1. COMMENT: The commentor indicated that he is opposed to the extension of the new 

vehicle inspection exemption from four (4) years to five (5) years but willing to work 

with the Motor Vehicle Commission (MVC) on a smooth transition and further changes 

that will benefit the State budget, the public and small businesses. The commentor 

believes that if the new vehicle inspection exemption period is extended, the time period 

when the motorist will ignore an illuminated Check Engine light will be extended from 4 

to 5 years, polluting the air for an additional year.

RESPONSE: The Department evaluated the emission reduction impacts of the proposed 

extension of the new vehicle inspection exemption period using the protocol set forth in 

the USEPA’s final rule on I/M requirements. The USEPA protocol requires a 

demonstration, using the most current version of USEPA’s mobile source emission 

model, that the equivalency of the emission levels achieved by the State’s proposed 

enhanced I/M program design be compared to those of the performance standard. Using 

this protocol, the results of the model indicate that there is no difference between 

emission factors for New Jersey’s existing and proposed enhanced I/M programs for 

ozone precursors (VOCs and NOx). For these pollutants the magnitude of the increase in 

emissions due to the increased new vehicle exemption period from 4 years to 5 years is 

completely offset by the reduction in emissions due to the increased effectiveness of New 

Jersey’s Private Inspection Facilities (PIFs).

The new enhanced I/M program design results in an insignificantly small increase in the

predicted carbon monoxide emission factor relative to the existing enhanced I/M

program. The increase is well below the USEPA margin of error of +/- 0.02 grams per 

mile (gpm). When stated to 4 significant figures, the carbon monoxide emission factors 

are the same. 

This demonstrates that the proposed changes to the enhanced I/M program do not 

compromise the State’s efforts to meet and/or maintain National Ambient Air Quality

Standards (NAAQSs) for ozone or carbon monoxide. Also, the State's new enhanced I/M 

program meets the USEPA low enhanced performance standard.

The Department appreciates the commentor’s willingness to work with the State on 

making a smooth transition into the new I/M program. The Department is also 

committed to working with the PIFs, the MVC and other State agencies to ensure that 

changes to the inspection program continue to protect the health of New Jersey’s citizens 

and its environment. 

2. COMMENT: The commentor supports upgrading the Private Inspection Facility (PIF) 

inspection effectiveness. However, he notes that PIFs should receive 100% equivalency, 

and not limit it to 96% as proposed in the SIP revision. The basis for the commentor’s 

claim is that it is in the best interest of PIF inspectors to identify and point out vehicle 

defects to their customers. 

RESPONSE: The Department commissioned a study to reevaluate the level of PIF 

effectiveness. The study arrived at a factor of 96% PIF inspection equivalency for 
emissions testing. The study compared Centralized Inspection Facility (CIF) and PIF 

inspections, assigning a default of 100% credit to CIF inspections. Among the factors 

examined, the study looked at emission inspection failure rates and suspected incorrect 

emission testing rates for both on-board diagnostics (OBD) and tailpipe tests. The study’s 

findings support the commentor’s assertions that the PIF OBD tests should receive 100% 

credit. Results from tailpipe testing, however, are less conclusive and the Department 

agrees with the study’s conclusions that it is prudent to retain the previous estimate of 

80% effectiveness. The overall 96% PIF credit results from a weighted blending of 100% 

PIF credit for OBD and 80% PIF credit for tailpipe tests. Since an increasing percentage 

of tests are now OBD and not tailpipe, the OBD effectiveness dominates the weighting.

3. COMMENT: The commentor feels that the use of OBD effectiveness in supporting 

lower rates of in-use deterioration in emissions performance may be flawed. The 

commentor further contends that motorists do not always respond to the OBD 

malfunction light and may refuse needed emission repairs if their vehicle is not exhibiting 

driveability issues and is not due for an I/M test. The commentor goes on to state that the 

problem of ignoring needed repairs may have become even worse in recent years as a 

result of economic concerns reducing money available to motorists for repairs. The 

commentor believes that the State is missing this effect but has no way of calculating it. 

RESPONSE: The rate of motorist response to an illuminated Check Engine light in 

between inspection cycles (off-cycle), is a basic function built into the USEPA emission 

factor model. The Department used the most current version of the model to estimate the 

emissions impact of the proposed changes to the I/M program. The USEPA will make 

changes to the model if key assumptions, such as the motorist’s response rate to an 

illuminated MIL change over time. 

4. COMMENT: The commentor stated that, although aware that the hearing was not 

addressing safety-related inspection issues, the same issue regarding lack of motorist 

response to a Check Engine light applies to safety-related defects. The commenter stated 

that his association members continue to document instances where motorists bring their 

cars in for maintenance and are advised of serious safety issues, and now, without a 

safety-inspection program and the need to have the safety-related item corrected in order 

to pass inspection, they are more frequently ignored by the motorist.

RESPONSE: Legislation signed into law on June 28, 2010, directed the Motor Vehicle 

Commission to end mechanical inspections on August 1, 2010 for non-commercial 

vehicles. The commentor is correct that the NJDEP’s SIP hearing covered only the 

emissions-test related aspects of the I/M program and did not address the mechanical 

inspection program. As such, comments on the mechanical inspection program will not 

be addressed in this document. However, the Department has forwarded the transcripts 

from the SIP hearing to the MVC for their information.