La directive 97/68/CE prévoit un mécanisme de flexibilité permettant aux fabricants d’équipements d’acheter, au cours de la période séparant deux phases d’émissions, un nombre limité de moteurs non conformes aux limites d’émission du moment, mais qui répondent aux exigences de la phase précédant immédiatement la phase applicable.
Directive 97/68/EC provides for a flexibility scheme to allow equipment manufacturers to purchase, in the period between two emission stages, a limited number of engines that do not comply with the emission limits applicable during that period, but which are approved in accordance with the requirements of the stage immediately preceding the applicable one.