Question 1

What is the primary difference between a 'Smooth Bore' tank and a 'Baffled' tank?

Accepted Answer

Smooth bore tanks (often used for food grade milk or sanitation) have no internal dividers (baffles), allowing liquid to surge violently from front to back.

Question 2

What is a 'Baffle' in a tanker?

Accepted Answer

Baffles are internal walls with holes in them. They let liquid flow between sections but slow down the front-to-back surge (sloshing) of the liquid.

Question 3

A 'Bulkhead' in a tanker refers to:

Accepted Answer

Bulkheads are solid walls that create separate, liquid-tight compartments within a single tank trailer, allowing different products to be carried at once.

Question 4

Why do 'Smooth Bore' tanks have stronger forward-and-back surge than baffled tanks?

Accepted Answer

Without baffles to interrupt the flow, the liquid wave can build up speed and force as it travels the full length of the tank.

Question 5

What is 'Outage'?

Accepted Answer

Outage (or ullage) is the space left empty at the top of the tank. Liquids expand when they get warm; without outage, the tank could burst.

Question 6

You are driving a tanker carrying a dense liquid (like acid). Why must you be careful not to fill it completely?

Accepted Answer

Dense liquids weigh more per gallon. A tank filled to capacity with a heavy liquid will often exceed legal axle weight limits.

Question 7

Baffles in liquid cargo tanks do not prevent which type of surge?

Accepted Answer

Baffles typically run across the width of the tank to stop forward/backward motion. They do very little to stop side-to-side surge, which can cause rollovers in curves.

Question 8

Food grade products (like milk) are usually transported in:

Accepted Answer

Milk tankers are usually smooth bore because baffles are difficult to clean and sanitize properly (bacteria hides in the corners).

Question 9

Why do tankers have a higher center of gravity than standard vans?

Accepted Answer

Most of the weight (the liquid) is carried high off the ground, making the vehicle more top-heavy and prone to rolling over.

Question 10

What is the purpose of a 'Manhole Cover' on a tanker?

Accepted Answer

Manhole covers allow human access to the tank. They must be fitted with gaskets and closed tightly to prevent leaks.

Question 11

Cargo tanks carrying hazardous materials must have:

Accepted Answer

Hazmat tankers must be equipped with remotely operated emergency shutoff valves to stop the flow of liquid in case of an accident or leak.

Question 12

Which type of tank is generally the most stable to drive?

Accepted Answer

A fully loaded tank is more stable than a partially loaded one because there is no room for the liquid to surge (slosh) around.

Question 13

What is the danger of a 'partial load' in a smooth bore tank?

Accepted Answer

Partial loads allow the liquid to move freely. In a smooth bore tank, this creates a powerful 'liquid hammer' effect that can push a stopped truck into an intersection.

Question 14

If you are hauling liquids in a tanker with compartments, and you are unloading at multiple stops, you should:

Accepted Answer

Unloading must be planned to maintain stability. Unloading only the front or rear can make the trailer unstable or overload the remaining axles.

Question 15

A 'Specification Tank' is a tank that:

Accepted Answer

Hazmat must be transported in 'Spec Tanks' (e.g., DOT 406, 407, 412) designed and certified to withstand pressure, impacts, and leaks.

Question 16

When inspecting a tanker, you should pay special attention to:

Accepted Answer

The tank shell is the containment vessel. Dents or cracks can lead to catastrophic failure under pressure or load.

Question 17

The amount of liquid to load into a tank depends on:

Accepted Answer

You must calculate the load based on expansion (outage), density (weight limits), and tank capacity.

Question 18

A DOT 406 (MC 306) cargo tank is typically used for:

Accepted Answer

DOT 406 tanks are the standard oval-shaped aluminum tankers used for gasoline and diesel.

Question 19

A DOT 407 (MC 307) cargo tank is typically:

Accepted Answer

DOT 407 tankers are versatile, low-pressure stainless steel tanks used for chemicals, solvents, and mild corrosives.

Question 20

A DOT 412 (MC 312) cargo tank is easily identified by:

Accepted Answer

DOT 412 tanks carry heavy corrosives (acids). They are narrow cylinders with visible external stiffening rings.

Question 21

What is a 'MC 331' tank used for?

Accepted Answer

MC 331 tanks are high-pressure steel tanks with rounded ends (capsule shape), used for liquefied gases like propane.

Question 22

If a tanker has leakage from a valve or connection, you should:

Accepted Answer

Leaks are serious. If it's a loose fitting, you may tighten it if trained/safe. Otherwise, the vehicle is out of service.

Question 23

The vents on a tanker are designed to:

Accepted Answer

Vents allow the tank to 'breathe'. Without them, pumping liquid out would create a vacuum that could implode the tank, and heat expansion could explode it.

Question 24

When checking the pipes, connections, and hoses of a tanker, you are looking for:

Accepted Answer

The entire containment system (tank + plumbing) must be inspected for integrity.

Question 25

A tanker carrying a liquid that expands significantly with heat (like gasoline) needs:

Accepted Answer

Materials with high coefficients of expansion require more outage (empty space) to prevent overflow or tank rupture as they warm up.

Question 26

Portable tanks (like ISO tanks) are:

Accepted Answer

Portable tanks are bulk containers (often mounted in a frame) that can be loaded onto flatbeds or skeletal trailers. They must be secured with twist locks.

Question 27

Which part of the tanker protects the fittings on top of the tank in case of a rollover?

Accepted Answer

Tankers have rollover protection structures (metal rails or cages) on top to prevent the manholes and valves from being sheared off if the truck flips.

Question 28

The internal walls in a tanker that have holes in them are called:

Accepted Answer

Baffles have holes to allow flow; bulkheads are solid.

Question 29

If a tanker has 'Double Bulkheads', there is usually a ____ between them.

Accepted Answer

Double bulkheads separate incompatible liquids. The void space between them allows leaks to drain to the ground rather than mixing with the other cargo.

Question 30

Fusible links on emergency shutoff valves are designed to:

Accepted Answer

Fusible links melt at a specific temperature (during a fire), releasing the spring tension and snapping the internal valve shut to stop the fuel source.

Tanker Vehicles Practice Questions

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