US EPA Supply Chain Emissions
The EPA's US Environmentally Extended Input-Output dataset provides GHG emission factors for 1,016 U.S. commodities based on the 2017 version of the North American Industry Classification System (NAICS). Developed with GHG emission data from 2021, the factors encompass three types:
- Supply Chain Emissions without Margins (SEF)
- Margins of Supply Chain Emissions (MEF)
- Supply Chain Emissions with Margins (SEF+MEF).
Each record in the dataset provides the amount of each unique GHG emitted per dollar per commodity without the CO2e calculation. The dollar in the denominator of all factors uses purchaser prices in 2021 USD. The supply chain emission factors cover the initial life cycle phases of a product, from material acquisition through manufacture or provision of the good or service.
The factors result from combining two models: the National Greenhouse Gas Industry Attribution Model (NGIAM) and the U.S. Environmentally Extended Input-Output (USEEIO) model. The NGIAM produces totals of the direct emissions by detailed industries, which are then used as input into a selected USEEIO model. From there, direct and indirect emission intensities are derived following data year adjustments and calculations. The final factors adjust to reflect purchaser prices, which are useful with expenditure data.
For more information on the methodology and to access the dataset directly, please visit the website.