Ohio CDL: Tanker Vehicles Practice Test

Not quite. The answer is Read the vehicle's manual to learn how to do it.

Tank vehicles come in many models and sizes, each with special items that you need to check during an inspection. Read the vehicle's manual to learn how to inspect it properly.

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 1,000 gallons or more.

Federal regulations define a "tank vehicle" as a commercial motor vehicle designed to transport liquids or gases within tanks that have an individual rated capacity of more than 119 gallons each and an aggregate rated capacity of 1,000 gallons or more. To drive such tank vehicles, you must have a Tank (N) endorsement or Combination Hazmat and Tank (X) endorsement on your CDL.

Source: 49 CFR § 383.5

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 There will be less front-to-back surge than in a smooth bore tank.

Bulkheads divide a tank into several smaller tanks. This will reduce forward-and-backward surge, making it less likely that surge will push your vehicle forward when you try to stop. However, when loading and unloading the smaller tanks, be sure to pay attention to weight distribution.

Not quite. The answer is can have strong forward-and-backward surge.

Baffles are often used in tanks to reduce forward-and-backward surge. Nevertheless, certain cargoes, such as milk and other liquid food products, must be transported in smooth bore, unbaffled tanks. (Sanitation regulations forbid the use of baffles because they are hard to keep sufficiently clean.) These tanks are liable to have very strong forward-and-backward surge. Be very careful when driving vehicles with such tanks.

Not quite. The answer is baffles.

Baffles are devices that regulate the flow of liquid. In a tank vehicle, baffles are a type of bulkhead with holes through which liquid may flow but with reduced force.

Not quite. The answer is MC-306 (DOT-406)

MC-306 (DOT-406) cargo tanks carry liquids under very low or no pressure (maximum allowable pressure of 3 psi for MC-306 and 4 psi for DOT-406). The cargo tank has an oval or elliptical cross section and is usually compartmented. These tanks are commonly used to carry gasoline, diesel fuel or fuel oil, and other flammable liquids.

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 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 there is an even distribution of weight.

Some liquid tanks are divided into several smaller tanks by bulkheads. When loading and unloading the smaller tanks, pay attention to weight distribution. Don’t put too much weight on the front or rear of the trailer.

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 Environment

The S.T.A.M.P.E.D. acronym is widely used to assist you in obtaining the correct hoses and fittings for your needs. S: the required size of the hose; T: the temperatures to which the hose will be subjected; A: the application (use) to which the hose will be put; M: the types of material (liquid, gas, etc.) that will have to flow through the hose; P: the maximum working pressure of the hose; E: the required fittings at the ends of the hose; D: the date at which the hose must be delivered to you.

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 5 mph slower.

On a steep downgrade, don't keep applying your brakes continuously because this might cause them to fade (become less effective). Instead, apply your brakes sparingly as a supplement to engine braking. Select a "safe" speed. Let your vehicle reach this speed. Brake gently until you are going 5 mph slower. Then let your speed increase back to the "safe" speed. Keep varying your speed up and down this way. This technique is known as snub braking or snubbing.

Not quite. The answer is Watch gauges and mirrors and use your senses to check for problems.

During your trip, you should be watching a number of things, such as your mirrors, gauges, instruments, lights, tires, and cargo. Use several of your senses – sight, hearing, smell, and feel – to detect possible trouble.

Not quite. The answer is You should avoid traveling alongside other vehicles whenever possible.

Whenever another vehicle is traveling alongside yours, there's always a chance that the vehicle might try to move into your lane and accidentally hit your vehicle. Also, the vehicle is blocking you from changing lanes. It's safer to find an open spot where there are no vehicles on either side of you. (Of course, that may not be possible in heavy, congested traffic.)

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 should avoid braking as you're turning.

The liquid cargo can surge both back and forth and side to side. This makes a skid more likely if you brake in a sharp turn. And it also makes it more likely that the skid will lead to a rollover.

Not quite. The answer is speed up slightly

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.