This specification covers seven grades of diesel fuel oils suitable for various types of diesel engines. These grades are: Grade No. 1-D S15; Grade No. 1-D S500; Grade No. 1-D S5000; Grade No. 2-D S15; Grade No. 2-D S500; Grade No. 2-D S5000; and Grade No. 4-D. The requirements specified for diesel fuel oils shall be determined in accordance with the following test methods: flash point; cloud point; water and sediment; carbon residue; ash; distillation; viscosity; sulfur; copper corrosion; cetane number; cetane index; aromaticity; lubricity; and conductivity.

1.1 This specification covers seven grades of diesel fuel oils suitable for various types of diesel engines. These grades are described as follows:

1.1.1 Grade No. 1-D S15—A special-purpose, light middle distillate fuel for use in diesel engine applications requiring a fuel with 15 ppm sulfur (maximum) and higher volatility than that provided by Grade No. 2-D S15 fuel.

1.1.2 Grade No. 1-D S500—A special-purpose, light middle distillate fuel for use in diesel engine applications requiring a fuel with 500 ppm sulfur (maximum) and higher volatility than that provided by Grade No. 2-D S500 fuel.

1.1.3 Grade No. 1-D S5000—A special-purpose, light middle distillate fuel for use in diesel engine applications requiring a fuel with 5000 ppm sulfur (maximum) and higher volatility than that provided by Grade No. 2-D S5000 fuels.

1.1.4 Grade No. 2-D S15—A general purpose, middle distillate fuel for use in diesel engine applications requiring a fuel with 15 ppm sulfur (maximum). It is especially suitable for use in applications with conditions of varying speed and load.