The Environmental Protection Agency (EPA) recently tested a clean diesel fuel developed by Dion & Sons for use in stationary sources. This fuel is known as Amber 363 in Southern California and its technology is licensed outside of the Southern California area to Shell Oil Products Company for use as a stationary source fuel. The fuel, hereafter referred to as “Shell LOW NOX Fuel,” was tested in a 1990 model year heavy heavy-duty diesel engine using both the transient Federal Test Procedure (FTP) for on-highway heavy-duty engines, the steady-state FTP for nonroad heavy-duty engines, and the steady-state generator set test cycle. For each test, EPA measured hydrocarbon (HC), carbon monoxide (CO), nitrogen oxides (NOx) and particulate matter (PM) emissions.Transient testing showed that the Shell LOW NOX Fuel lowers NOx, HC and PM emissions with no statistically significant change in CO emissions for both cold-starts and hot-starts when compared to diesel certification test fuel. Steady-state testing using the nonroad test cycle showed that the Shell LOW NOX Fuel decreases PM and HC emissions with no statistically significant in CO and NOx emissions when compared to the base fuel. Steady-state testing using the generator set test cycle showed that the Shell LOW NOX Fuel increases HC and CO emissions with no statistically signifcant changes in NOx and PM emissions when compared to baseline certification diesel test fuel.