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Emissions Testing Is Essential

The quality of the air we breathe is more important than ever. All Arizonans deserve the cleanest possible air today and for our future — especially those with compromised health. We all can make a positive difference by the choices we make and actions we take everyday. Vehicle emissions contribute to increased levels of air pollution like man-made ozone and particulate matter (smoke and dust). And, for the millions of Arizonans who choose to own and operate motor vehicles, each plays an important role in maintaining and improving Arizona’s air quality by simply testing vehicle emissions to ensure they meet health-based standards.

As critical as the quality of air for our communities, is the health and safety of our community and customers we serve and our employees. To continue to provide exceptional service that protects public health, ADEQ has made key changes that put the health and safety of both customers and staff first as we work together to do our part for each other. ADEQ’s changes provide as safe of an emissions testing experience as possible — one that goes above and beyond CDC guidance for other essential services like grocery stores, gas stations, and drive throughs.

Why Emissions Testing is Required

Vehicle emissions testing is required in major metropolitan areas that are not meeting federal air quality standards for ozone and other pollutants. In Arizona, testing is required in the Phoenix and Tucson metropolitan areas. The American Lung Association’s State of the Air 2021 report ranked the Phoenix metropolitan area the 5th most polluted in the country for ozone and the 8th most polluted for small particulate matter (PM2.5). The Phoenix and Tucson areas both received an "F" for ozone pollution. The Phoenix area also received a failing grade for small particulate matter pollution. Particulate matter pollution is made up of tiny pieces of solids or liquids suspended in the air. Vehicles contribute to this type of pollution, as well as ozone pollution.

ADEQ press release for American Lung Association State of the Air 2021 report | View >

Why Ozone and Particulate Matter Pollution is a Problem

Ozone and particulate matter pollution exacerbates breathing-related illnesses such as bronchitis, emphysema, asthma, chronic obstructive pulmonary disorder (COPD), and other respiratory or pulmonary issues. The science linking ozone and particulate matter pollution to negative health effects is extensive, and some researchers estimate that 50,000 premature deaths occur in North America every year because of ozone. A Harvard study found long-term exposure to small particulate matter pollution can increase the COVID-19 death rate. And, a university in Germany found 78 percent of deaths related to COVID-19 were in the study areas with the highest levels of nitrogen dioxide, which is produced by vehicles and contributes to man-made ozone pollution. Researchers in both studies concluded that long-term exposure to bad air quality is an important contributor to COVID-19 death, underscoring the importance of continuing efforts to maintain and improve air quality.

It is important to note that while there are several ways to avoid viruses, there are few ways to avoid poor air quality. Unfortunately, and to compound matters, our historically high ozone season is April through October.

Additional resources:

  • PHYS ORG: One Million Premature Deaths Linked to Ozone Air Pollution | View Page >
  • Harvard Study:  Exposure to air pollution and COVID-19 mortality in the United States | View/Download >
  • Martin-Luther University Halle-Wittenberg (Germany): Assessing nitrogen dioxide (NO2) levels as a contributing factor to coronavirus (COVID-19) fatality | View >
  • American Lung Association: Ozone | View Page >
  • EPA: Health Effects of Ozone Pollution | View Page >
  • CDC: Particulate Matter Pollution | View Page >

ADEQ is Providing the Safest Vehicle Emissions Testing Experience Possible to Protect Customer and Employee Health and Safety

To keep everyone safe as we work together to protect air quality, our vehicle emissions testing technicians have put enhanced health and safety protocols in place to protect public health and our customers and staff.

Enhanced Health and Safety Practices | Watch Video > 

  • Technicians testing vehicles are wearing masks
  • Technicians are washing their gloved hands with a chlorine and water solution between each vehicle emissions test
  • Emissions test inspectors maintain social distancing protocols when possible
  • During the vehicle inspection, customers have have 3 options for where to wait:
    • A waiting booth, which is sanitized 4 times per day
    • A waiting area
    • Outside the station building (sitting on the passenger side of the vehicle while the technician is working is no longer permitted)
  • Customers are asked to insert and remove their credit cards into credit card readers for payment

What to Expect When You Come to Test Your Vehicle Emissions -- Enhanced Procedures to Protect Your Health and Safety:

  • Pull your car into the station, put it in park and apply your emergency brake. If your vehicle is a manual transmission, ensure you put it in neutral
  • Choose where you are most comfortable waiting for test to be completed: the waiting booth, waiting area or outside
  • While you are waiting the inspector performs the On-Board Diagnostic (OBD) test — without getting into your vehicle — the inspector reaches in to connect the OBD cord to the data link connector (DLC)
  • Once that is complete, you will be asked to return to your vehicle to turn the ignition key to the accessory position, so the inspector can verify the check engine light is functioning
  • You will then start your vehicle, allowing the inspector to observe that the check engine light turns off from a safe distance
  • After the OBD test is complete, you will turn off the vehicle and exit to the waiting area of your choice (waiting booth, waiting area or outside)
  • When payment is due, simply insert your credit card and remove when processing is complete
  • You then return to your vehicle, and the inspector finishes the test process and delivers your vehicle information report, all while maintaining social distancing

To provide customers with an alternate choice, ADEQ can provide No-Contact and Limited Contact Emissions Tests | Learn More  >

ADEQ will continue to improve and refine testing for our customers as opportunities arise.