Tank

This endorsement is required to haul any liquid or gaseous materials in a tank or tanks having a capacity of 1,000 gallons or more that is either permanently or temporarily attached to the vehicle or.. Read More

This endorsement is required to haul any liquid or gaseous materials in a tank or tanks having a capacity of 1,000 gallons or more that is either permanently or temporarily attached to the vehicle or chassis. To receive this endorsement, applicants must pass a test. The test consists of 20 multiple choice questions. Each question has three possible answer choices. To pass, the applicant must answer at least 16 questions correctly. Test questions come from the Iowa Commercial Driver License Manual. Questions come from chapters covering: Driving Safely, Tank Vehicles, Hazardous Materials and Combination Vehicles. The Tank endorsement can be used with the Class A, B or C CDL.

Number of Question
Passing Score

8. If you must make a quick stop while transporting liquids, it may be a good idea to use the:

Explanation
A tank vehicle transporting liquids is less stable than other vehicles and may be prone to roll over or skid if not operated in a safe manner. If you must make a quick stop to avoid an accident while transporting liquid cargo, it may be a good idea to use the controlled braking method.

9. To use the stab braking method while transporting liquid cargo, you should apply the brakes:

Explanation
The stab braking method for emergency stops involves fully applying the brakes until they lock up. The brakes are then released until the wheels start rolling, and then the process is repeated.

10. If driving in extremely hot weather and the air pressure in your tires is too high, you should:

Explanation
Air expands as it gets warmer, so the air pressure in your tires could reach dangerously high levels while being driven in very hot weather. If this happens, stop and let your tires cool. Do not let air out of the tires, as this could result in the pressure dropping to an unsafe level once they cool down.

11. When driving under wet conditions, a lack of spray coming from the tires of other vehicles indicates that:

Explanation
In wet conditions, a lack of spray coming from the tires of other vehicles indicates that ice has formed on the road. Be especially cautious when traveling under wet conditions in freezing weather.

12. If an Anti-Locking Braking System (ABS) is not working on a truck:

Explanation
An Anti-Lock Braking System (ABS) is in place as an addition to a braking system. It intervenes to prevent brakes from locking up during hard braking. If ABS is not working, the basic braking functions on a vehicle will still remain, so the driver can continue to drive and brake normally.

13. Mirrors should be used:

Explanation
When driving, you should frequently check the mirrors on both sides of your vehicle.

14. What should you do if your vehicle gets stuck on railroad tracks?

Explanation
If your CMV gets stuck on railroad tracks, you should immediately leave the vehicle and get away from the tracks. Check the signposts or signal housing at the crossing for emergency contact information and call 911, or another appropriate emergency number.
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