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Automobile Emissions Testing

Emissions Testing Station locations, wait times, and other up-to-date information is available through the State of Colorado's vehicle emissions testing contractor:


The Automobile Inspection and Readjustment (AIR) Program's purpose is to reduce motor vehicle related pollution through the inspection and emissions-related repair of gasoline powered motor vehicles.


Emissions testing of gas and diesel powered vehicles is required when registering, renewing registrations, or selling vehicles within the program areas in nine counties along Colorado's Front Range.


The current AIR Program covers the nine-county Front Range area, including all or portions of Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas, Jefferson, Larimer, and Weld counties.


The RapidScreen program provides an opportunity for vehicles to forego testing if they are found to meet emissions standards after driving by a roadside monitor.


1982 and Newer Vehicles:

An enhanced test is required for gasoline powered passenger cars and light trucks 1982 and newer in the seven-county Denver metro area, which includes the counties of Broomfield, Denver, Jefferson, Boulder, Douglas, and western Arapahoe and Adams counties (west of Kiowa Creek). New cars are exempt from testing to the original owner for four years. The enhanced inspection is performed at any one of 14 inspection stations operated by AirCare Colorado. The inspection utilizes a dynamometer which simulates actual driving conditions. The test is good for two years. Motorists are alerted to the need for a test by a notice on their registration renewal forms.




Older than 1982:

A basic two-speed idle test is required each year for vehicles older than 1982 and heavy trucks in the six-county Denver metro area. The basic test can be performed at Air Care Colorado facilities, or at an independent, licensed test station.



The Enhanced Vehicle Emissions test expanded from the Denver area to parts of Larimer and Weld Counties in November of 2010 to control ground-level ozone. The Air Pollution Control Division made the following presentation during the public hearing that provides the regulatory and scientific basis for expanding the program to the north Front Range.



The basic two-speed idle gasoline test emissions program in El Paso County was discontinued on January 1, 2007, based on long-term compliance with the carbon monoxide standards.


Changes to Vehicle Emissions Testing Coming in 2015

Changes are effective January 2, 2015:
  • Exemptions for new vehicles will increase from four to seven model years
    A model year 2010 vehicle, for example, would not need any emissions tests until 2018.
  • Vehicles that are 8 to eleven 11 years old will only need a test of their on-board diagnostic (OBD) computer systems
    2005 through 2008 vehicles would get an OBD test in 2018.
    Learn more at www.epa.gov/obd or www.obdclearinghouse.com.
  • Vehicles that are 12 years and older will still get the “I/M 240” dynamometer (treadmill) test
    I/M 240 is still the most comprehensive way to test vehicle emissions under real-world conditions.
  • Hybrid vehicles that are 12 years and older will now require emissions testing
    The program will now test any vehicle with a gas cap to verify that it is still running clean.
  • Vehicles with their “Check Engine” light turned on will now need repairs in order to pass the emissions test
    Making these repairs can improve your vehicle’s performance, make it last longer, and save you money.
  • You can still pass the emissions test through the RapidScreen roadside emissions testing program
    1982 and newer gasoline-powered vehicles that are well-maintained and low-polluting can skip a trip to an emissions testing station.
    Drive past at least two different RapidScreen roadside emissions testing units on at least two different days between 12 and two months before your vehicle’s registration renewal date. If “Passed Roadside Emissions” appears on your registration renewal card (which arrives in the mail about two months before your renewal date), then you do not need to also go to an emissions testing station.
    In addition to the white and blue vans you’ve already seen on the roadside, RapidScreen will now also use small green remote sensing units. These units use the same state-of-the-art technology as the vans, allowing you to pass your emissions test while driving.
  • No increase in testing fees!
    Colorado’s emissions testing fees have stayed the same for nearly 20 years, and they will continue to stay the same even with these changes.
  • Air Care Colorado emissions testing stations will now accept cash, checks, and credit cards!
    They will accept Visa, MasterCard, Discover, and possibly others in the future.