Alabama CDL: Tanker Vehicles Practice Test

Not quite. The answer is Get out of your vehicle and away from the tracks.

If your vehicle gets stuck on a railroad track, get everyone including yourself out of your vehicle. Have everyone walk at about a 45-degree angle to the tracks in the direction from which you expect a train to approach. That way, if your vehicle is hit, none of you will be struck by flying debris. Once you've reached a safe location, call 911 or the telephone number on the railroad crossing sign.

Not quite. The answer is the distance you can see ahead.

No matter what type of motor vehicle you are driving at night (even a passenger car), you must drive at a speed that lets you stop within the range of your headlights. (In the dark, you have no way of knowing what lies beyond the reach of your headlights.) With low beams, you can see ahead only about 250 feet. Yet if you're driving a vehicle with air brakes at 45 mph, your vehicle's stopping distance may be as long as 346 feet. Hence, with low beams at 45 mph, you will not be able to brake in time to avoid a hazard that you see.

Not quite. The answer is you have to press the brake pedal harder than usual to control your speed.

If your brakes begin to fade, you'll notice that you have to depress the brake pedal harder to achieve the same braking effect as before. If your vehicle is so equipped, check the application pressure gauge to see just how much pedal effort you are employing. If the brakes continue to fade, you may not be able to slow down or stop at all.

Not quite. The answer is There will be less front-to-back surge than in a tank without baffles.

A baffled tank has bulkheads with holes through which the liquid can flow forward or backward but with less force than if there were no baffles. This will reduce forward-and-backward surge, making it less likely that surge will push your vehicle forward when you try to stop.

Not quite. The answer is You will continue in a straight line and keep moving forward no matter how you steer.

In a front-wheel skid, the front end of your vehicle tends to travel in a straight line regardless of how you turn the steering wheel. This type of skid is most often caused by driving too fast for the current driving conditions. Therefore, the best way to recover from this type of skid is to just let the vehicle slow down. Steer and brake only gently.

Not quite. The answer is with holes that let liquid flow through.

Tank baffles are bulkheads with holes through which the liquid can flow, but with less force than in tanks without such baffles. These baffles significantly reduce forward-and-backward surge but not side-to-side surge, so the risk of surge causing a rollover remains.

Not quite. The answer is leaks.

When you inspect your tank vehicle, the most important thing to check for is leaking tanks. It is illegal to knowingly carry liquids or gases in a leaking tank. Check around and underneath the vehicle for any signs of leaks. Also check all tanks, hoses, pipes, and connections for leaks.

Not quite. The answer is 9,000 gallons.

The average capacity of a DOT-406 or MC-306 fuel delivery truck (often called a "gasoline truck") is 9,000 gallons.

Not quite. The answer is Inspect the vehicle.

Before loading, unloading, or driving a tanker, you must inspect the vehicle. This makes sure that the vehicle is safe to carry liquids or gases and is safe to drive. Tank vehicles have special items that you need to check. Study the vehicle's operator manual to learn how to inspect your tank vehicle.

Not quite. The answer is the type of liquid.

Different liquids expand at different rates as the temperature increases. In science, the percentage increase of expansion for a given change in temperature is called the coefficient of thermal expansion. This value depends on the type of liquid. You need to find out the likely percentage increase for the type of liquid you'll be hauling, and allow enough room (called outage) for the expansion to take place.

Not quite. The answer is Wet roads can double the stopping distance at any speed.

To control surge, know the stopping distance of your vehicle and brake far in advance of a stop whenever possible. Bear in mind that your vehicle's stopping distance on wet roads will be about double its stopping distance on dry roads.

Not quite. The answer is side-to-side surge.

Some tanks have baffles: bulkheads with holes through which the liquid can flow forward or backward. These baffles significantly reduce forward-and-backward surge but not side-to-side surge, so the risk of surge causing a rollover remains.

Not quite. The answer is distribution of weight.

If the tank is divided into several smaller tanks (compartments) by bulkheads, pay attention to the distribution of weight whenever you load or unload these tanks. Avoid putting too much weight on the front or the back of your vehicle.

Not quite. The answer is You should not apply the brakes while turning.

To avoid a crash or other hazard, keep both hands on the steering wheel so you can turn as quickly as possible. However, turn just enough to avoid the hazard. A too-sharp turn risks a skid or rollover. While turning quickly, avoid braking. Braking in a turn can easily lock the wheels and cause a skid.

Not quite. The answer is the top of the tank

In general, the Maximum Allowable Working Pressure (MAWP) of a pressurized tank is the maximum pressure that the weakest part of the tank can handle in normal operation. For a cargo tank on a motor vehicle, the federal definition of MAWP assumes that the weakest part is at the top of the tank.

Source: 49 CFR 178.320

Not quite. The answer is roll over.

Baffled tanks can control back-and-forth surge but not side-to-side surge. During sudden steering changes, side-to-side surge can cause your tanker to roll over. Avoid such sudden moves when possible.

Not quite. The answer is surging.

When a tank is not completely filled, the liquid has room to move around. It can slosh back and forth or side to side. This is called surging.

Not quite. The answer is stop braking, turn quickly, and countersteer.

To recover from a drive-wheel braking skid, first stop braking. The rear wheels will unlock and roll again so there will be no more tendency to slide sideways. Then quickly steer your vehicle back on course. You may find that your vehicle will overshoot and keep on turning, possibly skidding in the opposite direction. Countersteer to counteract this. Note: This technique takes some practice. You should become proficient in it before you actually need to use it.

Not quite. The answer is some liquids expand more than others when they get warm.

Different liquids expand at different rates as the temperature increases. In science, the percentage increase of expansion for a given change in temperature is called the coefficient of thermal expansion. This value depends on the type of liquid. You need to find out how much outage you will need to allow for the type of liquid you'll be hauling.

Not quite. The answer is can affect the handling of your vehicle.

Liquid surge can greatly affect your vehicle's handling. Surge can push the vehicle in the same direction as the surge. This can be especially hazardous on icy roads, where a truck may be pushed forward a dangerous amount, maybe past a red light into an intersection. On curves, side-to-side surge can cause a rollover even when traction is good.