Montgomery County is pulling all of its fire-prone Champion Ride On buses off the road after another one caught fire Wednesday.
The latest fire, on an out-of-service bus next to the Silver Spring Metro station, was the seventh on a Ride On bus since 2009 and the sixth on a Champion-model bus, which resembles an airport shuttle.
The county pulled all Champion buses from service. Officials estimated 20 to 30 buses were pulled. An additional 25 were already parked, according to spokesman Patrick Lacefield.
The county was planning to pull the buses but was waiting until mid-August when it will have 30 refurbished Metrobuses, said Department of General Services Director David Dise.
The Ride On fleet will be short buses, Dise said. As a result, buses on Thursday and Friday will run on a holiday schedule.
The union that represents bus drivers has been asking the county to pull the buses since February.
"Dise has been playing Russian roulette with the lives of our drivers and the lives of the public," said Gino Renne, president of the Municipal and County Government Employees Organization.
Though Dise said Montgomery County inspected all Champion buses after each fire, they put them back on the roads after repairing any problems. By comparison, Metro pulled its 94 Orion VI buses after two caught fire in April.
The cause of the Champion fires is still not clear, nearly two years after the first one caught fire.
The National Highway Traffic Safety Administration opened an investigation in March after finding that three fires originated in the buses' transmissions. That inspection showed that the parking brake can be unintentionally applied while the buses are moving, causing fires, the federal agency reported. The investigation is continuing.
County Executive Ike Leggett, who told Ride On to pull the buses, said the county can't be sure about the cause. He emphasized that "human error" -- the bus driver reportedly did not pull over immediately when he saw a warning light turn on -- and Wednesday's excessive heat could have played a role in the fire.
The county has funding for 28 new buses this fiscal year and potentially 24 more in fiscal 2014, Dise said.