This proposal amends UN Regulation No. 115 to list conditions, especially with regard to retrofit systems, to be met by indirect and direct injection vehicles to be considered as belonging to the same vehicle family. Gasoline direct injection vehicles which operate in indirect gas injection mode should be listed in the same family as indirect gasoline injection vehicles, as the applied gas injection technology is the same and provided that at least one such vehicle is tested as parent vehicle according to the requirements of this Regulation.