CO₂ Emissions per passenger consider the load factor and are based only on passenger operations (i.e., fuel burn associated with belly freight is not considered). ICEC incorporated complex and regularly updated databases on scheduled flights, passengers/cargo load factors and aircraft fuel burn.

The steps for the estimation of CO₂ emissions per passenger:

STEP 1: Estimation of the aircraft fuel burn

STEP 2: Calculation of the passengers' fuel burn based on a passenger/freight factor which is derived from RTK data

STEP 3: Calculate occupied seats (assumption: all aircraft are entirely configured with economic seats). Seat occupied = Total seats * Load Factor

STEP 4: CO₂ emissions per passenger = (Passengers' fuel burn * 3.16) / Seat occupied

Note: For flights longer than 3000 km, CO₂ emissions per passenger in premium cabin = 2 x CO₂ emissions per passenger in economy