6. Trends in NOx Emission Performance of the Canadian Fleet

• 6.1 Distribution of Bins
• 6.2 Fleet Average NO_x Values

The changing distribution of LDV/LLDT and HLDT/MDPV by NO_x standard (bin) across the 2004 to 2005 model years is depicted in figures 1 and 2, respectively.

The percentage of LDV/LLDT certified to bin 5 -- which effectively represents the final phased-in fleet average NO_x standard of 0.07 grams/mile -- or better increased from 37% for the 2004 model year to 62% for the 2005 model year, while the distribution of the HLDT/MDPV fleet remained relatively similar. However, HLDT/MDPV fleets are only required to meet the final phased-in fleet average NO_x standard of 0.07 grams/mile in the 2009 model year, compared to the 2007 model year for the fleets of LDV/LLDT.

Figure 3 compares the average NO_x values achieved for the 2005 model year with those of the 2004 model year.

As shown in the figure, the average NO_x value for the fleet of 2005 model year LDV/LLDT was reduced by about the same percentage as the applicable fleet average NO_x standard, compared to the 2004 model year. However, the average NO_x value for the fleet of HLDT/MDPV remained relatively unchanged. Nonetheless the average NO_x values for both fleets remain below their respective standards by at least 22%.