EPA Tier Emissions Compliance
Starting in 2006, the EPA began to apply air pollution regulations for Stationary Compression Ignition Internal Combustion Engines (CI ICE). The EPA air pollution restrictions are very extensive, and include requirements for engine generator exhaust emissions. From 2006 through 2015, the goal of this program was a gradual reduction of allowed emissions of four pollutant groups (nitrogen oxides, particulate matter, carbon monoxide, and non-methane hyrdocarbons).
Engine manufacturers and end users are responsible for working together to achieve operational compliance. This has included manufacturers building increasingly clean burning engines, and end users purchasing the correct EPA Tier certified engine and the appropriate engine exhaust after treatment. Because there is no single solution to effectively treat all four pollutant groups, the only way EPA Tier compliance can be verified is by field testing the generator and it's after treatment system.
In addition to cleaner burning engines and exhaust after treatments, achieving EPA compliance has also required that the sulfer content of diesel fuel be lowered, all of these aspects working together combine to make up the EPA's multi-pronged approach to achieving clean air.
Because the EPA Tier Compliance regulations vary for emergency vs. non-emergency generator sets, and required Tier level compliance also varies by the size and year of the generator set, it's a good idea to check your local state government website for the latest information.
Details about EPA Tier Compliance regulations as they apply to diesel generators can also be found on these websites:
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