During his FDIC 2012 classroom Thursday, Brian Brush discussed recent advances in scientific understanding of fire behavior and the impact of ventilation on firefighting.
Brush, a lieutenant in West Metro Fire Rescue in Lakewood, Colorado, and a contributor to Fire Engineering and Fire Apparatus & Emergency Equipment, began the class by reflecting on the numerous advances firefighters have experienced in recent years. Despite new and better technology, the fire environment continues to kill and injure firefighters and civilians; despite firefighters arriving on scene more rapidly that in the past, fires are reaching flashover even faster than firefighters can arrive to begin suppression.
Firefighters must not look to technology or increased staffing to save them, Brush said. Technology can only provide new tools, and increased staffing in these difficult economic times is unlikely. Only a better understanding of how ventilation affects fire behavior can increase firefighter safety.
Brush pointed to the death of Brian Carey at a Homewood (IL) house fire as an example of how ventilation errors can lead to firefighter line-of-duty deaths. Data suggests that ventilation mistakes are the leading tactical reason for fireground injuries and deaths.
“Only understanding ventilation can make us safer,” said Brush. “We need to get smarter about it and better at it.”
Brush examined Underwriters Laboratories (UL) that showed how fires behaved in enclosed structures. He emphasized that fires in enclosed structures are ventilation controlled, therefore even something as seemingly simple as forcing a door before advancing a hoseline into a structure can provide a flow path for an apparent dormant fire to take off and grow. “Forcing a door is ventilation,” Brush affirmed.
Brush discussed various means for trying to control fire behavior through ventilation, including using vertical ventilation to allow heat to follow it’s desired path (“Heat wants to go up,” he said); horizontal ventilation to allow high-pressure that has built up inside a compartment to move to a low-pressure area, ideally in a direction opposite that of attack lines; and of using mechanical methods such as fans to try and affect fire behavior–probably the least predictable method of the three.
The UL studies (CLICK HERE to see them) are providing scientific evidence for some ventilation tactics that the fire service has used for years, Brush said, and they form a part of the changing language firefighters must learn to deal with ventilation concepts.
“If we can control the ventilation,” Brush stressed, “we can control the fire.”
For training articles by Brian Brush, consider On Firefighter Training: Being Your Best Is Their Best Chance and Benefits of Conducting a Nozzle Study: Equipment and Operations.