Welcome to OFFROADWeb

This website provides California's emissions inventories of off-road mobile sources in California.

Updates

  • February 2025: Updates (v1.1.3) to reflect the latest emission inventory for Transport Refrigeration Units (TRU2025), and regional codes for In-Use Diesel equipment (construction, mining, oil drilling, and ground support).
  • July 24, 2025: Updates (v1.1.2) to reflect the 2025 off-road emissions factors.
  • July 2025: Updates (v1.1.1) to reflect the baseline emissions without the In-Use Locomotive Regulation for all locomotive categories, and without the Zero-Emission Forklift regulation for LSI Forklifts. Includes inventory updates to Ocean-Going Vessels (OGV2025).
  • February 2025: Updates (v1.1.0) to include minor adjustments to web tool functionality.
  • January 2025: Updates (v1.0.9) to include new categories from the 2024 Aviation equipment inventory and minor updates to Pleasure Craft and Recreational Vehicles inventories.
  • December 2024: Updates (v1.0.8) to to reflect the adopted 2021 SORE Regulation and the 2024 Zero-Emission Forklift Regulation for LSI Forklifts.
  • June 2024: Minor update (v1.0.7) to regional codes for passenger and short line locomotive engines, consistent with the April 2023 In-Use Locomotive Regulation.
  • May 2024: Locomotive Inventory updated (v1.0.6) to include new category of industrial/military locomotive engines. Updates also reflect the April 2023 In-Use Locomotive Regulation for switchers, line haul, passenger, short line, and industrial locomotive engines.
  • September 2023: Launch of new website for off-road emission inventories, separate from EMFAC web platform for on-road emission inventories
  • June 2023: Inventories updated (v1.0.5) include In-Use Diesel (INUSE2022) and Commercial Harbor Craft to reflect adopted regulation
  • May 2023: Start of the Development of a new website for off-road emission inventories
  • February 2023: Minor update (v1.0.4) to all diesel inventories, where CO2 emissions are calculated based on fuel consumption
  • July 2022: Minor update (v1.0.3) to regional codes for all gasoline inventories including Lawn and Garden, Pleasure Craft, Recreational Vehicles, Small Off-Road Equipment, Gas Cans, and Outboard Marine Tanks
  • April 2022: Inventories updated (v1.0.2) include Cargo Handling Equipment (CHE2022), Forestry (2021), and Ocean-Going Vessels (OGV2021)
  • October 2021: Off-road emission inventories now available within EMFAC web platform. Inventories updated (v1.0.1) include Agriculture (AG2021), Commercial Harbor Craft (CHC2021), Transport Refrigeration Unit (TRU2021), Locomotive (LOCO2021), and Small Off-Road Equipment (SORE2020)

Related Resources

Contact Us

This website is operated by the Mobile Source Analysis Branch in the Air Quality Planning and Science Division at the California Air Resources Board. Please contact msei@arb.ca.gov with any questions or comments.