1. This test method uses a glass hydrometer to cover the laboratory determination of the density, relative density (specific gravity), or API gravity or crude petroleum, petroleum products, or mixtures of petroleum and non-petroleum products normally handled as liquids, and having a Reid vapor pressure of 101.325 kPa (14.696 psi) or less.
  2. Density, relative density (specific gravity), or API gravity is a factor governing the quality of crude petroleum. However, this property of petroleum is an uncertain indication of its quality unless correlated with other properties.