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Emissions testing helps Northern Virginia meet Clean Air Act limits

By Megan Wilson

Northern Virginia residents are now breathing the impact of on-road emissions testing on their way to work, to school, and to the movies.

On-road emissions testing technology, which uses remote sensors that gauge a car's emissions as it drives past, is being used to help the region to comply with the Clean Air Act.


A fraction of residents will be offered waivers to forego emissions testing and another will be forced to have their cars repaired.


“It’s the only part of the state that doesn’t meet the air standards,” Richard Olin said from the Virginia Department of Environmental Quality.

The EPA set a time limit on meeting Clean Air Act ozone standards by 1999 in revisions to the act made in 1990 and Northern Virginia had been found to still have excess concentrations of carbon monoxide, hydrocarbons, and nitrogen oxides.

Carbon monoxide is poisonous. Hydrocarbons and nitrogen oxides react with summer heat and sunlight to create ozone, according to Olin, the DEQ coordinator for the on-road emissions testing program.

Ozone leads to respiratory problems in people of all ages, according to EPA data. The EPA has found that motor vehicles are the highest contributors to levels of ozone and carbon monoxide in the environment.

Virginia DEQ officials have a contract with Environmental Systems Products and are now using the company’s AccuScan® Remote Sensing device to reduce ozone and pollution levels. 

The Commonwealth was at risk of losing billions of dollars of federal transportation funding for the future, says Virginia Delegate Joe T. May.  He said government officials were even considering outlawing charcoal grills and lawn mowers.

In 1996, DEQ officials and state representatives began looking into devices and other methods to lower pollution levels in Northern Virginia.  Delegate May, who is also an electrician, heard about a device being tested in Springfield, Virginia.

“I ended up spending two hours in a van figuring out this technology,” he said.  “I realized, hey, we really had something here that we could use to help reduce ozone.”


The device projects an infrared and ultraviolet beam of light across the road.  It shoots through the exhaust plume of a car driving by at 20-35 miles per hour. The light also triggers a camera to take a picture of the license plate, Olin said.


A mirror on the other side reflects the light back.  Certain wavelengths are blocked by certain pollutants in the air, Olin said, and through hundreds of equations the data from the reflected light is analyzed by computers in the van.

This information determines vehicles to be either “gross polluters,” “clean screens,” or somewhere in between said Olin. A gross polluter is a vehicle emitting well over the acceptable concentrations of pollutants and the clean screens are well under that limit making the grey area fairly large at this point.


So far, 50 vehicles have received high emitter notices.  Thirty four have received clean screen passes, said Olin.He said they are taking it slowly to make sure cars are actually dirty. They don’t have enough data to make any conclusions about particular vehicle emissions patterns.


According to Staasi Heropoulos, corporate public relations director for ESP, Texas officials are using the same device to strictly track gross emitters in order to issue them notices to have their cars fixed.  Colorado and Missouri officials are using the device to track only clean vehicles.


Virginia is the first to make use of the device to track both clean vehicles and gross emitters; Heropoulos refers to it as a “hybrid program.”  This, he said, is the most efficient use of the technology.

Official testing by the device for this program began in 2004 after legislation was passed in the General Assembly in 2002.


Two vans travel around Northern Virginia—Loudoun, Arlington, Fairfax, Prince William, and Stafford counties along with the cities of Alexandria, Fairfax, Falls Church, Manassas, and Manassas park—daily and set up in one-lane high traffic areas such as on-ramps. 

Teams set up the device and based on their recordings, they issue clean screen and gross pollutant notices, Olin said.

Enforcement officials retrieve contact information from the Virginia Department of Motor Vehicles by using the license plate numbers, said Roger Stiltner, an enforcement officer in Northern Virginia.

If car owners receive a clean screen notice, they can reregister their car without having to get it tested by an emissions inspector. Since 1990, Northern Virginia residents have had to get their cars’ emissions tested before reregistering every two years, Stiltner said.


If a car is deemed “dirty,” then a person would receive a notice in the mail stating that they need to have their car retested at an emissions inspection station and repaired to fix the pollution problem if the inspection still finds it a gross polluter, Olin said. Notices went out August 1, 2006, in Northern Virginia after two years of gathering data.


The resolution passed in the General Assembly in 2002 gave authority to DEQ to issue such notices.

Antique car collectors were concerned about the new policy, worried that they would be singled out because their cars wouldn’t pass EPA emissions standards, May said. But, the bill passed in 2004 exempts cars more than 25 years old from having to have their cars retested and repaired.

Electric cars, motorcycles, special fuel vehicles and cars two years and younger are also exempt from testing, according to DEQ officials.


On many occasions, the Remote Sensing device picks up on excess pollutants that derive from a more serious problem in a vehicle, Olin said. 

Getting a vehicle repaired, with or without a serious defect, also helps a car burn fuel more efficiently, according to Stiltner.  A repair can reduce a vehicle’s emissions by 95 percent, according to the ESP “I have a hybrid Prius,” said Olin.     “One of the benefits of the program is that I might not have to have my car inspected.”

“It gives people the incentive to keep their car clean and it helps us in our goal in meeting the EPA standards,” Stiltner said.


The EPA Clean Air Act requires states to explore “enhanced” emissions inspection and maintenance methods in “serious nonattainment areas,” such as Northern Virginia, according to Olin.  States with these areas also have to issue State Implementation Plans that outline how the state will solve air quality problems, said DEQ policy official Melissa Porterfield. The two-year emissions testing requirement is another one of many methods being used and has reduced emissions by 90 percent in Northern Virginia since 1990, Olin said.

There have been very few negative reactions to the testing, DEQ officials say.


“The people are more concerned with working with the program,” Stiltner said.  The enforcement station in Northern Virginia has received only one angry call since testing began, he said, but the caller’s complaint and name are still mysteries to officials.


The cost of vehicle repairs was also an issue debated by delegates when the bill was being considered, butit specifies a Vehicle Emissions Inspection Program Fund that could be used by people who can’t afford to pay for the DEQ-ordered repairs. The amount that will be available to a vehicle owner will be around $350, Olin said.  On the other hand, if vehicle owners do not repair their vehicles a $600 fine will be waiting for them.


Privacy advocates were concerned with the Remote Sensing device because a camera is triggered to take pictures of license plates to keep track of vehicles.  May said the technology was altered so that it only takes picture of the license plate, not the whole car.

After amendments were made to improve the bill and the technology, it was passed in the Virginia House of Delegates by a 94-3 vote and in the Senate by a 32-7 vote.


“It’s cheap, it’s fast and when used properly it saves a lot of time and money for a vehicle’s owner,” May said. The device can read one vehicle per second and 3,000 vehicles per hour if used continuously.  And after being tested in Virginia for the past 10 years and getting use in other states, Bill Hayden with DEQ public relations said, it has been proven to be accurate.


The accuracy of the device is an aspect that needs to be taken advantage of even more, says Porterfield.  She is working with Delegate John Cosgrove to present an interim report to the General Assembly in hopes of increasing the number of vehicles issued both clean screen and gross polluter notices.


This will prevent people from having to spend the time and money on getting their cars inspected if they are already exceptionally clean. It will isolate more of the problem vehicles that can be dealt with sooner. 


May said that one of the glaring facts that lead him to support a bill for using the ESP device was that 10 percent of vehicles contribute 50 percent of emissions. Issuing more clean screen and gross polluter notices will make the process even more efficient in Northern Virginia.

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A test site in Northern Virginia at an on-ramp to a highway.

An explanation of how the process works.


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