Vehicle emissions testing in Washington DC helps reduce the environmental impact of one of the main causes of air pollution in the District. All types of emissions tests in DC are conducted at one central inspection station.

Although not all DC vehicles require regular smog certification, most need regular checks to identify potential problems before they can damage the environment. Continue reading to learn more about the emissions testing process and how to obtain a waiver, if needed.

Washington DC Emissions and Smog Check Requirements

DC’s Vehicle Emissions Inspection and Maintenance Program (I/M Program) is overseen by the Department of Energy and Environment (DOEE). All gasoline-fueled vehicles with a 10,000-pound gross vehicle weight rating or less, manufactured in 1968 or after must pass an emission test before being granted a vehicle registration or registration renewal.

Because all Washington DC vehicle inspections take place at a central testing station, it is helpful to go online and make an appointment ahead of time. Vehicles with visibly smoking exhaust systems will not receive an emissions inspection, so have any smoke problems repaired before making an appointment for a test.

DC DMV emissions testing is performed in three different ways, to meet the needs of different vehicles. The type of test you will need depends on the age of your vehicle, as stated below.

  • Vehicles dated 1968 through 1983 receive a two-speed idle test during which tailpipe emissions are tested for hydrocarbons (HC), carbon monoxide (CO) and carbon dioxide (CO2). The engine is left idling at 350-1200 RPM (revolutions per minute) then accelerated to between 2200 and 2500 RPM.
  • Vehicles with model years between 1984 and 1995 will have an IM 240 emissions test. This inspection/maintenance tailpipe test lasts 240 seconds, hence the name. The vehicle is put on a treadmill-like device called a dynamometer that simulates actual driving behaviors while the technician collects and analyzes the exhaust gases.
  • Vehicles dated 1996 and newer were made with an On-Board Diagnostic (OBDII) system that tracks the vehicle’s emissions system through the use of computer monitoring. During the test, the technician attaches the emissions inspection analyzer to the OBDII system for data exchange. Codes appear to let the technician know where any repairs are needed.

Note: Senior citizens are given priority in the smog check station walk-in line and should just advance to the front of the line upon arrival.

Smog Check Exemptions in Washington DC

Certain vehicles are exempt from emissions testing in Washington DC. These include the following:

  • Personal vehicles that are new, with a manufacturer’s certificate of origin
  • Personal vehicles with a manufacture date of 1968 or older
  • Diesel, electric or other zero-emission personal vehicles or trailers
  • Motorcycles

Out-of-State Emissions Testing in Washington DC

If you are more than 75 miles away from Washington DC and cannot get back to the District before your emissions sticker expires, you may obtain a vehicle inspection where you are. To meet DC smog certification standards, specifically request an emissions test, or an OBDII test.

The report should be printed on the service station’s letterhead and include your vehicle’s year, make, model, mileage, vehicle identification number (VIN) and license plate number. If the DMV finds the report acceptable, they will update your record with your new smog certification, which will remain valid for two years.

Emissions Waivers in Washington DC

If your vehicle fails to pass a smog test despite having been repaired, you may be eligible for a waiver that permits you to skip DC emission inspections for a period of two years. To qualify, present the failing smog certification report along with emission-related repair bills that total at least $881.

Testing Fees in Washington DC

You do not have to pay a vehicle emissions testing fee at the time of your test. Washington DC smog test fees are built into your vehicle registration fees and are paid when you register or renew your vehicle’s registration.

The cost for a new vehicle inspection sticker on a privately owned vehicle is $10 and is good for four years. After that, you may purchase a 2-year vehicle inspection sticker for a greater fee.

Where to Perform an Emissions Check in Washington DC

As mentioned above, there is only one Washington DC emissions testing center in the entire District. It is located at 1001 Half Street, in the southwest quadrant. The best times to visit the DC smog check station are Thursday and Friday between 8:30 a.m. and 10 a.m. or between 1:30 p.m. and 3 p.m.

Failing a Washington DC Smog and Emissions Test

Occasionally, vehicles fail to pass a smog test in DC. Usually, the inspector is able to help identify the cause for the failure, which can be a simple problem or one that results in a big repair bill. A failed vehicle inspection sticker gives you 20 calendar days to obtain any necessary repairs and have the vehicle tested again.

Each driver is eligible for two free re-inspections during this 20-day period. If a vehicle fails on the third inspection attempt, you will have to pay for it and any subsequent re-tests. If you have any problems or questions regarding a failed emissions test, ask to speak to a resolution coordinator before leaving the testing station.

Last updated on Tuesday, March 10 2020.