Dan Burgard is leading a project to test tailpipe emissions of buses at the Federal Way Transit Center. His tool of choice? A beam of light.
King County Metro, Sound Transit and Pierce Transit have been installing emission-reduction systems on buses. Burgard, an analytical chemistry professor at University of Puget Sound in Tacoma, wants to see if they work.
On June 6, Burgard and crew installed the FEAT (Fuel Efficiency Automobile Test), a device that measures tailpipe emissions from vehicles in motion. The devices are mounted on scaffolding at the transit center’s exit at South 317th Street and 23rd Avenue South. A remote sensor analyzes vehicle emissions with infrared and ultraviolet light. This light detects carbon dioxide, carbon monoxide and other chemicals in the air that are present before and after a bus passes through the testing space.
“Every gas has a fingerprint of light that it absorbs,” Burgard said, referring to detection of these emission gases.
The experiment is an application of spectroscopy, which is the study of light absorption. Matt Breuer, a Federal Way resident and junior biochemistry major at University of Puget Sound, will lead the testing through about June 16 for an undergraduate research project.
Burgard chose the transit center because of the varying ages and types of buses that pass through daily, allowing for more comparisons. Some buses are diesel-hybrids, some buses run on compressed natural gas, and some buses are several years old.
Burgard expects to share final results with Sound Transit by the end of summer.
“The agencies in this area, at least in my mind, are very proactive in reducing emissions,” he said, noting Pierce Transit’s transition to compressed natural gas (CNG) as fuel for buses. In another example, Sound Transit’s 40-foot CNG bus is designed to cut nitrogen oxide and carbon monoxide emissions by 90 percent compared to diesel-powered buses, according the transit authority.
Burgard performed a similar experiment in 2010 at the weigh station off Interstate 5 in Federal Way. He led a project that measured emissions of semi-trucks and found a drastic decrease — a result of requirements by the Environmental Protection Agency that went into full effect in 2007.
