6. Trends in NOx Emission Performance of the Canadian Fleet

• 6.1 Distribution of Bins
• 6.2 Fleet Average NO_xValues

The changing distribution of LDV/LLDT and HLDT/MDPV by NO_x standard (bin) across the 2004 to 2006 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 and then to over 85% for the 2006 model year. The distribution of the HLDT/MDPV certified to bin 5 or better increased slightly from less than 1% in the 2004-2005 model years to 9% in the 2006 model year. However it should be recognized that, whereas LDV/LLDT fleets are subject to the 0.07 grams/mile fleet average NOx standard beginning with the 2007 model year, the phase-in period leading to the final combined fleet average NOx standard of 0.07 grams/mile extends over the 2004 to 2008 model years for HLDT/MDPV fleets. Beginning with the 2009 model year, the combined LDV/LLDT and HLDT/MDPV fleets will be subject to the 0.07 grams/mile fleet average NOx standard.

Figure 3 compares the average NO_x values achieved for the 2006 model year with those of the 2004 and 2005 model years.

As shown in the figure, the average NO_x value for the fleet of LDV/LLDT continued to decline by approximately the same percentage as the applicable fleet average NO_x standard over the 2004 to 2006 model years. The average NO_x value for the fleet of HLDT/MDPV declined by 23% between the 2005 and 2006 model years, after having risen slightly between the 2004 and 2005 model years. The average NO_x values for both fleets remain below their respective standards by at least 21%.