- Pre-Trip Inspection Tractor Trailer
- Driving Safely
- Transporting Cargo Safely
- Transporting Passengers
- Air Brakes
- Combination Vehicles
- Doubles and Triples
- Tank Vehicles
- Hazardous Materials
- School Buses
Section 3: Transporting Cargo Safely
This section tells you about hauling cargo safely. You must understand basic cargo safety rules to get a CDL.
If you load cargo wrong or do not secure it, it can be a danger to others and yourself. Loose cargo that falls off a vehicle can cause traffic problems and others could be hurt or killed. Loose cargo could hurt or kill you during a quick stop or crash. Your vehicle could be damaged by an overload. Steering could be affected by how a vehicle is loaded, making it more difficult to control the vehicle.
Whether or not you load and secure the cargo yourself, you are responsible for:
• Inspecting your cargo.
• Recognizing overloads and poorly balanced weight.
• Knowing your cargo is properly secured.
These are discussed below.
If you intend to carry hazardous material that requires placards on your vehicle, you will also have to have a hazardous materials endorsement. Section 9 of this manual has the information you need to pass the hazardous materials test.
This Section Covers
3.1 Inspecting Cargo
As part of your pre-trip inspection, make sure the truck is not overloaded and the cargo is balanced and secured properly.
Inspect the cargo and its securing devices again within 25 miles after beginning a trip. Make any adjustments needed. Check the cargo and securing devices as often as necessary during a trip to keep the load secure. A good habit is to inspect again:
• After you have driven for 3 hours or 150 miles.
• After every break you take during driving.
Federal, state, and local regulations for commercial vehicle weight, securing cargo, covering loads, and where you can drive large vehicles vary from place to place. Know the rules where you will be driving.
3.2 Weight and Balance
You are responsible for not being overloaded. definitions of weight you should know: Here are some
Definitions You Should Know
Gross Vehicle Weight (GVW). The total weight of a single vehicle plus its load.
Gross Combination Weight (GCW). The total weight of a powered unit plus trailer(s) plus the cargo.
Gross Vehicle Weight Rating (GVWR). The maximum GVW specified by the manufacturer for a single vehicle plus its load.
Gross Combination Weight Rating (GCWR). The maximum GCW specified by the manufacturer for a specific combination of vehicles plus its load.
Axle Weight. The weight transmitted to the ground by one axle or one set of axles.
Tire Load. The maximum safe weight a tire can carry at a specified pressure. This rating is stated on the side of each tire.
Suspension Systems. Suspension systems have a manufacturer's weight capacity rating.
Coupling Device Capacity. Coupling devices are rated for the maximum weight they can pull and/or carry.
Legal Weight Limits
You must keep weights within legal limits. States have maximums for GVWs, GCWs and axle weights. Often, maximum axle weights are set by a bridge formula. A bridge formula permits less maximum axle weight for axles that are closer together. This is to prevent overloading bridges and roadways.
Overloading can have bad effects on steering, braking, and speed control. Overloaded trucks have to go very slow on upgrades. Worse, they may gain too much speed on downgrades. Stopping distance increases. Brakes can fail when forced to work too hard.
During bad weather or in mountains, it may not be safe to operate at legal maximum weights. Take this into account before driving.
Don't Be Top-heavy
The height of the vehicle's center of gravity is very important for safe handling. A high center of gravity (cargo piled up high or heavy cargo on top) means you are more likely to tip over. It is most dangerous in curves or if you have to swerve to avoid a hazard. It is very important to distribute the cargo so it is as low as possible. Put the heaviest parts of the cargo under the lightest parts.
Balance the Weight
Poor weight balance can make vehicle handling unsafe. Too much weight on the steering axle can cause hard steering. It can damage the steering axle and tires. Underloaded front axles (caused by shifting weight too far to the rear) can make the steering axle weight too light to steer safely. Too little weight on the driving axles can cause poor traction. The drive wheels may spin easily. During bad weather, the truck may not be able to keep going. Weight that is loaded so there is a high center of gravity causes greater chance of rollover. On flat bed vehicles, there is also a greater chance that the load will shift to the side or fall off. Figure 3-1 shows examples of the right and wrong way to balance cargo weight.
Figure 3-1: Always load cargo the right way!
Test Your Knowledge
|These questions may be on your test. If you can't answer them all, re-read Sections 3.1 and 3.2.|
3.3 Securing Cargo
Blocking and Bracing
Blocking is used in the front, back, and/or sides of a piece of cargo to keep it from sliding. Blocking is shaped to fit snugly against cargo. It is secured to the cargo deck to prevent cargo movement. Bracing is also used to prevent movement of cargo. Bracing goes from the upper part of the cargo to the floor and/or walls of the cargo compartment.
On flatbed trailers or trailers without sides, cargo must be secured to keep it from shifting or falling off. In closed vans, tiedowns can also be important to prevent cargo shifting that may affect the handling of the vehicle. Tiedowns must be of the proper type and proper strength. The combined strength of all cargo tiedowns must be strong enough to lift one and one-half times the weight of the piece of cargo tied down. Proper tiedown equipment must be used, including ropes, straps, chains, and tensioning devices (winches, ratchets, clinching components). Tiedowns must be attached to the vehicle correctly (hook, bolt, rails, rings).
Cargo should have at least one tiedown for each ten feet of cargo. Make sure you have enough tiedowns to meet this need. No matter how small the cargo, it should have at least two tiedowns holding it.
There are special requirements for securing various heavy pieces of metal. Find out what they are if you are to carry such loads.
Front end header boards ("headache racks") protect you from your cargo in case of a crash or emergency stop. Make sure the front end structure is in good condition. The front end structure should block the forward movement of any cargo you carry.
There are two basic reasons for covering cargo, (1) to protect people from spilled cargo, and (2) to protect the cargo from weather. Spill protection is a safety requirement in many states. Be familiar with the laws in the states you drive in.
You should look at your cargo covers in the mirrors from time to time while driving. A flapping cover can tear loose, uncovering the cargo, and possibly block your view or someone else's.
You cannot inspect sealed loads, but you should check that you don't exceed gross weight and axle weight limits.
Sealed and Containerized Loads
Containerized loads generally are used when freight is carried part way by rail or ship. Delivery by truck occurs at the beginning and/or end of the journey. Some containers have their own tiedown devices or locks that attach directly to a special frame. Others have to be loaded onto flat bed trailers. They must be properly secured just like any other cargo.
3.4 Other Cargo Needing Special Attention
Dry bulk tanks require special care because they often have a high center of gravity, and the load can shift. Be extremely cautious (slow and careful) going around curves and making sharp turns.
Hanging meat (suspended beef, pork, lamb) in a refrigerated truck can be a very unstable load with a high center of gravity. Particular caution is needed on sharp curves such as off ramps and on ramps. Go slow.
Livestock can move around in a trailer, causing unsafe handling. With less than a full load, use false bulkheads to keep livestock bunched together. Even when bunched, special care is necessary because livestock can lean on curves. This shifts the center of gravity and makes rollover more likely.
Over-length, over-width, and/or overweight loads require special transit permits. Driving is usually limited to certain times. Special equipment may be necessary such as "wide load" signs, flashing lights, flags, etc. Such loads may require a police escort or pilot vehicles bearing warning signs and/or flashing lights. These special loads require special driving care.
Test Your Knowledge
|These questions may be on your test. If you can't answer them all, re-read Sections 3.3 and 3.4.|