For decades now, the United States has been quite invested in emissions testing on vehicles. Clean air with less pollutants have been a top priority, and as a result, emissions control is a common thing to see before registration or during annual safety inspection in many states.
Diesel vehicles in particular have been prone to riding the line of legality. That's why diesel emissions testing programs are more strict, but even gas-powered motor vehicles are subject to inspection. In many cases, new vehicles made in the last five years and electric vehicles are exempt.
Certain states have particular test cycle requirements that vehicle owners must abide by. Failing to do so will result in the DMV denying the registration of the vehicle. Since each state is a little different, let's check out the 33 states that require this emission testing.
States That Require Emissions Testing
1. Alaska -- Every two years in Fairbanks and Anchorage.
2. Arizona -- Required prior to vehicle registration.
3. California -- Required for all gas vehicle made after 1976 and diesel vehicles made after 1996. Certain areas subject to smog inspection.
4. Colorado -- Required for registration, re-registering, or selling a vehicle.
5. Connecticut -- All vehicles after 1968 must have effective air pollution control system. Inspection is bi-annually.
6. Delaware -- Required for all vehicles made after 1968, with the exception of newer model year vehicles made in the last five years.
7. Georgia -- Subject to yearly vehicle emissions inspection.
8. Idaho -- Required in Ada and Canyon counties.
9. Illinois -- Dependent on year of vehicle. Annual testing required in numerous counties.
10. Indiana -- Varies from county to county.
11. Kentucky -- Required in certain cities.
12. Louisiana -- Emission testing included in safety inspection.
13. Maine -- Required for original registration or annual registration renewal in Cumberland County.
14. Maryland -- Exhaust emission test and misfueling inspection every two years.
15. Massachusetts -- Safety and emissions test required annually for passenger cars after 1997.
16. Missouri -- Required biannually in many counties.
17. Nevada -- Automotive vehicles located in urban areas of Clark and Washoe Counties are subject to testing.
18. New Hampshire -- 1996 and newer model years must have onboard diagnostic system that meet EPA standard.
19. New Jersey -- Typically calls for annual emissions inspection.
20. New Mexico -- Albuquerque and Bernalillo County require testing.
21. New York -- Annual emissions standards testing.
22. North Carolina -- Required in 22 counties for 1996 or newer year models, or if the vehicle has more than 70,000 miles.
23. Ohio -- Emissions test required biannually.
24. Oregon -- Vehicles after 1975 subject to emission inspection at Portland Vehicle Inspection station.
25. Pennsylvania -- Periodic emission inspections with some exemptions.
26. Rhode Island -- Biannual emission inspection.
27. Tennessee -- Must pass emission inspection prior to registration renewal.
28. Texas -- Emission inspection required prior to registration.
29. Utah -- Annual emission testing, with newer vehicles being exempt.
30. Vermont -- Dealerships must sell the cleanest cars to residents following California's Low Emission Vehicle Program.
31. Virginia -- Vehicles with a gross vehicle weight rating (GVWR) under 10,000 pounds must have emission inspection done biannually. There are some exceptions.
32. Washington -- Vehicles between five and 25 years old required to pass inspection every two years.
33. Wisconsin -- Must pass emissions inspection no more than 90 days prior to renewal of registration, and every two years.