Article and photos by Tom Kiurski
On this training day, we used an old shed that was to be demolished. Although not the typical structure we would use for training, the opportunity arose and we planned a drill.
The training subject, enlarging existing openings, covers such techniques as making a door out of a window to allow removal of a downed firefighter or civilian, when that victim can’t be removed through a more typical opening because it is cut off by fire. Although ideally suited for wood-frame dwellings, this evolution can be modified for use in other structures in your response district.
After our firefighters discussed the above situations that would require such a tactic, we covered some safety issues. First, shut off the building’s power. Avoid enlarging the opening in the room in which the rapid intervention team (RIT) is operating. Make the opening as close as possible to where the RIT is operating, but not in the same room, because of the hazard a chain saw presents in the RIT’s working space. The team making the enlargement should work closely with the RIT leader and the incident commander (IC) so that all parties are aware that this activity is going on. An enlargement team member should enter the structure at the opening (be sure to check the floor before entering) to ensure the safety of the cutting operation.
Break any glass in the opening and clear it of all items that may bind the saw’s chain. Most wall thicknesses are between five and 10 inches, so the chain depth can be preset if your saw has that option.
The outside enlargement team needs a chain saw, a ladder (for the member entering the opening to act as an inside safety watch), and several hand tools. To avoid spending too much time on the cut and putting unnecessary wear on the saw, make the cut just inside the frame of the opening you’re working on. Avoid unnecessarily cutting any other structural and window framing supports.
(1) Preparing to enlarge this window opening includes removing as much of the glass, curtains and furniture from where the cuts will be made inside the window. Click to enlarge
(2) The first cut is vertical, just inside the window frame, and extends down near the floor, if possible. Ideally, have an interior firefighter observe the cuts. Click to enlarge
The two-cut and the three-cut methods are the two main options for enlarging a window opening. For the two-cut method, make two cuts downward with the chain saw from a position just inside each window frame until you reach about floor level. Stop cutting if you feel the chain binding on any building features such as pipes and conduits. The bottom of the new opening will then be level with any such obstruction. The outside team then uses pulling tools to pull that wall section down and move it out of the way.
(3) In this photo, the second cut is horizontal along the floor. The third cut is vertical near the other window frame, extending downward to complete the opening enlargement. Click to enlarge
The second method involves making three cuts. The first cut is one of the vertical cuts, and the second cut is a horizontal cut from the bottom of the vertical cut, presumably near the floor level. The third cut is the opposite vertical down to meet the horizontal cut. The remaining piece of wall can be removed from the opening and moved away. It is important to make the horizontal cut the second cut; if you wait to make this cut last, the entire weight of the wall section will come to rest on your chain saw blade, causing it to bind.
(4) Another option: Make two vertical cuts, and pull the wall back with hand tools. Click to enlarge
(5) The complete opening. Click to enlarge
Surprisingly, while working at this donated structure, we experienced some unusual chain binding during our downward cuts. Stepping inside the structure to see what the cause was, we saw nothing but the chain saw blade in wood. We removed the chain saw from the opening and began to peel back the wall with hand tools, to discover that the building was built around a chain-link fence! We had it the fence’s top rail while cutting. This did a number on the saw’s chain, which had to be replaced. The lesson learned: We never get to choose the building to which we respond to or its construction. Be prepared with back-up plans to accomplish your goal at all times.
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Subjects: Breaching a wall, truck company operations, RIT operations
