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CORNICE FIRE Here we have a photo of a roof of a row of two-and-a-half- or three-story buildings, depending on how your building code measures height. While they are attached in this photo, we know that (while built at the same time) they have brick walls separating them. Oh, fire can extend in such construction, but it is usually rare and, when it does, it is often through sloppy work on brick mortar in the side walls and in the unseen wall in the cockloft. Now let's take a look at some of the other things in this photo. What about the aerial and portable ladder position? Pretty good, I think. The aerial tip is a good distance above the roof of this top-floor fire. It is also for the firefighters assigned the tactics of vertical ventilation and is expected to remain there, except for emergencies for a considerable length of time. The portable ladder is also to a roof-area work platform to the top floor rooms in the adjacent building to the fire structure. What is on fire that we see in this photo? It is the cornice of the fire building. It is an open, decorative construct that was common in turn-of-the-century buildings and through a quarter of the 20th century. They really served no purpose that I know of, except to act as a fuse for extending fire should the original fire extend into here. These cornices are virtually inaccessible from the interior and through the top-floor ceiling as is the rest of the cockloft fire. Opening the roof here does not vent the cornice area, at least not enough to affect the horizontal spread to the next building cornice. The vent hole necessarily has to be put into the rise in the roof boards at the edge of the front enclosure wall. A triangle is the best cut, with the base along the outside edge to stop the heat sink buildup and retard the horizontal spread and to indeed provide an access hole to attack this remote location with hose lines from the roof. The other alternative is to work very hard from the roof to loosen the entire assembly and to pull it onto the roof or drop it to the ground. This is another area where tower ladders and their versatility shine. This crew has little time to stop this spread, as is seen from the flame pressure showing at the joint of the two cornice constructs but it is the only way. As far as the top-floor fire is concerned, what else do you see? Well, given that this is our fire and we have crews operating on the inside to extinguish fire in the cockloft from below and still conduct a secondary search (primary done, it is hoped), what of the ventilation of this floor? If this were a fire in my district, I would have a serious talk with the team at our critique. There is no reason why those windows on the top floor front are still IN! A top-floor fire is one of the most serious life hazards because of the intense smoke condition that is found associated with it. Vertical ventilation is a must for sure, and this is the time to prepare and begin to cut a roof opening after opening all the constructs the builder gave you (skylight, scuttle, light, and air shafts). It is the responsibility of the outside Enter-Search-and-Vent (ESV) team to assist in horizontal ventilation. If your roof team is sharp, horizontal ventilation from the roof with tool and rope is an easy accomplishment after vertical ventilation and before roof cutting. Remember, don't expect these cornice areas to be accessible from inside the structure. Think to yourself on arrival: how did it get there in the first place? Another thought: how many of you actually believe that these wires are all telephone and video cables? Put this picture in your district and have fun with it at the kitchen table on shift. BACK TO PHOTO LESSONS TABLE OF CONTENTS © Copyright Firenuggets.com 2004 Click here for Terms and Conditions of Use |