Emissions Testing in Utah

Testing Requirements

Current Testing Requirements in Utah

Utah operates emissions testing programs in five counties: Cache, Davis, Salt Lake, Utah, and Weber. Each county's program is administered by its local health department under state statute (Utah Code 41-6a-1642). For 1996 and newer gasoline vehicles, the test is an OBD-II diagnostic scan. Older vehicles within the testing window may receive a tailpipe test. A gas cap test and visual inspection of emissions components are also performed. Utah does not require periodic safety inspections for most private passenger vehicles. The emissions test is performed at certified I/M stations, identifiable by blue and white signs, located at auto shops, dealerships, and service stations throughout the five counties. Many stations participate in the On The SPOT (OTS) program, allowing drivers to test and renew registration in a single visit.

Who Needs an Emissions Test

Gasoline-powered vehicles registered in Cache, Davis, Salt Lake, Utah, or Weber counties must pass an emissions test. The specific model year requirements vary by county. In Davis, Salt Lake, Utah, and Weber counties, vehicles under six model years old are tested biennially. Vehicles six years old and older (model year 1968 and newer) are generally tested annually. In Cache County, vehicles under six years old are exempt, and vehicles six years and older are tested biennially. Diesel vehicles under 14,000 pounds are subject to testing in some counties (requirements vary). Gasoline vehicles over 14,000 pounds with model year 2008 and newer, and gasoline vehicles over 8,500 pounds with model year 2007 and older, are exempt. Motorcycles are exempt. Electric vehicles are exempt. Vehicles model year 1967 and older are exempt in Davis, Salt Lake, Utah, and Weber counties. Vehicles model year 1968 and older are exempt in Cache County. Farm vehicles may qualify for exemptions in some counties.

How Often Tests Are Required

Testing frequency varies by county and vehicle age. In Davis, Salt Lake, Utah, and Weber counties, vehicles under six model years old are tested biennially on an odd/even model year cycle. Vehicles six years old and older are generally tested annually. In Cache County, vehicles under six years old are exempt, and vehicles six years and older are tested biennially on the odd/even cycle. Emissions certificates must be current at the time of registration renewal. Certificates cannot be obtained more than two months before registration renewal.

Where Emissions Testing Is Required

Emissions testing is required in five counties: Cache (Logan area), Davis (Clearfield, Bountiful, Layton area), Salt Lake (Salt Lake City metro), Utah (Provo, Orem area), and Weber (Ogden area). Vehicles registered in all other Utah counties are not required to pass an emissions test. Out-of-state emissions certificates are not accepted for Utah registration.

What Happens During the Test

For 1996 and newer vehicles, a technician connects to the OBD-II port and checks for stored diagnostic trouble codes, readiness monitor status, and the malfunction indicator lamp. A lit check engine light causes automatic failure. A gas cap test checks for fuel system leaks. A visual inspection confirms the presence of the catalytic converter and other emissions control components. For older vehicles, a tailpipe test may measure exhaust pollutants. The test typically takes 10 to 15 minutes. If the vehicle passes at an OTS station, registration can be renewed immediately on site.

Areas in Utah That Require Emissions Testing

Within the five covered counties, cities and communities where testing is required include Salt Lake City, West Valley City, West Jordan, Sandy, Orem, Provo, Ogden, Layton, Logan, Clearfield, Bountiful, Murray, Draper, Riverton, Taylorsville, South Jordan, Lehi, American Fork, Pleasant Grove, Springville, Roy, North Ogden, Kaysville, and Brigham City (if in Cache or Box Elder emissions zone). Cities outside the five counties do not require emissions testing. St. George, Cedar City, Moab, Vernal, Price, Richfield, Tooele (if not in a covered county), and all rural Utah communities are exempt.

How the Emissions Test Works in Utah

Drivers take their vehicle to any certified I/M station in their county. These are private auto shops, dealerships, and service stations displaying the blue and white emissions sign. No appointment is needed at most stations. Bring your vehicle registration. Fees vary by county. Cache County caps fees at $20. Weber County caps fees at $30 (or $35 per some sources). Davis, Salt Lake, and Utah counties allow stations to set their own fees, with averages around $25 to $55. A small county emissions fee ($1 to $3) is also added at registration. If the vehicle passes, results are transmitted electronically and registration can be renewed. If the vehicle fails, the owner must complete repairs and return for retesting. Contact the county health department for information on waivers if the vehicle continues to fail after repairs. The AERAP-equivalent repair assistance programs vary by county. The Utah DMV at dmv.utah.gov lists county health department contacts for each emissions program.