School Bus Extrication - Part 1: Our Precious Cargo
David Pease, Carolina Fire/Rescue/EMS Journal
One of your next determinations will be to see if extrication will be necessary. If so, then an extrication team would need to be established with a Safety Officer and Operations Officer. The plan of action would need to be laid out and followed. We will talk more about the extrication aspect in the next article.
Let us take a look at how most school buses are constructed. One of the largest bus manufacturers is located in High Point, North Carolina. Thomas Built Buses, Inc. offers seven different wheelbases and fifteen body sizes. These buses range from thirty-five passenger to seventy-seven passengers. School buses are classified into four basic types. Type “A” buses are basically large passenger vans with either gross weights of more than 10,000 pounds or less than 10,000 pounds. The entry door is behind the front wheel and this bus has a driver’s door. Type “B” buses are larger with a GVWR of greater than 10,000 pounds and has the entry door behind the front wheelbase. These buses typically do not have a drivers side door and the engine is forward of the windshield. This might sometimes be called the “short bus”. Your typical school buses are classified as type “C” buses. These buses are longer, have a GVWR greater than 10,000 pounds, and the entry door is again behind the front wheel. There is no driver’s door. The final type “D” bus is the longer, coach type bus. This bus has a boxy appearance, and the entry door is in front of the front wheel. The engine may be located in the front, middle section, or the rear of the bus.
Next, we will take a look at some of the particular features that are found on buses. The entry doors in the type “A” and “B” buses are usually your standard type doors and found in most vehicles, with standard hinges and a nader pin. The passenger side doors on these buses may be redesigned to fit the needs of the owner or operator of the bus. In most cases the windows on these doors will not operate. The doors on the type “C” and “D” buses may vary some. Some buses have a split type door that in most cases opens to the outside. Other buses may have a hinged type door that folds back or forward, depending on the manufacturer. Most of these doors are operated by a pivot arm extending to the driver. When these doors are in the open position, the workable opening in 22 inches to 24 inches across, and 68 inches to 72 inches in height. You may also encounter school buses that use an air control mechanism to operate the entry doors. The control switch is normally located to the right on the console and a secondary emergency release switch in the stairwell of the entry door.
The other type of doors you will encounter are the emergency exit doors. These are usually located in the rear of the bus, depending on the design and type. On type “A” buses these doors may be double doors like those found in a typical delivery van. On your larger buses the emergency exit doors are usually a large door found in the rear of the bus. These doors have no locking mechanism, so they cannot be accidentally locked. These doors are for the emergency exit of children when the front door cannot be used or quick evacuation through both doors is required. These doors open outward and can be opened from the inside or from the outside. The doors are hinged and have either a one or three point type latching system. The single latching system is the same as your typical vehicle, while the three-point latch system allows for the door to be secured at the top and bottom.