Smog & Emission Checks

More than 35 years ago it became obvious to some agencies that the number of vehicles on the road would increase; an expanding economy reliant on truck traffic to move goods across America was also heating up, and the Environmental Protection Agency (EPA) passed the Clean Air Act of 1970.

What does the Clean Air Act of 1970 have to do with your car? Well, engine and exhaust emissions are considered air pollutants. But don't worry, after many decades of research and development the car makers and government agencies have developed systems to control and test for exhaust emissions.

Delaware has a reason to be concerned with air pollution; Delaware and 34 other states exceed the federal health standard for air pollution. The Department of Natural Resources and Environmental Control (DNREC) sets the limits on emissions for cars and trucks in Delaware. However, it is only logical for the Division of Motor Vehicles (DMV) to test for and enforce the standards.

When you bring your car in for inspection, which is part of the registration process, your vehicle will be tested for emissions. There are two major types of polluting emissions―exhaust and evaporative. You can learn more about emissions and air pollution at the EPA Web site.

You must pass the emission test to register or renew registration on your vehicle. The test you are given depends on the age of your car.

1996 and Newer

By 1996 the auto makers had developed a sophisticated On Board Diagnostics Test (OBD II) to monitor and measure emissions failures. Your car's computer will send a signal to you when you have a failure in your exhaust or engine system that could increase your emissions.

Usually, the Malfunction Indicator Lamp (MIL) will come on if you have an exhaust leak or a fuel leak in your engine. In fact, some cars' check engine light, a common MIL signal, will come on if the gas cap isn't clamped on tightly.

The DMV inspection technician will check your dashboard for any warning lamps. A cable will be connected to your car's computer to detect any emissions failures and the MIL will be tested for proper functioning.

Model Years 1980 to 1996

The inspection technician will select the proper test based on the year of your vehicle. If your car is newer than 1980 but older than 1996, you will be given the low/high speed emissions test―two-speed idle.

The technician is looking for signs of exhaust failure or engine emissions. The standards are specifically geared to the limitations of your vehicle; meaning if your engine meets all manufacturer specifications then you will probably pass the emissions test.

Model Years 1968 to 1980

The test for this older group of vehicles is not as stringent because the engineering at the time of manufacturer was so different regarding emissions. Primarily, the test will look for exhaust leaks, blowing smoke, smoke from the engine while the car is idling.

Model Years Older Than 1968

Some cars were designed and produced before emissions were a concern. In all fairness to the car owner, the DMV and the DNREC only expect these vehicles to function as best they can within the constraints of the original manufactured design.

Your 1968 or older model car won't be tested for emissions. But still, any efforts you make to improve air polluting emissions on older model cars will help the air pollution efforts of Delaware and the EPA. As a resident of Delaware you too are probably concerned with air quality.

Failing the Emissions Test

If your car doesn't pass the emissions test, first be sure you were held to the right standard based on your model year. The categories are broad so chances are you were tested properly.

You can get a recheck, free of charge, once you make the proper repairs. A reputable mechanic or repair technician should be able to fix your car so it passes the emissions check. Keep your receipts because if you spend over the maximum limit, you may be eligible for a waiver if you can prove your expenses.

The limit you spend before getting a waiver depends on the year of your car and the county you live in. Cars in the 1968 to 1980 range have a set maximum spend of $75; if you exceed the $75 apply for a waiver at the DMV office.

Newer vehicles, 1981 to present, require a larger spend before you can get the waiver. In New Castle or Kent County you must spend $738. Sussex County only requires a $200 repair limit. If you do the repairs yourself you can only count the parts towards the spending limit.

Waivers and Extensions

Delaware does not offer waivers for safety-related items, like bad tires, brakes, a faulty exhaust system, or anything that makes your car unsafe. You might be eligible for a 30-day temporary tag or a 15-day temporary permit to make these types of repairs.

Only a one-time extension is allowed, for no more than 30 days, if the vehicle fails the testing before the registration ends.

The DMV might grant a waiver for cars whose owners have spent a certain amount on repairs but the vehicle still will not pass the testing. Refer to the state's vehicle inspection FAQs for more information about how to qualify for an emissions waiver and how to get one.

Reporting Gross Polluters

Delaware offers a 24-hour complaint line for residents to report polluters. This line is used for all types of pollution, from industrial and corporate to the individual. It is also used to report emergencies and for emergency preparedness. Call (800) 662-8802.

Emissions checks are important and the DMV completes more than 400,000 checks every year. It is nice to know that drivers, car manufacturers, repair technicians, and government agencies are all working to improve the air we breathe.