1.1 This test method covers the procedure for determining the concentration of dye Solvent Red 164 in commercially available diesel and burner fuels using visible spectroscopy.

Note 1-This test method is suitable for all No.1 and No.2 grades in Specifications D396 and D975 and for grades DMA and DMB in Specification D2069.

1.2 The concentration ranges specified for the calibration standards are established in response to the Internal Revenue Service dyeing requirements which state that tax-exempt diesel fuel satisfies the dyeing requirement only if it contains the dye Solvent Red 164 (and no other dye) at a concentration spectrally equivalent to 3.9 lb of the solid dye standard Solvent Red 26 per thousand bbl (11.1 mg/L) of diesel fuel.

1.3 The values stated in SI units are to be regarded as the standard.

1.4 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.