Vertical ventilation
Vertical ventilation Vertical ventilation: A firefighter’s ladder-to-roof guide. Back to basics – sounding and walking on the roof, using roof ladders, working from an aerial, cutting the hole and punching through Chris DelBello provides a detailed guide into vertical ventilation. DelBello is a 31-year veteran of the fire service. He currently holds the rank of senior captain with the Houston Fire Department, working in the Midtown District. He is also the district training officer, which encompasses all the stations in downtown and midtown. DelBello holds a Training Officer II certification and serves as an adjunct instructor with Houston Community College. Vertical ventilation is an essential and effective fireground tactic. For well over 100 years, vertical ventilation has been used by the fire service, proven as a viable ventilation method on thousands of incidents across America and beyond. In fact, it has long been considered the optimal method of ventilation. In some departments, it is still the best option due to budget constraints that would prohibit the purchase of positive-pressure ventilation (PPV) fans. And depending on what the fire conditions are, it may literally be the only option. Case Study A ladder company was traveling down a tight residential street, when they rolled up on a wood-frame residential structure with heavy smoke pumping from every crack in the building. The humidity was high that morning. The smoke was initially lifting and then falling to the ground level, making it difficult to see even while outside the building. Neighbors and other bystanders were yelling and pointing at the house, indicating that there were children inside. The ladder company officer radioed dispatch, advised them of the fire and requested a box alarm, all while trying to gear up as quickly as possible. Once the crew was geared up, they attempted a primary search. The crew entered a door on the bravo side. As the officer made entry into the zero-visibility conditions, he quickly began to run into items not typically found inside one’s residence – first a mattress on the floor right in the entryway, then a shopping cart, then a push-mower, then rolled-up cyclone fencing. As the company officer continued on, it felt like he was also walking upward, not like a run of stairs, but more like a mountain of garbage. Soon the officer’s helmet bumped the ceiling. The officer stopped and asked himself, “Do I continue on or do I abandon the search?” At this point, the company officer is no more than 10-12 feet inside the doorway, and they were still the only company on location. The officer decided to abandon the search, opting for vertical ventilation. As the company returned to the alpha side to retrieve the necessary equipment to perform vertical ventilation, the officer saw that the ladder company chauffeur had already set everything up to make access to the roof – and the vent saw was already running. The crew grabbed the saw from the chauffeur and climbed the ladder. The crew cut a nice-sized hole on the pitched roof, and heavy smoke began pumping out. As the crew left the roof, heavy fire began showing from the hole. The ladder company then re-entered the residence. As the company walked through the house – yes, walked – they could see clear as day, that is, until they made it to the kitchen. The entire stove, sink, cabinet and pantry area was free-burning, and all the products of combustion were exiting directly through the ventilation hole the crew had just cut. The company officer and crew finished the primary search and exited the residence to retrieve some pump cans to initiate extinguishment, while at the same time, the first engine company arrived on scene. The ladder company officer directed the engine company officer to the kitchen and the fire was quickly extinguished. Vertical Ventilation Vertical ventilation is the removal of super-heated toxic gases and smoke by allowing it to take its natural traveling path – UP! Fire companies make this possible by accessing the roof with a ladder, saws and other tools, and making an opening on the roof’s exterior, then punching the ceiling out with another tool. The final outcome of this tactic is that the super-heated smoke and toxic gases exit the building on their own. Vent crews simply provide the path of least resistance by cutting a hole in the roof decking large enough to release any products of combustion under pressure while confined within the structure. Company officer Most members will receive minimal training, including hands-on training, before going to the roof for their first time. Let’s train them to be safe. Let’s train them for that experience right here. Training at this level is the company officer’s responsibility. The company officer needs to start by explaining every aspect of when, how and why the crew will perform vertical ventilation. The company officer leads the way on this tactic, and they are responsible for training their crew to the level needed to complete the task safely. Every action must be explained and practiced over and over until there is complete understanding. It starts with the training, but once on scene, the company officer should assume the position of a formal roof safety officer. The officer decides how the roof will be accessed and where the ladder will go, the path the crew will travel when walking on the roof, and where the hole will be cut. The company officer then supervises the crew doing the actual cutting, making sure they do not walk on their cuts, that they do not step off the roof, and that they do not walk anywhere that has not been checked for weakness. Sounding the roof Sounding the roof should not be accomplished with a size 10 boot. If your boot goes through, you are already in trouble. Sounding the roof is also not accomplished by simply tapping an axe head inches in front of each step taken. Sounding should be accomplished with a 6-, 8- or 10-foot
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