This standard details the general bomb test method for determination of the amount of sulfur in lubricating oils with additives, additive concentrates, lubricating greases, and other petroleum products with low volatilities. This test method entails oxidizing samples by combustion in a bomb containing oxygen under pressure. The amount of sulfur is determined by gravimetry. Materials needed for the test include a combustion bomb, sample cup, firing wire, ignition circuit, and a cotton wicking or nylon sewing thread. All reagents, samples, and other chemicals used for the test should conform to the required concentration and purity.

1.1 This test method covers the determination of sulfur in petroleum products, including lubricating oils containing additives, additive concentrates, and lubricating greases that cannot be burned completely in a wick lamp. The test method is applicable to any petroleum product sufficiently low in volatility that it can be weighed accurately in an open sample boat and containing at least 0.1 % sulfur.

Note 1—This test method is not applicable to samples containing elements that give residues, other than barium sulfate, which are insoluble in dilute hydrochloric acid and would interfere in the precipitation step. These interfering elements include iron, aluminum, calcium, silicon, and lead which are sometimes present in greases, lube oil additives, or additive oils. Other acid insoluble materials that interfere are silica, molybdenum disulfide, asbestos, mica, and so forth. The test method is not applicable to used oils containing wear metals, and lead or silicates from contamination. Samples that are excluded can be analyzed by Test Method D 1552.

1.2This 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. See 3.2 for specific precautionary directions incorporated in the test method.