Automotive and locomotive diesel fuels, in general, are derived from petroleum refinery products which are commonly referred to as middle distillates. Middle distillates represent products which have a higher boiling range than gasoline and are obtained from fractional distillation of the crude oil or from streams from other refining processes. Finished diesel fuels represent blends of middle distillates and may contain other blending components of substantially non-petroleum origin, such as biodiesel fuel blend stock, and/or middle distillates from non-traditional refining processes, such as gas-to-liquid processes.
The properties of commercial distillate diesel fuels depend on the refinery practices employed and the nature of the crude oils from which they are derived. Thus, they may differ both with and within the region in which they are manufactured. Such fuels generally boil, at atmospheric pressure, over a range between 130 °C and 400 °C (approximately 270 °F to 750 °F). Their makeup can represent various combinations of volatility, ignition quality, viscosity, sulfur level, density, and other characteristics. Additives may be used to impart specific properties to the finished diesel fuel.
Diesel fuel accounts for approximately 20% of all crude oil consumed in the U.S. The oil, automobile, and fuel additive industries have worked together for many decades to determine the composition and properties of diesel fuels required to provide satisfactory vehicle operation. This work is ongoing. Since the late 1960s, environmental concerns have led to federal and state regulations to reduce emissions from vehicles and from petroleum storage and transportation facilities.
This SAE Surface Vehicle Standard discusses the characteristics of diesel fuels, common Standard Test Methods, specifications developed by ASTM International and others, government regulations, and the effects of diesel fuel composition and properties on vehicle performance, fuel economy, emissions, and durability. This historical document provides useful information for the proper and safe use of diesel fuel and is not intended to be a product specification.