California Air Resources Board

• Updated Emissions Impacts Summary on Ships, Trucking, Locomotive, and Cargo Handling Equipment
• OGV Inventory Documentation: Longer documentation covering CARBs detailed emission inventory for all vessel operation
• EMFAC Inventory Documentation: Longer documentation covering CARBs trucking emission inventory 
• Locomotive Documentation: Longer documentation covering CARBs rail emission inventory
• Cargo Handling Equipment Documentation: Longer documentation covering CARBs emission inventory for cargo handling equipment at ports and railyards.
• Existing Vessel Programs

• Emissions Impacts Summary on Ships, Trucking, Locomotive, and Cargo Handling Equipment

Freight Congestion Impacts from Containerships, Trucks, Locomotives, Cargo Handling Equipment - Posted January 2022

• Emissions Impacts Summary on Ships, Trucking, Locomotive, and Cargo Handling Equipment

Containerships Anchored at San Pedro Bay Ports - Posted November 2021

• Emissions Impacts Summary on Ships

Freight Congestion Impacts from Containerships, Trucks, Locomotives - Posted September 2021

• Emissions Impacts Summary on Ships, Trucking, and Locomotive

Containerships Anchored at San Pedro Bay Ports and Port of Oakland - Posted June 2021

• Emissions Impacts Summary on Ships

Off-Road Diesel Engine Emissions Factors

• Emission Factors 2017 Updates
  • 2017 Off-road Diesel Emission Factors
  • 2017 Off-road Emissions Factor Documentation
• Other References
  • Reference: Previous 1999 Off-road Diesel Emission Factors
  • Off-Road Diesel New Engine Emission Standards
  • Off-Road Diesel HC to Rog/Tog Ratio

Agricultural Equipment

• Equipment Class: Agricultural equipment such as tractors, combines, cotton pickers, and equipment used at agricultural first processors such as forklifts and loaders
• Includes: Self-propelled equipment of all horsepowers and fuels
• Emissions Inventory
  • 2021 Agriculture Emissions Inventory Documentation 
  • Public Webinar Slides: 2021 Agriculture Equipment Emission Inventory - July 15, 2021
• Additional Links
  • San Joaquin Valley Tractor Incentive Program Reports and Details
  • ARB Agricultural Tractor Page

Cargo Handling Equipment (CHE)

• Equipment Class: Equipment used at ports and intermodal rail yards
• Includes: Diesel, propane, gasoline, and electric equipment
• Data Sources: Inventory is based on 2019 reports from Port of Los Angeles, Port of Long Beach, and Port of Oakland, and 2019 data reported to CARB for intermodal railyards and ports not previously listed.
• Emissions Inventory
  • 2022 Documentation
• Additional Links
  • CHE Webpage

Construction, Mining, Industrial and Oil Drilling Equipment over 25hp, Diesel, Subjected to In-Use Regulation

• Equipment Class: Self-propelled equipment used in all off-road applications (except for agriculture), this includes but is not limited to construction, mining, oil drilling and industrial
• Includes: Over 25 horsepower, self-propelled, diesel equipment only
• Emissions Inventory
  • 2022 Inventory Model (Access Database) and Inventory Documentation
• Additional Links
  • 2022 Rulemaking Page
• Data Sources: Inventory based on DOORS reporting data from 2008/2009. Growth is based on construction-starts forecast, updated in 2011

Construction, Mining, Industrial and Oil Drilling Equipment, Diesel and Gasoline of all horsepower, Not Subject to In-Use Regulation

• Equipment Class: Construction and mining and industrial equipment such as small backhoes, mini-excavators or other small equipment, forklifts, etc.
• Includes: Diesel under 25 horsepower, or gasoline of all horsepowers, self-propelled
• Data Sources: Inventory is based on the Off-Road 2007 model

Commercial Harbor Craft (CHC)

• Equipment Class: Harbor craft, barges, commercial fishing, tugboats used at ports
• Includes: Diesel vessels
• Data Sources: 2019 CARB reporting data, Merchant Vessel database from US Coast Guards
• Emissions Inventory:
  • 2021 Inventory Documentation 
  • 2021 Commercial Harbor Craft Model: Baseline 
  • 2021 Commercial Harbor Craft Model: Proposed Rule Scenario 
• Additional Link
  • Rulemaking Page
• Archive
  • 2007 Inventory Documentation
  • 2007 and 2009 Commercial harbor craft inventory models and instructions
    • Harbor Craft
    • Crew and Supply Vessels
    • Barge and Dredge

Forestry Equipment

• Equipment Class: Forestry equipment includes mobile equipment used for on-site logging and mill operations.
• Includes: self-propelled diesel equipment of all horsepowers
• Data Sources: Forestry-specific statewide survey, on-site operations and mill logging activity, timber harvest statistics, and geographical information on logging activities. 
• Emissions Inventory
  • 2021 Forestry Equipment Emissions Inventory Documentation. 

Large Spark-Ignition (Forklift) Equipment 

• Equipment Class: Large Spark-Ignition (LSI) equipment includes forklifts, sweeper/scrubbers, and tow tractors used in industrial operations including but not limited to manufacturing, wholesale, transportation and utilities, and retail.
• Includes: natural gas and gasoline-powered equipment of all horsepowers
• Data Sources: DOORS 2020 LSI Database, DOORS 2020 Fleet Surveys, Fullerton Survey, 2020 ITA California and National Forklift Sales, and Census survey on industrial warehouse space.
• Emissions Inventory:
  • Webcast for CARB Draft 2022 LSI Emissions Inventory Public Workshop - April 26, 2022
  • Second Public Workshop Slides for CARB Draft 2023 LSI Emissions Inventory - January 24, 2023

Locomotives

• Presentation: Draft Updates to the Locomotive Emission Inventories for September 3, 2020 Webinar

• Freight Locomotives: Class I
  • Equipment Class: Locomotive engines used in all freight applications
  • Includes: Diesel locomotives
  • Data Sources: Class I Inventory is based on 2010 ~ 2018 data from Class I Locomotive companies in California.
  • Emissions Inventory
    • 2021 Line Haul / Class I Documentation 
    • 2021 Emission Inventory Aggregated at County/Air Basin/Statewide
  • Additional Links
    • ARB Locomotive and MOU Page
       
• Locomotives - Class I Switchers
  • Equipment Class: Switcher locomotives operating at Class I Rail Yards in California
  • Includes: Diesel locomotives
  • Data Sources: 2017 base year data provided by Class I Locomotive companies in California
  • Emissions Inventory
    • 2022 Class I Switcher Rail Yard Documentation
       
• Locomotives - Freight Short Line / Class III
  • Equipment Class: Local or regional freight applications
  • Includes: Diesel locomotives
  • Data Sources: Data received for 2016 from most Class III rail lines in California
  • Emissions Inventory
    • 2017 Short Line / Class III Documentation
    • 2017 Emissions Inventory Aggregated at County Level: Higher level of detail withheld to protect business confidential information
       
• Locomotives - Passenger
  • Equipment Class: Locomotive engines used in any commuter or passenger application
  • Includes: Diesel or electric locomotives.
    • Data Sources: Data received for 2016 from major passenger rail lines in California
    • Emissions Inventory
      • 2017 Passenger Documentation
      • 2017 Emissions Inventory Aggregated at County Level: Higher level of detail withheld to protect business confidential information
         
• Locomotives – Military and Industrial
  • Equipment Class: Military and Industrial locomotives operating in California
  • Includes: Diesel locomotives
  • Data Sources: Data received for 2020 from M&I locomotive operators in California
  • Emissions Inventory
    • 2022 Military and Industrial Locomotive Inventory Documentation

Ocean Going Vessels

• Equipment Class: Ocean going vessels
• Includes: Diesel main, auxiliary and boiler engines on ocean going vessels greater than 400 feet in length, 10,000 gross tons
• Emissions Inventory
  • 2021 OGV Emissions Inventory Documentation
• Additional Links
  • Port Congestion Impacts on Emissions
  • Rulemaking Page
• Archive
  • ​​​​2019 At Berth Inventory
    • OGV At Berth Model (Access database, October 18, 2019)
    • 2019 At Berth Methodology Documentation

Portable Equipment OVER 50 Hp, Diesel, Subject to Portable ATCM (Updated, October 2017)

• Equipment Class: Portable engines
• Includes: Engines over 50 horsepower, diesel only
• Data Sources: 2016 Portable Engine Registration Program data (PERP)
• Emissions inventory
  • 2017 Inventory Model
  • 2017 Documentation
• Additional Links
  • Rulemaking Page

Portable Equipment UNDER 50 Horsepower, Diesel and Gasoline, Not Subject to Portable ATCM

• Equipment Class: Portable Engines
• Includes: Diesel under 50 horsepower, or gasoline of all horsepowers, portable (not self propelled, not stationary)
• Data Sources: Inventory is based on the OFFROAD2007 model

Transport Refrigeration Units (TRU)

• Equipment Class:Transport Refrigeration Units (TRUs)
• Includes: All Horsepower (all under 50hp), TRUs for trucks, trailers, containers, all fuels (currently only diesel)
• DRAFT 2019 Emission Inventory Methodology: For public comment prior to official release in Summer 2020
• Data Sources: 2011 ARBER TRU Reporting Database
• Emissions Inventory
  • 2021 Emission Inventory Documentation
  • 2021 Emission Inventory Model Programming and Inputs

• Off-Road Gas Equipment

EMFAC2014 (U.S. EPA Approved)

• EMFAC2014 Software Installation Package (v1.0.7)
• EMFAC2014 Update (v1.0.7) Public Release Notice
• EMFAC2014 User's Guide
• EMFAC2014 Technical Documentation, PL Handbook
• Comprehensive Table of EMFAC Topics

EMFAC2014 Updates

Updates From v1.0.1 to v1.0.7 

EMFAC2011

• EMFAC2011 Release Document
• EMFAC2011 User's Guides: LDV, HD, SG, PL
• EMFAC2011 Technical Documentation, PL Handbook
• EMFAC2011 Software Installation Packages: LDV, HD, PL
• EMFAC2011 Idling Emission Rates

EMFAC2007

• Software
• User's Guide
• Technical Memos and Support Documents
  • EMFAC2007 population update
  • Corrections to heavy-duty gas cap benefits
  • Updating vehicle miles traveled and speed distributions in EMFAC2007
    • November 13, 2006
    • September 12, 2006
    • July 20, 2006
  • Redistribution of heavy-heavy duty diesel truck vehicle miles traveled in California
  • Coding modifications to evaporative emissions algorithms
  • Revision of heavy-heavy duty diesel truck emission factors and speed correction factors
    • Original document
    • Amendment
  • Revised planning relative humidity profiles
  • Revised planning temperature profiles
  • Increased evaporative emissions from on-road motor vehicles due to ethanol permeation
    • November 7, 2006
    • November 1, 2005
  • Modifications to the inspection and maintenance programs in the working draft of EMFAC2007
  • On-road emissions inventory fuel correction factors
  • Coding modifications to correct errors in EMFAC2002
  • Revised brake wear PM emission factor
  • Modification of mileage accrual rates
  • Determination of statewide percent of heavy-heavy duty diesel truck (HHDDT) by count

EMFAC2002

• Software
• User's Guide
• Technical Memos and Support Documents
  • Examples (zipped file)
  • Revised Implementation Schedule LEVII
  • Correct Usage Rates for School Buses
  • Correct Monthly Average Gasoline RVP
  • Extended Idle for School Buses
  • Correction to 2007+ HDD PM Emission Rates
  • Extended Idle for Heavy-Duty Trucks
  • Modification of Passenger Car Mileage Accrual Rates
  • Update Speed Distribution
  • Updated Vehicle Miles Traveled
  • Updated Vehicle Miles Traveled (SCAG)
  • Update Population and Registration Distributions
  • Revise Phase 3 Gasoline Fuel Correction Factor Start Date
  • Standards-Ratio Factors for Tire Wear and Brake Wear PM
  • Revising the Cutpoints for the Enhanced Inspection and Maintenance Program
  • Correct Banning from SSAB to SCAQMD
  • Additional Changes to Forecast Estimates of Vehicle Activity from changing Population of Age 45 Vehicles

EMFAC2001

• Software
• User's Guide
• Technical Memos and Support Documents
  • EMFAC2001 Documentation
  • ZEV Amendments
  • Workshop Cover Letter and Itinerary
  • Workshop Presentation

EMFAC2000

• Table of Contents
• Executive Summary
• Model History
• All Support Documents
  • Activity
  • Correction
  • EF
  • Emissions
  • Other
• Appendices

• EMFAC 2007 Population Technical Memo Update
• Corrections to Heavy-Duty Gas Cap Benefits
• Coding Modifications To Evaporative Emissions Algorithms 
• Revised Planning Relative Humidity Profiles 
• Redistribution Of Heavy-Heavy Duty Diesel Truck Vehicle Miles Traveled In California
• Revised Planning Temperature Profiles 
• On-Road Emissions Inventory Fuel Correction Factors
• Modifications To The Inspection And Maintenance Programs In The Working Draft Of EMFAC2007
• Revise Brake Wear PM Emission Factor
• Coding Modifications To Correct Errors In EMFAC2002
• Determination of Statewide Percent of Heavy-Heavy Duty Diesel Truck (HHDDT) by County

• EPA Approval Letter (5/26/23)
• Appendix B:  EMFAC2017 Interim Adjustment Factors (5/26/23)

• EMFAC2017 Software Installation Package (v1.0.3)
• EMFAC2017 Update (v1.0.3) Public Release Notice
• EMFAC2017 Software Installation Package (v1.0.2)
• EMFAC2017 Update (v1.0.2) Public Release Notice
• EMFAC2017 User's Guide
• EMFAC2017 PL Handbook
• EMFAC2017 Technical Documentation

Updates from v1.0.2 to v1.0.3

• Fixed a bug in custom activity (SG) mode related to multi-year speed profiles entries
• Fixed a bug related to methane (CH4) speciation for gasoline vehicles

Updates from v1.0.1 to v1.0.2

• Off-Model Adjustment Factors for Recently-Adopted Regulations
• Off-Model Adjustment Factors for Recently-Adopted Regulations (Appendix)

• EPA Approval Letter - 5/6/2026
• Attachment B – Guidance for CTC In-State EMFAC Off-Model Adjustments
• Appendix B – CTC In-State Factors

• Guidance For Applying EMFAC2021 Off-Model Adjustment Factors for PL Assessment
• EMFAC2021 Factors for PL Guidance

EMFAC2021 Off-Model Adjustment Factors to Remove the Impact of Advanced Clean Trucks, Zero-Emission Airport Shuttle, Heavy-Duty Omnibus and Warranty Phase I Regulations

• EPA Off-Model Adjustment Factors Approval Letter - 11/21/2025
• Attachment A – Description of EMFAC2021 Adjustment Factors
• Appendix A – EMFAC2021 Adjustment Factors

EMFAC2021 Off-Model Greenhouse Gas Adjustment Factors to Remove the Impact of Advanced Clean Trucks, Zero-Emission Airport Shuttle, Heavy-Duty Omnibus and Warranty Phase I Regulations

• EMFAC2021 GHG Adjustment Factors

• EMFAC2021 approval notice in the Federal Register - 11/15/2022
• EMFAC2021 (v1.0.2) Public Release Notice - 5/2/22
• EMFAC2021 (v1.0.1) to (v1.0.2) Updates - 5/2/22
• EMFAC2021 Software Installation Package (v1.0.2) - 5/2/22
• EMFAC2021 (v1.0.1) Public Release Notice - 4/30/21
• EMFAC2021 Software Installation Package (v1.0.1) - 4/28/21
• EMFAC2021 (v1.0.0) to (v1.0.1) Updates - 4/28/21
• EMFAC2021 PL Handbook - 3/26/21
• EMFAC2021 Technical Document - 4/28/21
• PHEV Start Analysis Draft Memo - 3/26/21
• EMFAC2021 (v1.0.0) Public Release Notice - 1/15/21
• EMFAC2021 User’s Guide