This specification covers the selection of fuels for gas turbines, excepting gas turbines used in aircraft, for the guidance of interested parties such as turbine manufacturers and the suppliers and purchasers of fuel oils. The specification sets forth the properties of fuels at the time and place of custody transfer to the user. The fuels shall be homogeneous mixtures of hydrocarbon oils free of inorganic acid, and free of excessive amounts of solid or fibrous foreign matter likely to make frequent cleaning of suitable strainers necessary. All grades containing residual components shall remain homogeneous in normal storage and not separated by gravity into light and heavy oil components outside the viscosity limits for the grade. The following test methods shall be performed to determine certain properties: flash point test, pour point test, water and sediment test, carbon residue test, ash test, distillation test, viscosity test, density test, and sulfur test.