Clean Diesel

Diesel Emissions Quantifier (DEQ)

Use the DEQ

The Diesel Emissions Quantifier (DEQ)

  • Provides an interactive, web-based tool for users with little or no modeling experience.
  • Evaluates clean diesel projects and upgrade options for medium-heavy and heavy-heavy duty diesel engines.
  • Estimates baseline emissions, reduced emissions, cost effectiveness for NOx, PM2.5, HC, CO and CO2, and PM-related health benefits.
  • Cannot provide estimates for Category 3 marine engines.
  • May not be used for State Implementation Plans (SIPs) and Conformity.  Consult your EPA Regional Office or SIP and Conformity guidance documents.

Helpline and Resources

Phone: 877-623-2322                 Email: cleandiesel (

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Use the DEQ