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Flashcards in Chapter 9: Commercial/ Heavy Vehicles Deck (89)
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Medium trucks weigh between ____ and ____ pounds. Common examples are ____ and ____.

* 13,000 and 33,000
* local delivery trucks and garbage trucks


Heavy trucks in the U.S. are defined as weighting ____

more than 33,000 pounds


What is the most common type of truck?

Straight truck (ex. delivery truck)


Traits of straight trucks:

* 2 or 3 axles, all attached to 1 frame.
* Gross vehicle weight between 10,000 and 40,000 pounds
* large boxy bodies
* often used as delivery vehicles
* may have flatbeds or large box bodies mounted to their frames.


A ____ mounted on motorized tractors, serves as the attachment point for a semitrailer.

fifth wheel device


The entire truck and semitrailer combination may weigh up to ____

140,000 pounds


The tractors in tractor trailer combo's may have ____ axles and may weight up to ____ pounds.

* 2 or 3
* 18,000 pounds


Tractor trailer combos can carry up to ____ of hazardous materials.

440 pounds



Diamond-shaped sign that is affixed to each side of a structure or a vehicle transporting hazardous materials to inform responders of fire hazards, life hazards, special hazards, and reactivity potential. The placard indicates the primary class of the material and, in some cases, the exact material being transported.


Two most common types of cabs are:

* conventional
* cab-over units


During extrication operations on trucks with air ride cabs, rescuers must ____.

crib between the frame and cab so if the air bleeds off the trucks cab, it does not lower and hinder extrication. Also capture the cab with chains or straps and isolate the power to secure the cab from any hazard if the air ride suspension were to inadvertently fill.


On a cab over unit, where is the cab generally attached to the chassis?

In the center behind the cab (latch point), and by hinge at the front of each frame rail.


Rescuers access the sleeper unit by ____

forcing entry through the required exterior door


Sleepers that are separate units must have ____

an intercom between the sleeper and the cab.


Often team drivers will have a sign indicating the driving team on the ____

driver door area



An auxiliary structure or the external surface either attached to, or a part of the roof of a large truck that serves to reduce drag.


The cab roofs of most medium and heavy trucks are usually covered with the ____ on the vehicle, and is supported by ____.

* lightest gauge metal or fiberglass
* two or more ribs running from front to rear.


All trailers are one of two basic styles:

* trailers or semitrailers


A trailer is a ____ unit with wheels ____.

* freestanding
* front and rear
* The front axle on a trailer is connected to a turntable that turns from side to side for better tracking. A trailer couples to a tractor of another trailer with a long tow bar, often called a dolly.


Semitrailers have wheels ____ and is supported by ____.

* only in the rear
* the tractor when locked into a fifth wheel, or by a pair of small wheels known as landing gear, that are attached to the underside of the trailer by two struts.


When not in use, a semi-trailers landing gear can be lowered by a hand crank that has two speeds:

* Push in and crank for slow raising or lowering
* Pull out and crank for fast raising or lowering


Some trailers are equipped with sliding axels that are used to ____

* manage trailer loads
* improve close quarters maneuverability
* or allow loading and unloading of the trailer.


Low-load bed trailers and heavy equipment trailers often have a powered system to ____

slide entire axle assemblies along the track or frame rails of the low slung trailer. This action lowers one end or the trailer to the ground to drive the equipment, loading and unloading the trailer.


The person charged with securing moveable trailer axles should ____

check each individual lock pin


Some trailers are also equipped with air suspension systems, Rescuers should ____ when stabilizing these trailers.

crib the trailer box or bed to the frame to prevent movement if suspension air is lost.


The ____ of a box trailer is the area most easily penetrated because the covering material is thinnest and there are the fewest structural members.



Tanker trailer capacities can range from ____ to ____

200 to 14,000 gallons


Lowboy trailer (AKA heavy duty trailers)

Trailers that feature a low center deck area designed to carry large, heavy loads up to several hundred tons. These trailers often have two or three rear axels, all with dual tires on each hub, and can have additional sections with multiple axels to support especially heavy loads. Loads may be over 175 feet long and/or over width (greater than 8 feet). These trailers may overwhelm resources due to the large volume of material needed to stabilize them.


The ____ and/or ____ provides the best points on medium and heavy trucks to perform stabilization.

frame and chassis


Truck batteries are either ____ or ____ systems supplied by ____ batteries. These batteries may be located ____

* 12 or 24 volt
* one or more banks
* in more than one location on the truck