ULSD Explained: What Diesel Users in the U.S. and Canada Must Know
Diesel fuel standards have changed significantly over the past two decades, and one term now dominates the conversation: Ultra-Low Sulfur Diesel (ULSD) . If you operate diesel generators , heavy equipment, or commercial engines in the United States or Canada, understanding ULSD isn’t optional—it’s essential. This article explains why ULSD exists, where it’s required, and how it affects diesel-powered equipment across North America. What Makes ULSD Different from Traditional Diesel? ULSD is diesel fuel refined to contain 15 parts per million (ppm) or less sulfur . Older diesel fuels contained far higher sulfur levels, which increased emissions and limited engine technology. Reducing sulfur content made it possible to introduce cleaner, more efficient diesel engines equipped with advanced emissions control systems. The Role of ULSD in Modern Diesel Engines Today’s diesel engines are engineered around low-sulfur fuel. ULSD enables the proper operation of critical components such a...