A fire in a private dwelling in Detroit gives us some real on-scene indications of how fire behavior and dynamics are explained in the fire research science being discussed and affecting tactics in the fire service today. This fire shows the flow path and the movement of smoke, heat, and fire. None of this is new; we have been venting, isolating, entering, and searching for almost as long as the fire service has been in existence. The awareness of flow paths, ventilation-limited fires (too rich to burn), and consequences of uncontrolled venting must be part of the training requirements for all firefighters and fire officers. With the modern interior contents, these too-rich-to-burn environments react quickly to any opening, allowing oxygen in the structure. Members need to understand the reactions to the actions they take on the fireground. Consider any opening made in the structure venting.
At any fire, the first consideration is the life hazard in the building. Is the building occupied or vacant? Is there a known or suspected life hazard? Are there searchable/survivable rooms? We know that all firefighters and officers operating at this fire are a known life hazard. If the building is vacant, we still have to perform primary and secondary searches throughout the space within the realm of safety for our members. There have been many cases of victims found in vacant buildings. We have to complete the searches and locate and extinguish the fire. Where did the fire start and where is it going?
At this fire, the conditions rapidly deteriorate once members force the front door and the ventilation-limited environment gets a new burst of oxygen. The introduction of oxygen into the fire compartment allows the fire to burn uncontrolled because of lack of compartmentation. Without the application of water, there are typically 90 to 120 seconds before interior conditions rapidly deteriorate and fire follows the path to the opening (the front door here). If water is not going to be applied to the base of the fire quickly, then we should control the front door and allow as little oxygen as possible into the fire compartment. The windows on the exposure D side start to fail, and additional oxygen is allowed into the structure. We do not know from the photos if members took these windows to vent the structure or if the windows failed from exposure to flame and heat. If you are operating at a fire and a window fails, that is critical information to communicate to the incident commander (IC) and interior forces, as the introduction of oxygen will change interior conditions. We have to accept that venting these types of situations prior to the application of water does not equal cooling. In fact, without water, you are going to increase the fire and temperatures. This is especially important if there is a wind condition and the wind is affecting that window. If you are planning or are ordered to take a window and you have a wind condition impacting that window or side of the building, that is also important information to communicate. That information might change the venting profile of the fire.
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