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Diesel Emissions Quantifier (DEQ)

Logging in to the DEQ allows you to save and retrieve information for review and/or revision.

Information about Projects Saved Prior to Version 9.0
Updates to the emission factors used in the DEQ may result in different results than calculated previously.
  1. If you saved Tier 4 nonroad engines or replacements prior to version 9.0, you should be aware of the following:
    • The DEQ now asks for additional information about your Tier 4 engine's after-treatment configuration.
    • Editing your project to provide this information will allow the DEQ to more accurately reflect your emissions profile.
  2. For both onroad vehicles and projects involving Tier 4 non-road engines,
    • The baseline emissions for your project may be different than what was calculated using the previous factors.
    • For engine or vehicle replacements, the percent reductions saved with your project were calculated based on the previous factors.
    • Editing your replacement upgrade (by either adding the additional Tier 4 information or altering the new engine model year selection) will update the reduction calculations to reflect the new emissions factors.

Use the DEQ without logging in