Wisconsin CDL: Tanker Vehicles Practice Test

Not quite. The answer is partly engage the clutch before you take your right foot off the brake.

When you start your vehicle, avoid rolling backward or else you may hit someone behind you. Set the parking brake whenever necessary to keep from rolling back. Release the parking brake only when you have applied enough engine power to keep from rolling back. If you have a manual transmission vehicle, partly engage the clutch before you take your right foot off the brake. On a tractor-trailer equipped with a trailer brake hand valve, the hand valve can be applied to keep from rolling back. Some modern automated manual transmissions (AMT) have a Hill Start or Hill Assist feature. When the vehicle is in gear on an incline and the driver releases the service brakes, the AMT will prevent the vehicle from rolling back for about three seconds, giving you time to apply the accelerator.

Not quite. The answer is 70%

It takes special skills to operate a tank vehicle safely. About 70% of tank truck drivers haul hazardous materials, such as gasoline. Doing so takes even more special skills. Such drivers must obtain both a tank vehicle (N) endorsement and a hazardous materials (H) endorsement on their CDLs, or a combination tank vehicle and hazardous materials (X) endorsement.

Not quite. The answer is allowance for expansion of liquid.

When liquid heats up, it expands, and outage is the space in the tank that is allocated to handle the expansion. Different types of liquids expand by different amounts. Therefore, the amount of outage you will need depends on the type of liquid.

Not quite. The answer is Keep a steady foot on the brake and don't release the brake too soon.

To control the effects of surge, brake far in advance of a stop. Maintain steady pressure on the brakes and don't release them too soon.

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 use controlled or stab braking.

Sudden or hard braking can cause the liquid in the tank to surge forward, pushing your vehicle forward. If you must stop quickly, use controlled or stab braking instead. (However, don't use stab braking if your vehicle is equipped with antilock brakes.)

Not quite. The answer is You should not load a cargo tank completely full.

Some liquids expand significantly when they warm up. To fill a tank with such a liquid, you must leave some room in the tank (called "outage") to take the expansion. 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 a high center of gravity.

It takes special skills to drive a tanker carrying liquid cargo because of the vehicle's high center of gravity and the possibility that the liquid cargo may surge forward and backward or from side to side. Much of a loaded tanker's weight is carried five or six feet above the ground. This makes a tanker top-heavy, which makes it more prone to rollovers than other types of vehicles. Tests have shown that a tank vehicle can roll over at the speed limits posted for curves. The safest way to take a curve in a tanker is to slow down well below the posted speed limit before you enter the curve.

Not quite. The answer is If the wheels are skidding, you cannot control the vehicle.

In an emergency, avoid hard braking. Hard braking can lock the wheels, which may cause a skid and loss of control. Instead, use stab braking (unless your vehicle has antilock brakes) or controlled braking.

Not quite. The answer is 20 mph

If you've moved onto a shoulder that may have a loose surface, let your vehicle slow down to about 20 mph before you brake. Braking at a higher speed on a loose surface can cause a skid.

Not quite. The answer is Your brakes may fail because of water freezing.

Your air tanks hold a mixture of water and compressor oil. If left inside to collect at the bottom, the water may freeze and cause brake failure.

Not quite. The answer is driving too fast.

Over-braking and over-steering can cause skids. Both over-braking and over-steering are more likely when you're driving too fast for the current road conditions.

Not quite. The answer is Slow to a safe speed before entering, then accelerate slightly through the curve.

The posted speed for a curve may be safe for cars but not for tankers because of their relatively high center of gravity. Tests have shown that a tanker can roll over on a curve when traveling at the posted speed. The safest way to take a curve in a tanker is to slow down before the curve and then accelerate slightly through the curve. Braking in a curve risks a skid.

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 At the end of each working day

Oil and water can start to collect in the bottom of an air tank and can cause brake failure if it's not drained. Unless your vehicle automatically drains the air tanks, you should drain them at the end of each working day so the moisture and oil will not freeze or coagulate and cause your brakes to fail.

Not quite. The answer is Set the parking brake and pull forward gently.

The parking brake is meant to keep your vehicle from moving. The best way to test it is to apply the parking brake and then try to pull forward gently. The parking brake should hold your vehicle in place. If you're pulling one or more trailers, test each trailer's parking brakes in the same way.

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 You should avoid backing whenever you can.

Backing up a large vehicle is always dangerous, even with a helper. Try to avoid backing up as much as possible.

Not quite. The answer is individual tanks over 119 gallons or a total of at least 1,000 gallons.

You must have a tank vehicle (N) endorsement to drive a vehicle with one or more individual tanks over 119 gallons or multiple tanks totaling at least 1,000 gallons.

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.