Southeastern Wisconsin has an air quality problem that requires a multi-faceted approach to solve. In order to achieve and maintain the 8-hour ozone air quality standard, the Wisconsin Department of Natural Resources has developed a plan (State Implementation Plan) that requires targeted reductions in volatile organic compounds (VOCs) and nitrogen oxides (NOx) emissions in the Milwaukee area from motor vehicles, industry and other sources. The Wisconsin Vehicle Inspection Program (WIVIP) contributes to this effort by reducing motor vehicle VOC emissions by 7% and NOx emissions by 5%. So far, no other control strategies have been found that could replace the WIVIP test.

Studies are demonstrating that the air pollution from one area where it is produced is likely being transported to another with the prevailing winds. All four states bordering Lake Michigan are working together to find solutions to improve air quality throughout the region.

Unlike other pollutants, ozone is not emitted directly into the air. Rather, it is formed in the presence of sunlight through chemical reactions between nitrogen oxides (NOX) and volatile organic compounds (VOCs). In southeastern Wisconsin, vehicles emit about one-third of these ozone-forming pollutants - which the rest emitted by industry and other smaller sources, such as lawn and garden equipment, paints, motorboats, and some businesses.

While ozone in the upper atmosphere is beneficial to people by shielding the earth from harmful ultraviolet radiation given off by the sun, high concentrations of ozone at ground level are a major health and environmental concern.

Ozone pollution poses a significant health risk, especially for the elderly, young children, and those with respiratory difficulties. In addition, high levels of ozone can damage crops and forests.

The vehicle inspection program identifies vehicles with high hydrocarbon and/or carbon monoxide levels so repairs can be made to reduce harmful emissions.

All vehicles will receive an OBD inspection.  The inspection consists of verifying that the vehicle's check engine light is working and communicating with your vehicle's on-board computer.  On Board Diagnostic testing procedures are detailed here.

A well-maintained vehicle should continue to pass the inspection. Nine out of ten vehicles pass the inspection.

If your vehicle fails, it will need to be repaired and brought back for reinspection. Motorists are provided information to help the repair technician diagnose the cause of the failure. Motorists are also given information so they can review the track records of repair facilities to help them decide on where to take their vehicle for repairs. A list of state recognized repair facilities is also available to help you make decisions about where to have your vehicle repaired.

Registration Renewal Tests:  If your license plates are expiring, you would need to purchase a 30-day temporary license plate.  They can be purchased either by mail, or in person at DMV Customer Service Centers or Wisconsin Vehicle Inspection facility (in the office area).  There is a $3 charge for the temporary plates and an additional counter fee if purchased at either a DMV center or test station.  A vehicle may be eligible for up to 3 temporary plates and some restrictions apply.

Change of Ownership Tests:  If you recently purchased the vehicle and are nearing the end of the 45 day testing window, you would  need to call the following number for a one-time 30 day extension: 1-866-OBD-TEST. There is no charge for this service.  The 30-day extension can not be issued at the vehicle inspection station.

After meeting emission-testing requirements, most motorists can now purchase their vehicle license plate stickers at all emission-testing locations. There is a $10 fee for this registration renewal service and some restrictions apply. Call the test facility for payment options. Please ask the emission inspector for details.

Generally, all passengers and pets will have to exit the vehicle while the inspector is driving it. If it is necessary for you to stay in the vehicle during the inspection, you may move out of the driver's position to another seat in the car while the inspector tests your vehicle. If you have a specific concern, please see the station manager.

Please complete an application for temporary exemption from the testing requirement until the vehicle is back in the area.  The exemption form is MV2472 and instructions are on the form.

Vehicles subject to emissions inspection may fulfill the inspection requirement up to 180 days prior to their license plate renewal date.  You can determine whether your vehicle is due for inspection within the next 180 days by entering your license plate on WisDOT's plate inquiry page .  If the inquiry result page includes the statement "IM test is needed," your vehicle's plate renewal date falls within the next 180 days.  You do not need a renewal statement in order to receive your inspection- simply visit the station registration desk, located within the office area, prior to getting in line for an inspection.

Vehicles more than five model years old are required to be inspected upon change of ownership. Motorists receive notice of the emission-testing requirement after they have titled and registered the vehicle. Failure to complete the emission requirement within the allotted 45-day time period will result in the suspension of the newly purchased vehicle's registration.

All program questions can be directed to 1-866-OBD-TEST.