Division 2.3.2.3 F1
At the request of the manufacturer and with approval of the approval authority, the interpolation line may be extrapolated to a maximum of 3 g/km above the CO2 emission of vehicle H and/or below the CO2 emission of vehicle L. This extension is valid only within the absolute boundaries of the interpolation range specified in paragraph 2.3.2.2.
For the application of a road load matrix family, extrapolation is not permitted.
When two or more interpolation families are identical regarding the requirements of paragraph 5.6. of this Annex, but are distinct because their overall range for CO2 would be higher than the maximum delta specified in paragraph 2.3.2.2., then all individual vehicles of identical specification (e.g. make, model, optional equipment) shall belong to only one of the interpolation families.