Emission factor specification
Retrieved 2026-08-25
U.S. Environmental Protection Agency
Source: CO2, CH4, and N2O emissions data for highway vehicles are from Table 2-13 of the EPA (April 2023) Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2021 data. Vehicle-miles data for on-road vehicles are from Tables A-73 - A-75 of the EPA (April 2023) Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2021 data, Annexes. Passenger-miles data for buses are from Table VM-1 of the Federal Highway Administration Highway Statistics (January 2024): 2021 data. Fuel consumption data and passenger-miles data for rail are from Tables A.14 - A.16, 10-10, and 7.3 - 7.4 of the Transportation Energy Data Book: Edition 40 (June 2022): 2019 data. Fuel consumption was converted to emissions by using fuel and electricity emission factors presented in the tables above. Intercity Rail factors from communication with Amtrak, March 2020. These are based on 2019 values. Air Travel factors from 2022 Guidelines to Defra / DECC's GHG Conversion Factors for Company Reporting. Version 2.0 June 2022. Defra air travel emission factors held constant from 2022 release (2018 activity data) to more accurately reflect the current state of business travel as the 2023 Defra release reflects significantly reduced load factors during COVID-19. " "Notes: A Passenger cars are automobiles used primarily to transport 12 people or less for personal travel, and are less than 8,500 lbs in gross vehicle weight. B Light-duty trucks are vehicles that primarily transport passengers such as sport utility vehicles (SUVs) and minivans. This category also includes vehicles used for transporting light-weight cargo which are equipped with special features such as four-wheel drive for off-road operation. The gross vehicle weight normally ranges around 8,500 pounds or less. C Intercity rail: Amtrak long-distance rail between major cities. Northeast Corridor extends from Boston to Washington D.C. Other Routes are all routes outside the Northeast Corridor. D Commuter rail: rail service between a central city and adjacent suburbs (also called regional rail or suburban rail). E Transit rail: rail typically within an urban center, such as subways, elevated railways, metropolitan railways (metro), streetcars, trolley cars, and tramways.
Values are per kgCO₂e/passenger-mile
54.5% of 61 · larger than the median
Compared against 61 factors in the same unit (passenger-mile). Product families may be mixed, so treat it as indicative only. Measuring concrete and steel sheet with the same ruler says little.
4 items provided by the source
0 under the same product · 6 with a similar value
| Product · manufacturer | Relation | Edition | Factor (kgCO₂e/passenger-mile) | vs this factor |
|---|---|---|---|---|
| Air Travel · U.S. Environmental Protection Agency | Similar value | — | 0.134267 | ▼ 0.0% |
| Air Travel · U.S. Environmental Protection Agency | Similar value | — | 0.132267 | ▼ 1.5% |
| Air Travel · U.S. Environmental Protection Agency | Similar value | — | 0.137296 | ▲ 2.2% |
| Air Travel · U.S. Environmental Protection Agency | Similar value | — | 0.130365 | ▼ 2.9% |
| Air Travel · U.S. Environmental Protection Agency | Similar value | — | 0.130237 | ▼ 3.0% |
| Air Travel · U.S. Environmental Protection Agency | Similar value | — | 0.130237 | ▼ 3.0% |