Air Brakes #2

Air Brakes Endorsement Test | Iowa 2026 #2 Page 3 of 4

Train for FREE online with our Iowa CDL air brake test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a IA Class A/Class B driver license in 2026, practice as much as.. Read More

Train for FREE online with our Iowa CDL air brake test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a IA Class A/Class B driver license in 2026, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that the requirements for CDL may vary from state to state.

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13 . When parked on a flat surface, you should:

When parking on a level surface, you should use wheel chocks. If the vehicle is not equipped with spring brakes, this is essential to prevent the trailer from moving.

14 . Do not operate a vehicle if any brake drums have cracks that are larger than ____ of the width of the friction area.

Before beginning a trip, it is important to check the brake drums during your walk-around inspection. It is unsafe to drive if any brake drum has a crack more than one half of the width of the friction area.

15 . While driving, ____ generally holds spring brakes in place.

While driving, spring brakes are generally held in place by air pressure. If the air pressure gets low enough, the springs will activate the brakes.

16 . When parking, you should not use the parking brake if:

If your brakes are hot after coming down a steep grade, you should not use your parking brake when parking. Let your brakes cool before applying the parking brake or risk damaging the brakes.

17 . In a vehicle with dual parking control valves, a separate air tank can be used:

In a vehicle with dual parking control valves, there is a separate air tank that can be used to temporarily release the spring brakes if they have been activated due to low air pressure. Pushing in the proper control will release the spring brakes for a short period of time, allowing the driver to move the vehicle in an emergency.

18 . What kind of force do emergency brakes use?

Air brakes are really three different braking systems: the service brake, the parking brake, and the emergency brake. Emergency and parking brakes are applied with mechanical force.

See the exact questions that will be on the 2026 Iowa DMV exam.

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2026 Iowa | Frequently Asked Questions

To acquire a CDL Hazmat endorsement in Iowa, you need to pass the Hazardous Materials Endorsement Knowledge Test. Additionally, you must undergo a federal background check and fingerprinting. The TSA will assess your application and once approved, the Iowa Department of Transportation will add the endorsement to your CDL.
To obtain a CDL Hazmat license, you must first possess a valid Commercial Driver's License (CDL). You also need to be at least 21 years old, a U.S. citizen or have legal status, and be able to read and speak English. Additionally, you must pass the Hazardous Materials Endorsement Knowledge Test and undergo a federal background check and fingerprinting.
When applying for a CDL Hazmat endorsement in Iowa, you'll need to provide proof of U.S. citizenship or permanent residency, proof of identity, and proof of Iowa residency. Additionally, you'll need to bring your current CDL. A TSA background check and fingerprinting are also required, for which separate documentation may be needed.
Yes, there is a dedicated written test for the CDL Hazmat endorsement. This test is called the Hazardous Materials Endorsement Knowledge Test. It covers topics such as loading and unloading hazardous materials, bulk packaging marking, driving and parking rules, and emergency response procedures.
The written test for the CDL Hazmat endorsement in Iowa covers a wide range of subjects. These include understanding hazardous materials regulations, safety procedures, proper use of shipping papers, placarding, loading/unloading, bulk packaging marking, compatibility and segregation of cargo, and emergency response procedures.
Yes, there are additional fees associated with obtaining a CDL Hazmat endorsement in Iowa. These include a fee for the knowledge test, a fee for fingerprinting, and a fee for the TSA background check. The specific amounts can vary, so it's best to check with the Iowa Department of Transportation for the most current costs.
Yes, obtaining a CDL Hazmat endorsement in Iowa requires a background check. The Transportation Security Administration (TSA) conducts this check, which includes a review of your criminal, immigration, and FBI records. This ensures that you do not pose a security threat while transporting hazardous materials.
Yes, specialized training is required for the CDL Hazmat endorsement in Iowa. This involves understanding hazardous materials regulations, emergency response procedures, and safety protocols. After training, you must pass a written test to get certified. This ensures that drivers are equipped with necessary knowledge to handle hazardous materials safely.
No, you cannot legally transport hazardous materials in Iowa without a valid CDL Hazmat endorsement. This endorsement is required by federal law and ensures that drivers have the necessary knowledge and skills to safely transport hazardous materials. Violating this requirement can result in severe penalties, including fines and suspension of your CDL.
You can add a Hazmat endorsement to your current CDL in Iowa. You don't need to apply for a new CDL. However, you must pass a written test on hazardous materials and complete a TSA security threat assessment, which includes fingerprinting and a background check, to obtain the endorsement.

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See the exact questions that will be on the 2026 Iowa DMV exam.