Larimer County residents are required to obtain a certificate of emissions control for vehicles within a designated area of Larimer County. The test is required on:
The registration renewal postcard will say "Emission Test Required", if the vehicle is required to be tested.
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.
Hours: Monday through Friday 8:00 am to 5:30 pm and Saturday 8:00 am to 1:00 pm
Phone: 970-247-8378 or 970-Air-Test
To reduce the number of vehicles requiring a traditional emissions inspection, a RapidScreen Program has been established for northern Colorado and the Denver area. Clean vehicles that pass a drive-by roadside test can forego a trip to the emissions inspection station if they receive a notification in the mail saying they passed RapidScreen. The applicable emissions fee of $25.00 will be added to the registration renewal. The RapidScreen Program utilizes remote sensing to measure emissions as vehicles drive past roadside monitors. The monitors measure emissions and record license plate numbers.
RapidScreen Website, including information on locations.
Diesel emission is required in Larimer County within a designated area of Larimer County. Test requirements are based on the appropriate Gross Vehicle Weight Rating. Related information can be found on the Department of Revenue website at www.colorado.gov or you may call 303-205-5603 or 303-744-2442.
The diesel emission testing facilities can charge up to one-hour of the posted labor rates. There is no set fee.
Heavy-duty and light-duty diesel vehicles are exempt from emissions for the first four model years. After the exemption period, vehicles are required to be tested as instructed in Vehicle Emissions Testing Cycles below.
Light-duty diesels that are 2003 and older are required to have an emissions test every year.
Light-duty diesels that are 2004 and newer are required to have an emissions test every 2 years.
Heavy-duty diesels that are less than 10 model years old are to have an emissions test every 2 years.
Heavy-duty diesels that are more than 10 model years old are to have an emissions test every year.
Top Ten Tips to prepare for Colorado's emissions test.
Frequently asked questions from the Colorado Department of Public Health and Environment
Questions regarding the performance of the emission test or testing standards should be directed to the State Emission Section at (303) 205-5603.