1. Scope
1.1 This test method covers the visual determination of the color of a wide variety of petroleum products, such as lubricating oils, heating oils, diesel fuel oils, and petroleum waxes.
NOTE 1 - Test Method D156 is applicable to refined products that have an ASTM color lighter than 0.5. IP Method 17 includes a procedure for measuring the color of undyed, refined products such as gasoline, white spirit, and kerosine by comparison with a series of IP Standard glasses. It also includes a procedure by which petroleum products, except black oils and bitumens, may be measured for tint and depth of color in terms of Lovibond units by a series of red, yellow, and blue glasses.
1.2 This test method reports results specific to the test method and recorded as "ASTM Color."
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.
2. Referenced Documents
2.1 ASTM Standards:
D156 Test Method for Saybolt Color of Petroleum Products(Saybolt Chromometer Method)
D938 Test Method for Congealing Point of Petroleum Waxes, Including Petrolatum
D2500 Test Method for Cloud Point of Petroleum Products
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
2.2 Energy Institute Standard:
IP17 Color by the Lovibond Tintometer
3. Summary of Test Method
3.1 Using a standard light source, a liquid sample is placed in the test container and compared with colored glass disks ranging in value from 0.5 to 8.0. When an exact match is not found and the sample color falls between two standard colors, the higher of the two colors is reported.
4. Significance and Use
4.1 Determination of the color of petroleum products is used mainly for manufacturing control purposes and is an important quality characteristic, since color is readily observed by the user of the product. In some cases, the color may serve as an indication of the degree of refinement of the material. When the color range of a particular product is known, a variation outside the established range may indicate possible contamination with another product. However, color is not always a reliable guide to product quality and should not be used indiscriminately in product specifications.
