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E-M:/ Diesel study results released

Title: Diesel study results released
Preliminary Results of School Bus Diesel Study
Show that Tailpipe Emissions Can Be Eliminated
Diesel Particle Filter with Cleaner Fuel Makes Children's Ride Healthier

Elizabeth Harris, East Michigan Environmental   Action Council  Tel.: 586/306-8664 Action Council
Mary Beth Doyle, Ecology Center                         Tel.:  734/663-2400  x 108
Randy Trent, Ann Arbor Public Schools                 Tel.:  734/994-8118
Rusty Russell, Clean Air Task Force                     Tel.:  617/515-9522 

        ANN ARBOR (April 30, 2004) - Initial results of a test of diesel engine pollution from Ann Arbor public school buses demonstrate that an easy-to-install, widely available technology can virtually eliminate emissions of very small particles from bus tailpipes.  Diesel soot particles present a health risk while children are riding buses to school, and while they are waiting to board idling buses outside of school buildings.
       The testing was conducted in mid-April by the Ann Arbor Public School District, two Michigan-based environmental and public health groups - the Ecology Center and the East Michigan Environmental Action Council - and by the Clean Air Task Force, a national organization that works with local partners to clean up buses and power plants.  Preliminary results were released today. 
      "Riding the school bus is still the safest way for our children to get to school, but the ride could be an even more healthy experience if we cleaned up emissions from the tailpipes of our buses," said Randall J. Trent, Director of Environmental and Utility Services for the Ann Arbor Public School District.  "We are committed to taking further action to add emission controls to our buses, and have put in a request for funding from an upcoming bond issue," Trent added.
        Diesel soot contains a high percentage of fine and ultra-fine particles - technically called PM
2.5 and PM1.0 - which can be less than 1/100th the width of a human hair.  Soot has been found to trigger asthma attacks in children, and has other health impacts.
      Emissions from a test bus - selected for its average age and usage, and driven on a typical route - were measured both before and after it was outfitted with a diesel particulate filter and ultra-low sulfur fuel.  With the filter and the fuel, soot emissions from the tailpipe dropped from levels that exceeded the range of the testing equipment down to virtually zero.
       "These test results should encourage other school districts to follow Ann Arbor's lead and make operating cleaner buses a priority," said the Ecology Center's Mary Beth Doyle. "Particle filters are widely available and Michigan is one of the few areas in the country in which ultra-low sulfur diesel fuel can now be purchased.  This is especially important given that new federal regulations mandating cleaner buses apply only to new equipment purchased after 2007 - not to the familiar yellow school buses that are on the road now," she added.  "And some of those buses will still be in operation in the year 2015."
        Diesel soot generally enters a bus through its doors.  That happens while the bus is driven on its route, as well as while it idles outside of a school, waiting to pick up students.  Several communities in Michigan have adopted anti-idling ordinances that are helping to keep students safe as they wait to board the bus.
        "A bus can start its route filled with diesel soot if it is allowed to idle for ten or twenty minutes," stated Elizabeth Harris, Executive Director of the East Michigan Environmental Action Council, which also was involved in the bus study.  "West Bloomfield has an anti-idling program because parents were concerned for their children and decided to take action."
    A few other communities, such as Bloomfield Hills and Birmingham, have anti-idling policies and others have said they will adopt policies soon.  "We urge parents to tell their school districts they want anti-idling policies," Harris added.
A school bus emits diesel soot particles in two ways.  Most emissions come from the tailpipe, but some come from the engine crankcase.  These emissions affect students in two places - while waiting for the bus, and while riding it.
        Another segment of the study focused on emission levels next to idling buses.  Alongside a conventional diesel bus, soot levels flew off the charts.  But emissions from the same bus, when equipped with a diesel particle filter, were nearly indistinguishable from low background levels.  The research team also tested a second piece of equipment that was designed to eliminate emissions from the engine itself.  This device did not perform as well as hoped, and members of the team expressed interest in testing other available options later this year.  Researchers were assisted by a group from Purdue University under the direction of Dr. Neil Zimmerman, and graduate students from the University of Michigan under the direction of Drs. Stuart Batterman and Tom Robins.
      "We think that, by demonstrating in a rigorous way that communities can make significant strides in eliminating their children's exposure to diesel soot emissions, more cities and towns will follow Ann Arbor's lead and decide they want to learn more about the effects of diesel soot and the cost-effective manner in which they can address the problem," stated Dr. Bruce Hill, Senior Scientist with the Clean Air Task Force. 
        Founded in 1996, the Clean Air Task Force (www.catf.us) is a nonprofit organization dedicated to restoring clean air and healthy environments through scientific research, public education, and legal advocacy.  CATF's staff includes scientists, engineers, economists, MBAs and lawyers.  The organization works closely with more than 40 state, local, regional and national groups to educate the public, media, industry and public decision makers on the science and economics of clean air policies through fact-based and locally appropriate advocacy.
     East Michigan Environmental Action Council (www.emeac.org) is nonprofit, public interest group whose mission is to "protect and restore land, air, water and diversity of life through informed personal and public action."  The organization was founded in 1970 and is based in Bloomfield Hills, Michigan.  EMEAC's accomplishments include legislative and legal changes that have increased protection for land, air and water, and the preservation of biological diversity.  It also is engaged in educational activities that help to raise the level of public understanding about environmental issues.
      The Ecology Center (www.ecocenter.org) is a Michigan-based nonprofit organization that works for clean air, safe water, and environmental health.  The Ecology Center's programs work to transform the environmental practices of the automobile, health care, and chemical industries, to implement smart growth policies, and to promote waste reduction and recycling. 
        The Ann Arbor Public School District covers 125 square miles, serving the city of Ann Arbor and parts of eight surrounding townships.  The district has 20 elementary schools, one K-8 open school, five middle schools, two comprehensive high schools, three alternative high schools, one pre-school and one adult education program.  It serves the needs of more than 16,800 students in grades pre-kindergarten through 12.  The district employs more than 3,000 full- and part-time staff members.  Approximately 76% of the teaching staff holds a master's degree or above.  The district operates a school bus fleet of 125, 110 of which are on the road at any given time. Its website is: www.aaps.k12.mi.us


Mary Beth Doyle, MPH
Environmental Health Project
Ecology Center
117 N. Division
Ann Arbor MI 48104

734-663-2400 ext 108
734-663-2414 (fax)