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List of State Officials - Robert (Bob) L. Ehrlich Jr, Governor; Michael S. Steele, Lt. Governor; Kendl P. Philbrick, MDE Secretary 

Volume II, Number 6

 October 2006

eMDE is a monthly publication of the Maryland Department of the Environment. It covers articles on current environmental issues and events in the state. 

More Diesel Retrofit Projects in Maryland

By Bob Maddox, Air & Radiation Management Administration

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Closed-crank case ventilation system 

Diesel Oxidation Catalyst  

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Maryland continues to tackle the air quality problems associated with diesel fuel emissions. During the summer, school bus fleets in Anne Arundel, Prince George’s, and Montgomery Counties were retrofitted with equipment to reduce diesel exhaust emissions. These retrofitted buses now operate more cleanly and pose less risk to the health of students and drivers.

Now, the Maryland Department of the Environment (MDE) is focusing efforts to reduce emissions from other heavy-duty diesel vehicles. These vehicles play important roles in protecting citizens, yet pose health risks because of potentially harmful emissions.

Exhaustive But Worth It

MDE is diligently working with several jurisdictions to improve air quality by retrofitting emergency response vehicles, fire trucks, ambulances, trash trucks and dump trucks. These vehicles operate on diesel fuel and run their engines for extended periods. Exhaust from diesel-fueled vehicles contain several pollutants, including particulate matter (PM), carbon monoxide (CO), and nitrogen oxides (NOx). The PM in diesel exhaust can enter the lungs and aggravate asthma, cause lung damage and other serious health problems. Ironically, vehicles such as ambulances are responding to already vulnerable people and emitting harmful pollutants. The pollutants also have environmental impacts that contribute to regional haze and ozone formation.

In December 2004, after being awarded a Sensitive Population Grant from the U.S. Environmental Protection Agency, MDE began a partnership with the City of Baltimore, to start a project to reduce emissions from fire trucks and ambulances. “We met with the city and Donaldson [a retrofit equipment manufacturer] in June ’05 and inspected the trucks and ambulances,” says Lonnie Richmond of MDE’s Mobile Source Control Program. “The inspections helped us determine what equipment should be installed on those vehicles.”

“To date, 44 out of the 49 city-owned vehicles, slated to be retrofitted with pollution reduction equipment are completed,” said Richmond. A diesel oxidation catalyst (DOC) is a device that uses a chemical process to break down pollutants in the exhaust stream into less harmful compounds. The catalysts will reduce significant amounts of PM, carbon monoxide and hydrocarbons. The device cost between $1,000, to $1,500 to install, and requires no maintenance.

Leading By Example

To maximize the funding from the Sensitive Population Grant, MDE acquired several other willing partners. The City of Annapolis will be installing equipment on 10 emergency vehicles in October 2006. “We also took a look at our own emergency response and spill containment vehicles,” Richmond explains, “and we will be retrofitting six trucks by November 2006.” Next year, Montgomery County will equip 38 school buses with DOCs.

Because Trash Is Offensive Enough

Another project (Air Toxics Grant) to retrofit 106 of the City of Baltimore’s load packers (trash haulers) and 23 dump trucks with DOCs and closed crankcase ventilation filtration (CCVF) systems began in February 2006. To date, a total of 70 vehicles are retrofitted, and this project is expected to be complete by December 2006. CCVF systems allow the crankcase to be closed, which eliminates crankcase emissions without adversely affecting engine performance.

Retrofit equipment technology, combined with new diesel engine and diesel fuel standards are just some ways in which air pollution can be reduced and lead to cleaner, more breathable air.


©2006 Copyright MDE

Editorial Board
Maryland Department of the Environment
1800 Washington Boulevard, Baltimore, MD 21230