(d) A CO2 span gas that meets the specifications of paragraph 9.5.1. and a concentration that is approximately twice the maximum CO2 concentration expected during emission testing shall be used;
d) On utilise un gaz de calibrage CO2 satisfaisant aux spécifications du paragraphe 9.5.1 et une concentration approximativement double de la concentration de CO2 maximale attendue pendant l &apos; essai d &apos; émissions;