Management & Operations

CARB study measures CNG, diesel bus emissions

Posted on May 1, 2002

Study results released in April by the California Air Resources Board (CARB) assert that buses running on both compressed natural gas (CNG) and ultra-low-sulfur diesel fuel, with the proper emission controls in place, can attain significant reductions in toxic emissions. The testing, which was conducted from March 2001 to June 2001, compared exhaust levels of a diesel transit bus equipped with emission control technology to another diesel bus and a CNG bus that had no particulate filter or after-treatment equipment. Test results confirmed that CNG buses emit lower levels of particulate matter and nitrogen oxide than diesel fumes. However, information gathered in the study also demonstrated that the level of some toxic pollutants given off by CNG buses can be substantially higher than those found in “clean diesel” fumes. The study produced favorable results for diesel buses using a particulate filter. The diesel bus running on ultra-low-sulfur fuel had lower emissions than the unequipped diesel and CNG buses in the amount of toxic organic compounds and total mass of particulate matter. “When the diesel bus was retrofitted with a trap and run on low-sulfur fuel, its performance was very promising,” said Dr. Alan Lloyd, chairman of CARB. “We are working now to obtain better performance from CNG buses when they are equipped with state-of-the-art after-treatment equipment.” Currently, tests are being conducted using CNG buses with new manufacturer-installed oxidation catalysts. Results of those tests will be released in mid-2002. A joint statement from several organizations in response to CARB’s results claimed that the study’s comparison of buses was unfair because the CNG bus tested was not equipped with the most up-to-date clean-air technology. The statement did offer an endorsement by the groups of the perceivable improvements in diesel fuel emissions as well as CARB’s efforts to improve bus emissions. The organizations that drafted the statement include the American Lung Association, Coalition for Clean Air, Natural Resources Defense Council, Planning and Conservation League, Sierra Club and Union of Concerned Scientists.

View comments or post a comment on this story. (0 Comments)

More News

JTA's Ford wins prestigious COMTO award

The Thomas G. Neusom Founders Award is the highest honor bestowed by COMTO. Ford accepted the award at the 46th National Meeting and Training Conference in Detroit.

NJ Transit weighing disciplinary actions for no-show train engineers

It's unclear how many of the cancellations stemmed from engineers exercising a contract provision that allows them to take two days to report for work when schedule changes are made.

National Express Transit acquires Cook DuPage Transportation

Established in 1975 and based in Chicago, CDT operates 275 paratransit vehicles providing more than 80,000 trips per month to PACE users in the Chicago Metropolitan area.

MTA chief weighs food ban on subway after track fire snarls service

A garbage fire crippled subway service along four lines for more than two hours during the peak of Monday’s morning rush hour.

BYD commits to hiring from communities facing significant barriers to employment

In addition to targeting veterans and returning citizens, will also target populations that have historically been excluded from the manufacturing industry, such as women and African-Americans.

See More News

Post a Comment

Post Comment

Comments (0)

More From The World's Largest Fleet Publisher

Automotive Fleet

The Car and truck fleet and leasing management magazine

Business Fleet

managing 10-50 company vehicles

Fleet Financials

Executive vehicle management

Government Fleet

managing public sector vehicles & equipment

TruckingInfo.com

THE COMMERCIAL TRUCK INDUSTRY’S MOST IN-DEPTH INFORMATION SOURCE

Work Truck Magazine

The number 1 resource for vocational truck fleets

Schoolbus Fleet

Serving school transportation professionals in the U.S. and Canada

LCT Magazine

Global Resource For Limousine and Bus Transportation

Please sign in or register to .    Close