An emission factor is the coefficient that converts an activity datum (such as fuel consumption, electricity use or distance travelled) into a quantity of greenhouse gas emissions. The emission is obtained by multiplying the activity data by the emission factor.
Factors are taken from national and international sources. As critical as which source is used is documenting the choice: the source name, version, year of publication and the item to which it is applied must be recorded.
One of the most frequently asked questions in the verification process is the rationale for the choice of factor. When a factor changes between years, how comparability is preserved must also be explained.
Related terms: Greenhouse Gas Inventory · Scope 1 and Scope 2 Emissions · Base Year
Related training: Corporate Carbon Footprint — ISO 14064-1