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Verified Technologies for SmartWay and Clean Diesel

Clean Diesel Group LNF System

Verified Technologies for SmartWay and Clean Diesel

This retrofit technology is included on EPA's Verified Technologies List for Clean Diesel.

On this page:

Technology specifications

Engine Model/Application

Highway model year 1993 through 2006 and have an engine family name listed in the Attachment A

Retrofit Fuel, Max Sulfur 15 parts per million (ppm)
Reduction in particulate matter (PM) 90%
Reduction in nitrogen oxide (NOx) 0%
Reduction in hydrocarbons (HC) 90%
Reduction in carbon monoxide (CO) 80%

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Criteria to achieve emission reductions

The following criteria must be met in order for appropriately retrofitted engines to achieve the aforementioned emission reductions:

  1. The engine must be certified to a PM emission level of at most 0.1 grams per brake horsepower-hour (g/bhp-hr), and greater than 0.01 g/bhp-hr.
  2. The engine must be used by an on-road motor vehicle with a manufacturer's Gross Vehicle Weight Rating of over 14,000 pounds.
  3. The application must have a duty cycle with an exhaust temperature profile that: Results in a Weighted Average Temperature (WAT) that is at least 237 degrees Celsius; or Is either greater than 235 degrees Celsius for at least 40 percent of the time or greater than 300 degrees Celsius for at least 10 percent of the time.
  4. The engine must be rated to at least 100 horsepower (hp) and no more than 600 hp.
  5. The engine may or may not be certified as having exhaust gas recirculation.
  6. The engine must not have a pre-existing original equipment manufacturer (OEM) diesel particulate filter.
  7. The engine may or may not have a pre-existing OEM oxidation catalyst.
  8. The engine must have a four-stroke combustion cycle.
  9. The engine must be turbocharged.
  10. The engine may be mechanically or electronically controlled.
  11. The engine must be well maintained and must not consume lubricating oil at a rate greater than that specified by the engine manufacturer.
  12. Lube oil or other oil must not be mixed with the fuel.
  13. Each vehicle that is a candidate for installation of the LNF system based on the WAT criterion must first have its exhaust temperature measured and recorded for an appropriate period of time during typical operation. CDG or its authorized representative must maintain these data for each LNF-equipped vehicle and make them available to EPA upon request.

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Verification Letters from EPA

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