Check to see you have a gas cap in place. This is required equipment. It must be the correct type for your vehicle, and it must have a tight seal. A missing or leaky gas cap will cause your vehicle to fail the test.

Follow recommended maintenance schedules for your vehicle. Read your owner's manual, and follow maintenance guidelines. Your vehicle will perform more efficiently.

Don't overfill your gas tank. When filling your tank, resist the impulse to get just a little bit more into the tank after the nozzle clicks off. This excess gasoline has nowhere to expand so it saturates a part of the emissions control system resulting in increased emissions.

Your vehicle's emissions control equipment must be intact and functioning. Missing or tampered emissions control equipment will cause your vehicle to fail the test.

Make sure your tires are properly inflated. Tires that are unevenly inflated, under-inflated or mismatched make the vehicle difficult to test on the dynamometer, and may cause the vehicle to be rejected from testing.

Fully warm up your vehicle before testing. Until your vehicle is at normal operating temperature, it emits excess pollution. Run your vehicle at highway speed for at least 15 minutes prior to undergoing an emissions test. Limit use of air conditioning and defroster if possible.

Make sure your brakes are in good condition. Poor brakes can make the vehicle difficult to test on the dynamometer, and may cause the vehicle to be rejected from testing.

Front-wheel drive vehicles: Make sure the front suspension is properly aligned. Poor front-end alignment will make the vehicle difficult to test on the dynamometer, and may cause the vehicle to be rejected from testing.

Ensure the integrity of your exhaust system. Excessive exhaust leaks can cause your vehicle to be rejected from testing. Exhaust leaks are also dangerous to the vehicle's occupants.

Make sure your vehicle does not smoke. Visible smoke is a sure sign of excess pollution and will cause your vehicle to fail the test.

Emission Testing Station Locations

The program area for the enhanced emissions testing program includes the counties of Adams, Arapahoe, Boulder, Denver, Douglas, Broomfield and Jefferson, with the exception of the rural portions of Adams and Arapahoe counties east of Kiowa Creek. Beginning in 2010 parts of Larimer and Weld counties were added to the enhanced program area.

The 18 Envirotest-operated emissions testing centers perform both the enhanced I/M 240 test for 1982 and newer vehicles, and the two-speed idle test for 1981 and older vehicles. 1981 and older vehicles may also be tested at an independent test center. For information on locations of these centers, call 303-692-3270. For information on emissions testing for diesel-powered vehicles, call 303-205-5603 or 303-744-2442.

Click on the station links for physical address, hotline number, hours and other information.

NOTE ABOUT THE MAP FOR THE LONGMONT STATION:
The Google Map is incorrect. Please use the following written directions to find our Longmont location.

FROM BOULDER: Go north on Foothills Pkwy to the Diagonal Hwy (119). Take the Diagonal northeast to 87th Street. Turn left (north) on 87th. It becomes Airport Rd after crossing Nelson Rd. Station is at the northwest corner of Airport Rd and Rogers Rd.

FROM Interstate 25: From I-25 northbound, take Exit 240 (Hwy 119). Go west on 119, across the railroad tracks, to Nelson Rd. Turn right on Nelson to Airport Blvd. Turn right on Airport to Rogers Rd (2nd left) and turn left on Rogers. The station is at the northwest corner of Airport and Rogers Rd.

Wait Time Note:
Please keep in mind that the wait times include an average test time of 20 minutes, so if the wait time for a station says "30 minutes," the actual wait prior to the test is about 10 minutes. The wait times are updated approximately every 15 minutes.

Emission Testing Station Locations

Wait Time Note:Please keep in mind that the wait times include an average test time of 20 minutes, so if the wait time for a station says "30 minutes," the actual wait prior to the test is about 10 minutes. The wait times are updated approximately every 15 minutes.

Wait Time Note:
Please keep in mind that the wait times include an average test time of 20 minutes, so if the wait time for a station says "30 minutes," the actual wait prior to the test is about 10 minutes. The wait times are updated approximately every 15 minutes.