the interlaboratory test results is as follows:
13.1.1 Repeatability - The difference between two 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 this test method, exceed 0.46°C only in one case in twenty.
13.1.2 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, in the normal and correct operation of this test method, exceed 1.43°C only in one case in twenty.
13.2 Bias - Because there are no liquid hydrocarbon mixtures of known freezing point, which simulate aviation fuels, bias cannot be established.
13.3 Relative Bias - The current interlaboratory tests indicate that there is no relative bias between this automated test method and Test Method D2386.
13.4 The precision data were developed in a 1994 cooperative test program using 14 samples of fuel. These samples covered the range of aviation turbine fuel products including Jet A, Jet A1, Jet B, JP-4, and JP-5. Some samples were hydrocracked or hydrotreated, or both. Fifteen laboratories participated with the manual Test Method D2386 apparatus and ten laboratories participated with the automated apparatus described in this test method. Information on the type of samples and their average freezing point are in the research report.
14. Keywords
14.1 automated freezing point; aviation gasoline; aviation turbine fuels; freezing point
