Division 2.4.2.2

For engines fuelled with CNG, the manufacturer may test the engine on the reference fuels G_R and G₂₃, or on the reference fuels G₂₅ and G₂₃, or on the equivalent fuels created using admixtures of pipeline gas with other gases as specified in Appendix 1 of Annex IX, in which case the EU type-approval is only valid for the H-range or the L-range of gases respectively.