1.1 This test method covers the determination of the amount of carbon residue (Note 1) left after evaporation and pyrolysis of an oil, and it is intended to provide some indication of relative coke-forming propensity. This test method is generally applicable to relatively nonvolatile petroleum products which partially decompose on distillation at atmospheric pressure. This test method also covers the determination of carbon residue on 10 % (V/V) distillation residues (see Section 10). Petroleum products containing ash-forming constituents as determined by Test Method D482, will have an erroneously high carbon residue, depending upon the amount of ash formed (Notes 2 and 3). Note 1: The term carbon residue is used throughout this test method to designate the carbonaceous residue formed during evaporation and pyrolysis of a petroleum product. The residue is not composed entirely of carbon, but is a coke which can be further changed by pyrolysis. The term carbon residue is continued in this test method only in deference to its wide common usage. Note 2: Values obtained by this test method are not numerically the same as those obtained by Test Method D189, or Test