On Tuesday, September 27, a fire occurred in the roof-top battery compartment of a TransIT Services of Frederick County (TSFC) electric transit bus. An alarm sounded alerting the driver who pulled off to the side of the road and notified TransIT dispatch, who in turn called 911. A fire suppression unit in the battery compartment was activated and succeeded in limiting the damage to one battery. Fire crews had been previously trained in the proper method for extinguishing an electric bus fire and arrived on the scene quickly and extinguished the blaze. Damage was limited to the roof-top battery compartment and a small area on the roof and interior ceiling that is immediately under the battery compartment. The bus was transported to the refurbisher, Complete Coach Works (CCW), where a team, including Halsey King & Associates, conducted a fire investigation. The bus is under warranty and will be repaired at no cost to TSFC and returned in 30 days.
The remaining four electric buses were removed from service as a safety precaution to allow adequate time for a complete evaluation by CCW who had immediately dispatched two technicians to the TSFC property. The buses were returned to service once this evaluation was completed.
The Fire Investigation Preliminary Report cites two issues that led to the fire:
- A communication reporting module that monitors the batteries on this bus failed several days before, therefore did not alert regarding an increase in battery temperature
- A cable, which is usually crimped by a machine was inadequately crimped by hand, resulting in overheating and eventual fire
As a result of this report, all of TSFC’s electric vehicles have been inspected for proper electrical connections and proper crimping and have been deemed safe. The reporting module has been updated to provide an alert if there is a communication failure.
A final report is expected within the next 10 days. Results will be made available at that time.
