By Mark van der Feyst
A major component of truck company operations is the task of ventilation: the systematic removal of heat, smoke, and unburned gases, and the replacement of them with clean air. By doing this, firefighters increase visibility inside the structure, reduce the amount of heat we need to deal with, and increase the chance of survival for any victims inside. Ventilation also allows the fire to be suppressed quicker and, to a certain degree, diminishes the intensity of the fire itself.
Ventilation can be accomplished in a number of ways: natural ventilation, hydraulic ventilation, negative pressure ventilation, positive pressure ventilation, and horizontal and vertical ventilation. Depending upon the situation presented, a team of firefighters can use one or a combination of techniques to ventilate a structure. Each method has its benefits and its drawbacks but can be effective depending on its application.
One quick method to ventilate a structure quickly is to remove the windows. This type of ventilation falls into the category of horizontal ventilation, and can be accomplished by one firefighter on the outside of the structure. Armed with certain tools, this firefighter can be very effective in the removal of hot gases, smoke, and heat. Seeing as the firefighter is on the outside of the structure, the need to have a team of two is not required. Accountability can be maintained by the firefighter with the incident commander (IC) or the incident safety officer.
Before any windows can be removed or broken, a few important factors must be considered. First, a quick size-up must be performed. The size-up will include life safety, fire and smoke conditions, the fire building and adjoining buildings, and the other operations that may be taking place.
Questions to ask when considering life safety:
- Where the occupants are located inside the building. Are they located between the fire and the opening?
- Identifying escape routes for rescues.
- The effects of ventilation on victims inside. Will it increase or decrease their chance of survival?
- Are we are venting for life?
Fire and smoke conditions questions:
- Are there backdraft or flashover conditions present?
- Will the opening lend to the development of the fire?
- Are we venting for fire?
When considering the fire building and adjoining buildings, we must consider:
- How close are the exposures?
- Will we create auto exposure?
- What size are the windows? They need to be a good size to allow for proper removal of smoke and hot gases and replacement of clean air.
When considering other operations that may be taking place, ask:
- Are search operations being conducted
- Is the hoseline in place, ready for fire suppression?
- Will the vent opening draw the heat and smoke towards attacking crews or away from them?
- Is this a coordinated effort?
Secondly, knowing where the fire is located will help in selecting the right window(s) to be removed. Arbitrarily breaking windows for the sake of ventilation will not work–it can and will lead to disastrous consequences. This information can be communicated from the interior search crews, the interior fire attack crews or the IC to the outside ventilation crew.
The firefighter assigned to take out the windows will need to equip themselves with the proper tools. The window’s location will dictate the type of tools needed. If we have a second-floor window to be ventilated, then a ground ladder or a long pike pole will be required. For second-floor applications, it is safer to use a ground ladder in conjunction with a smaller hand tool than to use a long pike pole. With a long pike pole, there is a greater chance of falling glass, which could lead to firefighter injury. Using a ground ladder will add more time as opposed to using a long pike pole. Good tools to use for window ventilation are the pike pole (six to eight feet), a roof hook (five or six foot), an ax, or halligan. The longer the tool, the better reach you will have when it comes to breaking the glass. A pike pole and roof hook will allow you to reach your target without getting too close. Too long of a pike pole will not allow you to have full control of the tool, whereas a shorter pike pole or roof hook will give you full control over the operation.
In photo 1, you can see a firefighter assigned to take out the ground floor window. He is equipped with a five-foot roof hook and safety glasses. As this was a training exercise, a self-contained breathing apparatus (SCBA) was not worn. If this had been a real working fire, it would be wise to wear an SCBA for personal protection. The firefighter in the photo is positioned to break the window with a forward chopping motion. His body is facing the window as he uses his arms to complete the movement. He is still off to one side of the window, allowing him to be protected from any expulsion of hot gases, smoke, or even fire. You will also notice that he has started up high on the window and is working his way down to the bottom. This will allow the falling glass to not become a cutting hazard for the firefighter.
In photo 2, instructor Tim Llewellyn is demonstrating another way to position yourself to break the window without fatiguing quickly. Notice how his back is to the building, still allowing him to be protected from any expulsion of smoke, hot gas, or fire. Instead of using a forward chopping motion to break the window, Tim will use a rotational motion to swing the roof hook keeping his arms static. Swinging the roof hook with his entire body allows Tim to exert more force to break the window without tiring himself out too quickly. Depending upon the type of window found within the structure, a good amount force may be necessary to complete the task. This position forces you to stay to the side of the window as opposed to the previous position, which allows a person to slowly creep in front of the window.
In photo 3, we have all the glass broken and removed from the window. Many of us might stop at this point and move on, however the task is not completed until the entire window is cleared out and open. You will notice the sash in the middle of the window along with some other jagged pieces of glass. Keep in mind that this opening can be used for firefighter survival. If a firefighter needs to exit the building quickly and wants to use this window, he will get caught by the sash and other debris. The window needs to be removed, sash and all (including the screen) to be an effective ventilated opening as well as a secondary exit for firefighters. A screen on a window will prohibit good exiting of smoke and hot gases by about 50 percent.
In photo 4, we have the finished product: a window completely removed and cleaned out. The firefighter is raking his roof hook along the sides of the window frame to ensure no sharp jagged pieces of glass are still present. If we are going to remove a victim through this opening, there remains a laceration danger, and we do not want to inflict more harm.
The task of removing a window for ventilation may seem simple and easy, but needs to be done with the considerations mentioned above. Any chance you get to break a window for practice is going to be the only time you will have for training on this. Use the opportunity to practice these different positions to find which one works best for you.
Mark van der Feyst has been in the fire service since 1999 and is a full-time firefighter in Ontario, Canada. He is an international instructor teaching in Canada, the United States, and India, and at FDIC. He is a local level suppression instructor for the Pennsylvania State Fire Academy and an instructor for the Justice Institute of British Columbia. He is also the lead author of Residential Fire Rescue (Pennwell).
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