British Columbia Retrofit Program
Eyes Completed Installations

VICTORIA, B.C. - About 500 provincial school buses are scheduled to be retrofit this month with diesel oxidation catalysts and closed crankcase ventilation filters as part of a $800,000 Canadian funding effort by the country's environmental regulation agency and local districts.

The Canadian Environmental Protection Act of 1999 listed particulate matter fewer than 10 microns (PM10) emitted by diesel engines as a toxic substance and a suspected carcinogen. While newer buses purchased after 2006 will run on ultra low sulfur diesel, the B.C. School Bus Emissions Reduction Program aims to reduce emissions from older school buses that could remain in operation during the next couple of decades.

Richard Holt, project engineer with Environment Canada's Pacific and Yukon region, said the campaign originated out of a $60,000 Canadian retrofit pilot program for 50 buses conducted last year with Abbotsford School District No. 34, Fraser Valley Regional District and Chilliwack School District No. 33.

The program benefits 27 public school districts and one private school district, which constitute nearly half of the number of provincial school districts but a good portion of the eligibility pool. Frank Marasco, executive director of the Association of School Transportation Supervisors of British Columbia and manager of transportation for North Okanagan-Shuswap School District No.83, explained that many rural school districts do not operate school bus fleets. In the end Environment Canada donated about $560,000, and local in-kind contributions picked up the difference.

Holt added contractors are also eligible for the program.

Engine Control Systems, a division of Lubrizol Canada Ltd., will supply 302 DOCs and Cummins Western Canada, a distributor for Fleetguard, will supply 202 CCVs. The manufacturers were chosen from among five other companies during a "request for quotations" process initiated last September. Holt said most of the participating school districts elected to have the vendors install devices, but about six are performing the work in-house. Completion is expected by March 31.

Older pre-1994 model year buses were the perfect candidates for DOC retrofits. Holt said Environment Canada considered the average annual mileage for each bus and the expected remaining life of the bus and found that the older buses emit the higher levels of PM 10 . Typically the DOCs figure to reduce emissions on those vehicles by 20 to 50 percent, he added.

As for the crankcase ventilation filters, newer school buses in the age range of 2000 through 2005 were targeted because they showed a higher percentage of in-cabin pollution. Holt pointed out that the exact source of these emissions remains unclear, whether they originate from the school bus itself or other on-road factors such as open windows while driving, opening the loading/unloading door with front-facing engines or caravanning behind other school buses.

Some buses received both retrofits.

As for vendor selection price was but one factor, Marasco said, with U.S. EPA verifications for ultra low sulfur diesel and product innovations being just as important. Engine Control Systems was the only DOC manufacturer with a verification letter for the lower emission diesel, which will be required for all fleets later this year. Rather than using a traditional fuel filter, Fleetguard's CCV contains an impactor that is less expensive and entails less maintenance.

The byproduct of combustion is residual oil exhausted through crankcase ventilator, explained Brian Hazelwood, parts marketing manager at Cummins Western Canada. The Fleetguard impactor basically serves as a brick wall that blocks this exhaust. Gravity forces out the liquid, which drains back into the crankcase. Vapors are then drawn back into the clean side of the air intake system.

"It truly is a closed crankcase ventilation system," he added. "There is no ventilation."

Marasco said the province has an average fleet lifecycle of 12 years, "so no buses that will be heading out in the next two years are included." After purchasing 12 newer buses already equipped with the latest engine controls for School District No. 83, which has a fleet of 54, and this month's installation of DOCs and CCVs on another 36, only 6 buses will remain with outdated emissions systems.

"With everything that's going be done, in two years we will be 100 percent," he added. "We're already high mileage fleet."

Source: School Transportation News, March 2006. All rights reserved.