ASTM D3606 Standard Test Method for Determination of Benzene and Toluene in Finished Motor and Aviation Gasoline by Gas Chromatography
14. Report
14.1 Report the benzene and toluene contents in liquid volume percent to the nearest 0.1 %.
15. Precision and Bias
15.1 The following criteria should be used for judging the acceptability of results (95 % confidence). The user should choose the precision statement that reflects the concentration range of each component under study.
15.1.1 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 values in Table 2 only in 1 case in 20:
15.1.2 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 the test method, exceed the values in Table 3 only 1 case in 20:
NOTE 15 - In order to reflect changes in gasoline composition, the precision for this test method was determined in 1994 using both conventional gasolines as well as gasolines containing oxygenates (ethers such as methyl tert-butyl ether, ethyl tert-butylether and tert-amylmethylether). The precision statement does not reflect results for gasolines that can contain alcohols. This precision should be used when the concentration of benzene (0.1 to 1.5 volume %) and toluene (1.7 to 9 volume %) fall within the specified range. The sample composition and results of the cooperative study are filed at ASTM headquarters as RR:D02-1042.
NOTE 16 - The precision was determined using conventional motor gasolines purchased on the open market. This precision should be used when the concentration of benzene exceeds 1.5 volume % and toluene 9 volume %. The sample compositions and results of the cooperative study are filed at ASTM Headquarters as RR:D-02-1042.
15.2 Bias - Since there is no accepted reference method suitable for measuring bias for this method, no statement of bias can be made.
16. Keywords
16.1 aviation gasoline; benzene; gas chromatography; gasoline; toluene