There are several areas that have changed drastically during the last few years with diesel engines and will greatly affect the near future of diesel engine technologies. The highway trucking industry was the first to require these changes to meet federal EPA emissions guidelines for diesel engines back in the late 1980s. In the mid1990s these same guidelines were required of the offhighway heavy equipment industry. Now even areas not affected in the past such as the marine, petroleum, and agricultural industries have come under these new requirements. They will change these indus tries in the same way they have previously changed the trucking and heavy equipment industries. During the last 20 years only certain engine horsepower sizes or industries have come under these federal guidelines. However, the 2007, 2010, and 2012 emis sions guidelines will cover and affect all horsepower sizes and industries. Additionally, in most areas the current technologies to meet the 2007 guidelines will not completely meet the 2010 and 2012 requirements without additional technological changes or improvements.