DIESEL EXHAUST FLUID

The Definitive Guide to DEF Ever since the Clean Air Act went into effect in 1970, the United States Environmental Protection Agency (EPA) has taken the necessary steps to regulate exhaust emissions from various types of vehicles to reduce harmful air pollution. Diesel engines were not always regulated, even though they used to be a big source of hazardous air pollution. But in 1990, the EPA started the National Clean Diesel Program , which set lower emission standards for diesel engines to continue helping reduce harmful pollutants getting into our air to better protect human health. In response to these new standards, engineers took it upon themselves to come up with a technology to make safer, more efficient exhaust treatment system for diesel engines. That technology is Selective Catalytic Reduction (SCR) that uses diesel exhaust fluid (DEF). What is DEF? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 2 Why SCR? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 3 Handling DEF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 5 Challenges with DEF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 9 The Definitive Guide to DEF Table of Contents