This test method provides a means for the comparison of waterborne oil samples with potential sources. The waterborne samples may be emulsified in water or obtained from beaches, boats, oil-soaked debris, and so forth.

The unknown oil is identified by the similarity of its infrared spectrum with that of a potential source oil obtained from a known source, selected because of its possible relationship to the unknown oil.

The analysis is capable of comparing most oils. Difficulties may be encountered if a spill occurs in an already polluted area, that is, the spilled-oil mixes with another oil.

In certain cases, there may be interfering substances which require modification of the infrared test method or the use of other test methods (see Practice D 3326, Method D.)

It is desirable, whenever possible, to apply other independent analytical test methods to reinforce the findings of the infrared test method (see Practice D 3415).

1.1 This test method provides a means for the identification of waterborne oil samples by the comparison of their infrared spectra with those of potential source oils.

1.2 This test method is applicable to weathered or unweathered samples, as well as to samples subjected to simulated weathering.

1.3 This test method is written primarily for petroleum oils.

1.4 This test method is written for linear transmission, but could be readily adapted for linear absorbance outputs.

1.5 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. Specific precautionary statements are given in Section 8.