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Verified Technologies for SmartWay and Clean Diesel

Clean Diesel Technologies, Inc. – Purifilter OR Diesel Particulate Filter (DPF) for Non-Road Applications System

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

On this page:

Technology specifications

Engine Model/Application

Nonroad, Tier 1 or Tier 2 or Tier 3 diesel engines, certified with a maximum PM level of 0.20 g/bhp-hr with power ratings 100 ≤ Horsepower ≤ 603hp

Retrofit Fuel, Max Sulfur 15 parts per million (ppm)
Reduction in particulate matter (PM) 90%
Reduction in nitrogen oxide (NOx) n/a
Reduction in hydrocarbons (HC) 90%
Reduction in carbon monoxide (CO) 85%

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Criteria to achieve emission reductions

The following operating criteria must be met in order for appropriately retrofitted engines to achieve the above emissions reductions:

  1. The engine must be operated on ultra-low sulfur diesel fuel (ULSD) of 15 ppm or less.
  2. Nonroad engines must have EPA particulate matter (PM) certification levels less than or equal to 0.20 g/bhp-hr (0.27g/kW-hr) and greater than 0.015 g/bhp-hr (0.02g/kW-hr).
  3. The engine’s exhaust must produce a NOx/PM ratio of at least 18 or more. CDTi will make an assessment of the suitability of candidate engines, based upon certification emission levels or emission test data.
  4. CDTi approved dealer shall perform an engine pre-assessment that assures the engine is at a minimum operating condition to prevent excess soot build up. The dealer will provide the owner with a copy of the pre-assessment.
  5. CDTi will install the Emissions Device Monitor with the Purifilter OR System to constantly monitor backpressure and temperature on all vehicles equipped with this DPF that notifies the operator when the backpressure limit is reached.
  6. The engine must be well maintained and not consume lubricating oil at a rate greater than that specified by the engine manufacturer.
  7. The engine must not have been originally certified or equipped an original equipment DPF, DOC, or SCR system.
  8. The engine must be in proper operating condition, well maintained, and not consume lubricating oil at a rate greater than that specified by the engine manufacturer. 
  9. All engines with power ratings below 100 hp or above 603 hp or 19L engine displacement are excluded.
  10. To ensure engine out opacity levels are comparable to those reported by the original engine manufacturer, written approval must be given to the installer/distributor prior to retrofit for engines with OE reported peak opacity values above 30%.
  11. Minimum duty cycle requirements of 10% above 300 C must be met.

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Verification Letter from EPA

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