By PAUL HASENMEIER
School bus accidents con-tinue to happen across our country, creating challenging rescues for emergency responders. An average of 10 student fatalities occur each year in school bus crashes, but there are many more injuries that need attention. Extrication techniques to remove windows, windshields, and doors on school buses are considered more basic, but they, too, require additional training in addition to what you have learned in fire school. When a bus rolls over, hits another bus, or crashes into another large vehicle, advanced extrication techniques may be necessary. Similar to accidents involving passenger cars, there may come a time when firefighters have to cut through the sidewall, roll a dash, flip the roof, or tunnel through the floor of a school bus. This article focuses on procedures to accomplish some of these advanced techniques.
OPENING THE SIDEWALL
School buses are built like tanks to protect our children. Lateral impact is a great concern during any crash, which is the reason the sidewall is reinforced from the floor level to just below the windows. A school bus’s outside skin is 20-gauge steel; the striped rub rails are of a slightly thicker steel. You can penetrate this steel with the spike of a halligan, producing a purchase point for a pneumatic chisel (photo 1). If you don’t have a reciprocating saw to cut the skin, you can also use a chisel. Behind the outer skin are wiring and a layer of insulation for thermal and sound absorption. The inner main structural members consist of 12-gauge vertical bows and 14-gauge lateral crash rails located above the bus floor. On newly constructed buses, the bows run from below the floor on one side and over the top; they end below the floor on the opposite side. These bows also create the posts between the windows. Lateral steel bracing between the posts is difficult to remove. Inside the main structural components is a finished lighter gauge steel or composite material.
(1) Photos by author unless otherwise noted.
Even after extensive training, you will find that accessing the sidewall can be time-consuming. The tool of choice for this job is the reciprocating saw. It is important to have various blade types and lengths and at least 25 spare blades.
Two options for successfully cutting through the sidewall follow.
1 After you remove the window and locate the patients, cut down the sidewall just inside the posts. Make your opening one or two windows wide, depending on the rescue’s needs. While you make the cuts, begin removing the bus seats. Do this with a ratchet set; a reciprocating saw; and, if room allows, hydraulic cutters and spreaders. If you use the spreaders to pop the seats, start along the sidewall first, then cut the posts along the aisle. The two cuts in the wall need to be down to the floor in most circumstances, but others may dictate an opening only to seat level (photo 2). If only one window width is being removed, you can bend the wall down without cutting along the floor. When a cut width of two windows wide is needed, cut the middle post to bend the wall down (photo 3). Use a halligan spike to create a purchase point, and cut the post.
2 Use the same techniques as option 1, but instead of stopping your cut at floor level, continue. With practice, a skilled reciprocating saw operator can cut a “U,” eliminating the entire sidewall section in one piece.
Some may consider other cutting options such as circular saws, cut-off grinders, or torches (which is not recommended). These tools are not intrinsically safe, throw many sparks, and are loud. Although reciprocating saws are also not intrinsically safe, they create less of a hazard than the previously mentioned tools. Remember, you don’t want to spark a fire or increase the external stress on a busload of passengers.
ROLLING THE DASH
If a significant frontal collision entraps the bus driver, you may have to roll the dash or the steering column. Techniques to roll a school bus dash are similar to those for passenger cars, with one major difference—size. Because of a school bus’s size, you can use other means to roll the dash. Hint: Call for a heavy wrecker as soon as you determine if any extrication is needed.
If the driver is trapped behind the wheel, your first step is to remove the front windshield by pulling the rubber seal. Using a heavy wrecker is one way to get the dash off the driver. Back up the wrecker to the bus until its rear push bar is against the bus’s front bumper, then extend and lower the lifting boom above the engine compartment for a conventional (type C) bus or just outside the front windshield for a flat-nosed (type D) bus (photo 4).
Next, wrap a chain around the steering column and secure it back to the lifting boom’s hooks (photo 5). No relief cuts are necessary, but make sure the materials are moving away from the driver during the lift.
Tension the chain, lift slowly, and rapidly extricate the driver once space is provided. Remember to slack the chain as soon as possible. This procedure, if set up correctly and tensioned slowly, will not shake or bounce the school bus (photos 6, 7) before and after a dash roll.
You can revert to old-school methods of rolling the dash if the heavy wrecker is not yet on scene. You may be able to use hydraulic cutters, spreaders, and rams to make enough room to extricate the driver. If a full dash roll is needed, fully open the spreaders and lay them on the hood of a conventional bus, extend a chain from one tip to the underside frame, and extend another chain from the other spreader tip and wrap it around the steering column. Slowly tension the chains and roll the dash.
Rolling the dash of a flat-nose bus is a little more challenging because there is no hood on which to rest the spreaders. You will need block cribbing to keep the spreaders off the grill and establish a better angle for the tool to pull.
Chain placement is the same as for a conventional bus. If the passenger-side A post, main entrance door, and roof are crumpled down on the driver or other passengers, you may have to gain access through the sidewall at the driver’s window. However, you still might have to roll the dash to create an opening for removing the victim (photos 8, 9).
FLIPPING THE ROOF
In a vehicle crash that crumples the roof down on its occupants, removing—or flipping—the roof can be a lifesaving operation; the possibility of doing this for a school bus may be rare, but it carries the same importance as that of a passenger car. You might have to use your imagination to devise a scenario that would require the roof to be flipped on a school bus. Again, having a heavy wrecker on scene will be of great benefit.
Damage and occupant location will determine the complexity and the portion of the roof to be flipped. A heavy wrecker will facilitate the lifting process. Before the lift, firefighters will usually cut the A (low), B (high), C (high), and D (high) posts on both sides of a bus with the plan to hinge at the E post. Relief cuts can be made at the E post if personnel and tools are available, but this is not mandatory (photo 10). Remove the front windshield by pulling the rubber gasket; remove the windows or at least cut the frames to prevent resistance.
Position the wrecker with the rear push bar against the school bus’s front bumper and the extension boom lowered to just above the windshield. If the wrecker doesn’t have a rear push bar, then chain and tension the front bumper of the bus to the rear jacks of the wrecker (photo 11). Loop a chain through the bus and back to the wrecker’s extension boom (photo 12). It may seem that this procedure might create excess movement for already injured passengers, but with the wrecker operator’s steady hand, a smooth roof lift is possible (photo 13).
If a wrecker is not available, you can still cut the A, B, C, and D posts; remove the windshield and windows; and hinge the roof at the E post. Using a come-along that is secured toward the rear of the bus and making an elevated cribbing platform for the come-along to sit on will produce a working angle sufficient to lift the roof upward and off the victims.
TUNNEL THROUGH THE FLOOR
Scenario: A school bus has rolled over and crashed into a bridge abutment, preventing basic access through windows and doors. To establish an efficient flow of patient removal and rescuer movement, cut two openings. As a last resort, cut an opening through the school bus floor.
Floor joists, fuel tanks, drive shafts, and large battery banks in hybrid-powered buses are obstacles underneath a school bus (photo 14). The school bus floor interior has a layer of rubber and plywood over the 14-gauge sheet metal and seats secured with bolts that you must remove (photo 15). Creating an opening large enough to pass patients on backboards through is another time-consuming and personnel-taxing operation. Be sure to make inspection holes or visually confirm that no patients are in the path of the reciprocating saw.
No one wants to be involved with a serious school bus crash, but these wrecks happen daily. In these incidents, scene management, basic procedures, and advanced extrication techniques should begin immediately. Go to your local bus garage and examine what you will be up against, train with heavy wrecker operators, and get your hands on the tools.
PAUL HASENMEIER is a 10-year fire service veteran and a firefighter for the Huron (OH) Fire Department. He is a paramedic, a fire inspector, a scuba diver, and an instructor. He has an associate degree in fire science and is a member of Ohio’s Region 1 USAR team. Hasenmeier’s articles have been published in many fire service periodicals. He has presented at FDIC, the NY Fire Chiefs Conference, the Ohio Fire Chiefs Conference, the Ohio Association for Pupil Transportation Conference, the Ohio State Firefighters Association Conference, Fire Rescue Canada, the Fire Department Safety Officers Conference, and other regional and national training events.
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