The Ohio Department of Education estimates that 1.3 million Ohio children ride school buses to and from school every day.
The Ohio EPA wants to ensure that buses are not only the safest but also the cleanest way to transport children by offering the Clean Diesel School Bus Fund Retrofit Program to target buses of model years 1994-2006, that have more than 5,000 miles on them. The goals of the program are to retrofit existing school buses with devices and/or cleaner fuels that reduce pollution, to reduce school bus idling and to improve air quality.
According to the Ohio EPA Web site, 21 buses in Washington County were retrofitted between March 2006 and July 2010.
Among those school districts who received a grant to retrofit some of their buses was Wolf Creek Local Schools.
Tim Rankin is a mechanic and transportation coordinator for the district and said that two buses along the eight routes have been retrofitted to control emissions in the past few years.
"They're retrofitted for emissions reduction in the exhaust of the older buses; older buses get new catalytic mufflers and a couple things to reduce pollutants," he said.
One of the retrofitted buses has been retired and a new bus was recently acquired by the district.
"We retire them based on mileage or age or a combination. The new buses have all the latest emissions standards and a new design," Rankin said.
Two model 2012 International and three Thomas buses have recently joined the fleet at Frontier Local Schools, according to transportation coordinator Gary Bookman. Not only do the buses offer such safety features as differently-shaped windshields and side windows for greater visibility, and a shape designed to be more aerodynamic, the buses- and all new buses currently rolling off the lines - also have a special tank to use special fuel.
"It's called diesel exhaust fluid and, basically, it's made out of fertilizer," Bookman said.
Aqueous Urea Solution (AUS32) is used in a process called selective catalytic reduction (SCR) to reduce emissions of oxides of nitrogen from the exhaust of diesel engines.
AUS32 is a 32.5 percent solution of high-purity urea in demineralized water that is clear, non-toxic and safe to handle.
According to the EPA, the latest diesel engine emission standards require that engine manufacturers reduce the amount of nitrogen oxides (NOx) emitted. To reach these NOx emissions levels, engine manufacturers employ SCR as an after treatment technology that when combined with exhaust gas recirculation (EGR), is supposed to reduce
NOx emissions to the level prescribed by EPA standards.