NFPA Journal ®, September/October 2006
This analysis was prepared for the National Transportation Safety Board’s (NTSB’s) Public Hearing on Motorcoach Fires on August 8 and 9, 2006 that was called in response to the September 2005 Texas motorcoach fire that claimed 23 lives. The analysis is based on data collected by the U.S. Fire Administration’s (USFA’s) National Fire Incident Reporting System (NFIRS) and NFPA’s annual fire department experience survey. Vehicle fires were identified by NFIRS incident types 130-139 and buses or school buses were identified by mobile property type code 12. This code also includes trackless trolley buses; statistics for this code cannot be broken down further to separate trackless trolleys or school buses from other buses. A proportional share of vehicle fires in which the mobile property type was unknown or not reported are also included in this analysis. For most causal factors, unknown data is allocated proportionally across the known.
Some 2,210 bus or school bus fires, on average, were reported annually from 1999 to 2003. During this five-year period,
Reported bus fires rose 4 percent from 2002 to 2003 but the overall trend in recent years has been flat.
Bus and school bus fires are less common on weekends
December had the smallest number of these fires. Overall, the difference between months was small. Bus and school bus fires were much less frequent on the weekend than the rest of the week, with just 8 percent on Sunday and 11 percent on Saturday.
73 percent of these fires are reported between 6 a.m. and 6 p.m.
Many bus and school bus fires occur on non-road properties.
This is important because such properties generally do not fall under the jurisdiction of the National Highway Traffic Safety Administration (NHTSA), the body that regulates highway vehicles. Forty-five percent of these incidents occurred on streets, roads or driveways; 15 percent were on highways or divided highways. Although driveways are grouped with residential streets and roads in the NFIRS codes, they are generally not considered part of the public road system. Twelve percent occurred in vehicle parking areas, another property outside of NHTSA’s domain.
Equipment or other heat source failures caused three-fifths of the bus and school bus fires.
Mechanical failures and malfunctions were leading contributing factors.
NHTSA estimates that in 2004, only one of 275 fatal bus crashes resulted in a fire, and that less than .05 percent of all reported bus crashes resulted in fire.
Design, manufacturing, or installation deficiencies were factors in only 1 percent of the reported bus or school bus fires. The heat source in one-fifth of the bus and school bus fires was radiated or conducted heat from operating equipment; arcing was the heat source in another 20 percent.
The 1999 model year was the most common in bus and school bus fires in 2003.
Electrical wire or cable insulation was the item first ignited in 29 percent of the bus and bus fires. Twenty-seven percent of the bus and school bus fires began with the flammable or combustible liquids or gases, piping, or filters.
Marty Ahrens is the manager of NFPA’s Fire Analysis Services.