Tanker and Hazmat are two separate endorsements, and you need both if you haul certain cargo

A tanker endorsement (Tank) and a hazmat endorsement (H) are not the same thing, and many drivers need both. The tanker endorsement means you can drive a truck with a large tank permanently attached to haul liquids or gases in bulk. The hazmat endorsement means you can transport materials the Department of Transportation classifies as hazardous — explosives, flammable liquids, poisons, radioactive materials, and others. A tank truck carrying drinking water needs only the tanker endorsement. A tank truck carrying gasoline needs both.

The confusion happens because tank trucks often carry hazardous materials, and hazmat materials often travel in tanks. But the endorsements test different knowledge. The tanker test covers tank vehicle handling, weight distribution, and emergency procedures specific to bulk liquid transport. The hazmat test covers material classification, shipping papers, placarding, and what to do if cargo spills or ignites. You take separate written tests for each one.

Key Takeaways

  • Tanker endorsement lets you drive a truck with a permanently mounted tank; hazmat endorsement lets you transport materials classified as hazardous by the Department of Transportation.
  • You need tanker endorsement to haul any bulk liquid or gas in a tank truck, regardless of what the cargo is.
  • You need hazmat endorsement to transport any hazardous material, whether it travels in a tank, box truck, or flatbed.
  • If you haul gasoline, propane, chemicals, or other regulated materials in a tank, you must pass both the tanker test and the hazmat test.
  • Each endorsement requires its own written test; you cannot pass one and assume you have the other.

When you need tanker endorsement alone

You need a tanker endorsement if your truck has a permanently attached tank and you haul any bulk liquid or gas — even if it is not hazardous. Examples include water, milk, juice, or food-grade oils. The tanker test focuses on the physics and safety of moving large volumes of liquid in a tank: how the cargo shifts during acceleration and braking, how to prevent rollover, how to manage weight distribution, and emergency procedures if the tank ruptures or leaks.

The tanker endorsement is required by law before you can legally operate a tank truck, regardless of cargo type. Some drivers haul only non-hazardous materials their entire career and never need the hazmat endorsement. But if you ever plan to haul gasoline, propane, chemicals, or any material on the Department of Transportation's hazardous materials list, you must add hazmat on top of tanker.

When you need hazmat endorsement alone

You need a hazmat endorsement if you transport any material classified as hazardous by the Department of Transportation, even if it does not travel in a tank. A box truck carrying fireworks, a flatbed carrying explosives, or a dry van carrying pesticides all require hazmat endorsement. The hazmat test covers material classification, shipping papers, placarding requirements (the diamond-shaped warning labels on the vehicle), and procedures for spills, fires, or accidents involving regulated cargo.

Many hazmat shipments do not use tank trucks. A driver hauling hazardous materials in a standard enclosed trailer or box truck needs hazmat endorsement but not tanker endorsement. The hazmat endorsement is about what you are carrying and how to handle it safely; the tanker endorsement is about the vehicle itself.

When you need both endorsements

If you drive a tank truck carrying hazardous materials — gasoline, diesel, propane, liquid chemicals, or any regulated substance — you must have both endorsements. This is the most common scenario for tanker drivers in the fuel and chemical industries. You will take two separate written tests: one for tanker knowledge and one for hazmat knowledge. Some states allow you to take both tests on the same day, but they are scored separately and you must pass both to get both endorsements on your license.

Both endorsements appear on your Commercial Driver's License as separate codes. Your license will show "Tank" and "H" (or the equivalent in your state). If you have only tanker and not hazmat, you cannot legally haul hazardous cargo in that tank truck. If you have hazmat but not tanker, you cannot legally drive a tank truck at all, even if it is empty.

What each test covers

The tanker test includes questions about tank vehicle stability, surge and slosh (how liquid moves inside the tank), weight distribution, safe braking and acceleration, emergency procedures, and inspection of tank vehicles. You learn why tank trucks are more prone to rollover than other trucks, how to adjust your driving for a partially filled tank, and what to do if the tank ruptures. The test is typically 20 questions on most state CDL exams.

The hazmat test covers material classification (nine classes of hazardous materials), shipping papers and documentation, placarding and labeling, loading and unloading procedures, vehicle placarding, accident procedures, and regulations specific to hazmat transport. You learn what materials fall into each hazard class, how to read a shipping paper, what placards go on a vehicle carrying certain materials, and what to do if cargo spills or catches fire. The hazmat test is typically 30 questions.

How to get both endorsements

If you already have a Commercial Driver's License and want to add tanker and hazmat endorsements, you do not need to retake the general CDL written test. You only take the tanker test and the hazmat test. Study materials for both are available from your state's Department of Motor Vehicles or through CDL training programs.

If you are getting your CDL for the first time and know you will need both endorsements, you can take all three tests (general CDL, tanker, and hazmat) during your initial licensing process. Many CDL schools include tanker and hazmat training in their curriculum if you tell them you need those endorsements. After you pass the written tests, you still need to pass the road test in a vehicle appropriate to the endorsements you are seeking — typically a tank truck if you are testing for tanker.

Frequently Asked Questions

Can I get hazmat without tanker?

Yes. You can have hazmat endorsement and haul hazardous materials in a box truck, flatbed, or dry van without ever driving a tank truck. Tanker and hazmat are independent endorsements. You need tanker only if you drive a tank truck; you need hazmat only if you haul hazardous cargo.

Can I get tanker without hazmat?

Yes. You can drive a tank truck carrying non-hazardous materials like water, milk, or food oil with only the tanker endorsement. Many tanker drivers never need hazmat if their company hauls only non-regulated cargo. But if your job ever requires hazmat cargo, you must add that endorsement.

Do I have to take the road test twice if I need both endorsements?

No. You take one road test in a vehicle that meets the requirements for both endorsements — a tank truck. That single road test satisfies the vehicle-operation requirement for both tanker and hazmat endorsements. You still take two separate written tests.

What happens if I drive a tank truck without the tanker endorsement?

It is illegal and you can face fines, license suspension, and criminal charges depending on your state. Operating a tank truck without the proper endorsement is a violation of federal and state commercial driver regulations. Your employer is also liable.

Do I need hazmat if I haul an empty tank truck?

No. An empty tank truck requires only the tanker endorsement. However, if the tank previously held hazardous material and still has residue, regulations may require hazmat endorsement. Check with your employer and your state's regulations about residue requirements.