1.1 This test method specifies a rapid screening method using flow analysis by Fourier transform infrared (FA-FTIR) spectroscopy with partial least squares (PLS-1) processing for the determination of the fatty acid methyl ester (FAME) content of aviation turbine fuel (AVTUR), in the range of 20 to 150 mg/kg.
???Specifications falling within the scope of this test method are: Specification D1655 and Defence Standard 91-91.
???This test method detects all FAME components, with peak IR absorbance at approximately 1749 cm-1 and C8 to C22 molecules, as specified in standards such as Specification D6751 and EN 14214. The accuracy of the method is based on the molecular weight of C16 to C18 FAME species; the presence of other FAME species with different molecular weights could affect the accuracy.
???Additives such as antistatic agents, antioxidants and corrosion inhibitors are measured with the FAME by the FTIR spectrometer. However the effects of these additives are removed by the flow analysis processing.
???FAME concentrations from 150 mg/kg to 500 mg/kg, and below 20 mg/kg can be measured but the precision could be affected.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.