Twenty buses with the Pearl River County School District will now emit cleaner exhaust fumes thanks to the Mississippi Department of Environmental Quality and grant funds provided by other agencies.

A grant through MDEQ, using funds from the U.S Environmental Protection Agency and American Recovery and Reinvestment Act, will ensure that none of the expense of this upgrade work will fall on the school district, according to a MDEQ press release. The devices were installed at the school’s bus barn on Saturday by Waters Truck and Tractor Company.

MDEQ Communications Director Robbie Wilbur said the installation of the devices, called “diesel oxidation catalysts,” is comparable to installing a catalytic converter on a vehicle fueled by unleaded gasoline. The DOCs are being installed on the district’s 20 older buses. The program applies to buses produced between 1998 and 2006. The release states that buses made during and after 2007 were built with stricter emission standards so they do not need to be retrofitted.

According to the release, the DOCs will reduce particulate matter and carbon monoxide by 40 percent and also reduce hydrocarbon emissions by 70 percent. Reduction of those emissions will protect the health of the students that ride the buses while also reducing air pollution.

Wilbur said Pearl River County School District so far is the only district in Pearl River County to have the DOCs installed because that district was the only one to apply for them. The application process is still open and funds are still available, so that if those remaining districts decide to apply they can. Wilbur said MDEQ plans to finish the application process by December and have all of the DOCs installed in all qualified buses by May of 2010.

The price to install each DOC is about $1,150 per bus, for a total cost to install the devices on all 20 buses at the school district of about $23,000, Wilbur said.

Waters Truck and Tractor truck technician Joe Abercrombie said Saturday that the process was going smoothly, with each installation averaging about 30 minutes. He said the DOCs will not adversely affect the bus’ fuel economy. Seven mechanics were on hand to perform the installations on two buses at a time.

“We’re doing what we got to do to try to help the environment,” Abercrombie said.

The release states that DOCs consist of a porous ceramic honey-comb structure that uses a special coating to cause a chemical reaction within the emissions, effectively reducing pollution. DOCs require no maintenance and will be installed statewide at eligible schools that have applied for them with MDEQ.