South Carolina CDL: Tanker Vehicles Practice Test

Not quite. The answer is closed before you drive the vehicle.

To help prevent leaks, close all manhole covers before you drive the vehicle.

Not quite. The answer is At the start of each trip and each time you stop

If you have a placarded trailer with dual tires, you should check the tires at the start of each trip and each time that you stop for any reason, whether to rest or to refuel. Use a tire pressure gauge to get an accurate reading.

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 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 Before loading it, driving it, or unloading it

You should inspect a tank vehicle before loading it, driving it, or unloading it. This is to ensure that it is safe to carry out these activities and the vehicle can safely hold its liquid or gas contents.

Not quite. The answer is may exceed legal weight limits.

A full tank of dense liquid (such as some acids) may exceed legal weight limits. For this reason, you may not be able to completely fill the tank with a dense liquid.

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 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.

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 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.

Not quite. The answer is The posted speed for a curve may be too fast for a tank vehicle.

Tank vehicles have a high center of gravity. 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 liquids or gases.

According to federal regulations, you need a tank endorsement to drive a tank vehicle that requires you to have a CDL. A tank vehicle is defined as a commercial motor vehicle that transports a bulk cargo of liquid or gas within one or more tanks that are either permanently or temporarily attached to the vehicle. [49 CFR 383.5],

Source: 49 CFR 383.93

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 250 feet.

You should always be able to stop within the distance you can see ahead. Fog, rain, or other conditions may require that you slow down to be able to stop in the distance you can see. If your headlights let you see only 250 feet ahead, adjust your speed so that you can stop within that distance. Otherwise, by the time you notice a hazard ahead, you may not be able to stop in time to avoid it.

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 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 Both of the above

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. The high center of gravity increases the risk of a rollover. And the liquid surge can push the vehicle dangerously forward or sideways, which can also cause a rollover.

Not quite. The answer is both of the above are true.

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. Also, some liquids are so dense that a full load may exceed the legal weight limit. For these reasons, you may not be able to fill your tanks completely.

Not quite. The answer is are bulk containers that are not permanently attached to a vehicle.

A portable tank is bulk packaging that is not permanently attached to a vehicle. The tank is loaded or unloaded while it is off the vehicle. Then the tank is put on the vehicle for transportation. Hence, the portable tank must show the owner or lessee's name. "Bulk packaging" means that the tank's capacity is more than 450 L (119 gallons) of liquid, or more than 454 kg (1,000 pounds) of gas. Some portable tanks have a capacity of 25,000 L (6,600 gallons).

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

Baffled tanks have bulkheads with holes to reduce forward-and-backward surge. This will reduce the chance that forward surge will push your vehicle dangerously forward when you're slowing or stopping. However, these bulkheads don't significantly reduce side-to-side surge, so rollovers can still occur.