An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Verified Technologies for SmartWay and Clean Diesel

Nett Technologies, Inc.—BlueMAX™ 100 Urea-Based Selective Catalytic Reduction (SCR) System

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

On this page:

Technology specifications

Engine Model/Application

Nonroad, 4-cycle, non-EGR diesel engines, originally manufactured model years 1996 - 2008 and, originally certified without a catalyst to EPA Tier 1, 2, or 3 standards

Retrofit Fuel, Max Sulfur 15 parts per million (ppm)
Reduction in particulate matter (PM) 0%
Reduction in nitrogen oxide (NOx) 65%
Reduction in hydrocarbons (HC) 90%
Reduction in carbon monoxide (CO) 85%

Top of Page

Criteria to achieve emission reductions

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

  1. Must be operated on ULSD fuel (15 ppm).
  2. Exhaust temperature data logging will be performed before each installation, and exhaust temperature must be above 250°C for at least 30% of the normal duty cycle. As there may be significant variations from application to application, Nett Technologies will review actual vehicle operating conditions and perform temperature data-logging prior to retrofitting a vehicle with their SCR system to ensure compatibility.
  3. Each installation will be equipped with a monitoring system that displays warning light(s) visible to the operator providing urea tank level and diagnostic information. The monitoring system will also store diagnostic error codes related to urea tank level and system malfunctions.
  4. The vehicle shall not be equipped with a crankcase oil burning system and the engine should be well maintained and not consume lubricating oil at a rate greater than that specified by the engine manufacturer.
  5. The vehicle or equipment is not sold or operated in geographic areas where the urea solution may freeze (-11°C).
  6. To ensure the appropriate urea is purchased and that the engine's urea tank is never empty, the customer is required to maintain urea purchase receipts and refill records and make them available to Nett Technologies upon request. Urea usage log and service log documentation will be collected by Nett Technologies and dealers on a quarterly basis each year.
  7. To ensure that urea is readily available, the system will only be offered to centrally fueled fleets that have or are planning to have urea refilling capability.

Top of Page

Verification Letter from EPA

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.