lunedì 22 agosto 2011

School bus pollution

24 million American children ride school buses daily. On average, these students spend an hour and a half each day in a school bus. School buses drive more than 4 billion miles each year. School buses are the safest way for children to get to school. However, pollution from older diesel vehicles have health implications for everyone, especially children. Clean School Bus USA (EPA based) brings together partners from business, education, transportation, and public-health organizations to work toward the goals of reducing the potential health impact on children. School districts, with the help of federal grants (and state grants in some cases) have been working to replace the oldest, most polluting buses, and to upgrade others with better pollution control equipment. (The Diesel Reduction Act was reauthorized for five years in December 2010, but it's unclear how much money Congress will appropriate to continue the program.) The way drivers operate the buses can also have a big impact on the air quality for kids.

School buses are a necessary evil despite some issues such as diesel pollution fumes.
Unnecessary school bus idling pollutes the air, wastes fuel, and causes excess engine wear. Fortunately, it's easy to implement practices that reduce school bus idling. This also applies to all of those people who drive their kids to school and let their cars idle in lines.
Idling school buses can pollute air in and around the bus. Exhaust from buses can also enter school buildings through air intakes, doors, and open windows. Diesel bus exhaust from excessive idling can be a health concern.
Idling buses waste fuel and money. When idling, a typical school bus engine burns approximately half a gallon of fuel per hour. School districts that eliminate unnecessary idling can save significant dollars in fuel costs each year.
Any bus built before 1998 should be considered a prime candidate for replacement because older vehicles are designed with higher air emission standards in mind. The ideal current goal is to have a fleet of buses built since 2007, when a new law went into effect requiring closed crankcases and advanced emissions controls to limit the emissions of soot and other harmful pollutants. On older buses, having drivers close the crankcase reduces pollution inside buses significantly.
Despite the air quality problems that persist in older buses, the bus is still the most efficient and least-polluting way to get most kids to school as well as the safest. If everybody drove to school there would be fifty vehicles for every bus spewing fumes and blocking traffic flow.


[ enn.com ]

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