Motor Vehicle Emission Reductions & Air Quality Improvement

Reducing motor vehicle emissions plays a large role in improving regional air quality.  Along with reformulated gasoline use, the WVIP is Wisconsin’s most significant vehicle emission reduction program, and one that contributes to improved air quality in the entire upper Midwest.

The DNR estimates that the program achieved the following reductions in on-road motor vehicle emissions during 2006:

• Volatile organic compounds (VOC) emissions by 5.1 tons per summer weekday, or 12.0%.

• Oxides of nitrogen (NOx) emissions reduced by 6.8 tons per summer weekday, or 7.3%.

• Carbon monoxide (CO) emissions reduced by 80.5 tons per summer weekday, or 14.8%.

Interpolated Hot Summer Weekday Emissions (tons)

Over time, the WVIP has contributed to the following air quality advances in Wisconsin:

• Ozone: Ground-level ozone concentrations in southeastern Wisconsin have dropped significantly over the past 15 years.  During 1990 the 1-hour ozone “design value” (a calculated measurement used to evaluate compliance with the 1‑hour ozone standard) for southeastern Wisconsin was 0.19 parts per million (ppm).  This value was high enough that six southeastern Wisconsin counties were classified as a severe ozone nonattainment area under the 1990 Clean Air Act amendments.  Other eastern Wisconsin counties were assigned less severe non-attainment designations.

By 2001, the 1-hour design value for southeastern Wisconsin had dropped to 0.12 ppm, meeting the 1-hour ozone standard.  All Wisconsin counties are now considered in attainment for the standard.  2000 was the first year of ozone monitoring where the 1-hour ozone standard was not exceeded in southeastern Wisconsin.

More recently, the U.S. EPA implemented a more stringent ozone standard, the so-called 8-hour ozone standard.  In April 2004, several southeastern and eastern Wisconsin counties were designated non-attainment areas under this standard.  The WVIP will play an important, ongoing role in the state’s efforts to comply with the standard.

• Carbon Monoxide:  Between 1977 and 1984, southeastern Wisconsin exceeded the federal carbon monoxide standard 35 times.  Since the program’s implementation in 1984, southeastern Wisconsin has not exceeded this standard even once. 

Credit for these air quality improvements goes to various state and federal ozone control measures implemented both in Wisconsin and other states.  Aside from Wisconsin’s and neighboring states’ vehicle inspection and maintenance programs, these include reformulated gasoline, national emission standards for new motor vehicles, utility and industrial source controls, and gasoline vapor recovery controls.

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Additional Services

Technical Assistance Centers

When a vehicle is repaired at a shop with emission-trained technicians and still fails a retest, the motorist may take it to one of two program-operated Technical Assistance Centers (TACs).  Appointments are made through the emission testing facilities. During 2006, 1,043 motorists received technical assistance center service.  This compares to 1,014 appointments in 2005. 

The TACs are staffed by master technicians who can assist in identifying the causes of excessive vehicle emissions.  While the master technicians provide free vehicle diagnostic services, they do no repair work.  They share diagnostic analysis results with the motorist, who may pass them on to a hired repair technician.  Additional repairs can then be performed and the vehicle returned to a station for retest.

Registration Renewal and Titling Services

Motorists now may renew their license plates or complete titling transactions at any vehicle test station.  Registration renewal/titling offices, located at all 12 of the testing locations, are open during all 54 testing hours per week, including Saturdays from 8 am – 1 pm.  An additional service fee is charged for conducting these transactions performed at a test station.  Stations processed 281,500 registration renewals in 2006 and processed 270,906 in 2005. 

Emission test stations also perform titling services.  In 2006, stations completed 9,132 titling transactions, compared to 7,387 in 2005.  The increase occurred largely because titling services are becoming more publicized throughout the community.

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