The hazmat endorsement test has 30 questions, and you need to answer at least 24 correctly to pass

The hazmat endorsement test administered by your state's Department of Motor Vehicles contains exactly 30 multiple-choice questions. To pass, you must score at least 80 percent, which means getting 24 or more questions right. The test covers hazardous materials regulations, safety procedures, and how to handle different classes of dangerous goods.

This is a written test only — there is no practical driving component for the hazmat endorsement itself. You take it at your local DMV office or testing center, either on a computer or on paper depending on what your state offers. The test is separate from your regular commercial driver's license (CDL) written exam, though you must already have a valid CDL to take the hazmat test.

Key Takeaways

  • The hazmat endorsement test contains 30 multiple-choice questions, and you must answer at least 24 correctly to pass.
  • All 30 questions come from the hazmat section of the CDL manual your state provides, so studying that manual is the main way to prepare.
  • You have a set amount of time to complete the test — usually 60 minutes — though the exact time limit varies by state.
  • You must pass a background check and pay a fee before you can take the test, and the endorsement itself expires every five years.

What topics the 30 questions cover

The questions test your knowledge of nine classes of hazardous materials: explosives, gases, flammable liquids, flammable solids, oxidizers, poisons, radioactive materials, corrosives, and miscellaneous hazardous materials. You will also see questions about loading and unloading procedures, placarding requirements, and how to respond to spills or accidents.

The test also covers rules about which hazardous materials you can and cannot transport together, what paperwork you need to carry, and how to communicate hazards to other drivers and emergency responders. Questions about vehicle safety — brakes, tires, lights, and cargo securement — appear as well, since transporting hazmat requires equipment in top condition.

Every question pulls directly from the hazmat section of your state's CDL manual. There are no trick questions or material outside that manual, so if you study the manual thoroughly, you will have seen the content before you sit for the test.

How much time you have to take the test

Most states give you 60 minutes to answer all 30 questions. That works out to two minutes per question on average, which is enough time to read carefully and think through your answer. Some states may allow slightly more or less time, so check with your local DMV office about the exact time limit in your state.

You do not need to rush. The test is not timed in a way that catches people off guard — most people who have studied the material finish with time to spare. If you find yourself stuck on a question, you can mark it and come back to it before you submit your answers.

How the test is scored and what happens if you fail

Your score is calculated when ready after you finish. If you pass, you walk out with your hazmat endorsement added to your CDL that same day, or within a few days if you took a paper test. If you do not pass, you can retake the test, but you will need to pay the fee again and may have to wait a certain number of days before your next attempt — this waiting period varies by state.

There is no penalty for failing other than the cost of retaking the test and the time it takes. You can take the test as many times as you need to pass. Many people pass on their second or third attempt after spending more time with the manual.

Requirements before you can take the test

You must have a valid CDL in your state before you can take the hazmat endorsement test. You also have to pass a Transportation Security Administration (TSA) background check, which includes fingerprinting and a records review. This background check is separate from the written test and can take several weeks to complete.

You will pay a fee to take the test — the amount varies by state, typically between $10 and $100. You also pay a separate fee for the TSA background check, which is usually around $85 to $97. Some states bundle these fees together; others charge them separately. Contact your state DMV to find out the exact costs and what documents you need to bring.

How to prepare for the 30 questions

The best way to prepare is to read the hazmat section of your state's CDL manual from start to finish, then go through it again and take notes on anything you did not understand the first time. Many states offer practice tests online or through their DMV website — these practice tests use real questions from past exams and show you the format you will see on test day.

Study groups and commercial driver training schools also offer hazmat prep courses. These courses are not required, but they can help if you learn better in a classroom setting or with an instructor answering your questions. Some people study on their own with just the manual and pass easily; others benefit from the structure of a course.

Focus on understanding the material, not just memorizing answers. The test questions are straightforward, and if you understand why certain materials are dangerous and what procedures keep drivers and the public safe, you will be able to answer the questions even if they are worded slightly differently than in the manual.

How long the hazmat endorsement lasts

Once you pass the test and receive your hazmat endorsement, it is valid for five years from the date it is issued. After five years, you will need to retake the written test to renew it. You do not need to retake the TSA background check if you already passed one and your endorsement is straightforward expiring — you only need to pass the written test again.

If your CDL expires before your hazmat endorsement does, you will lose the hazmat endorsement when you renew your CDL. You will have to pass the hazmat test again to add it back to your new CDL.

Frequently Asked Questions

Can I use a calculator or notes during the hazmat test?

No. You cannot bring any materials into the testing room except your identification and any documents the DMV requires. The test does not involve math that requires a calculator, and all the information you need is in the questions themselves or in your memory from studying the manual.

What happens if I fail the hazmat test?

You can retake the test after waiting a certain number of days — usually three to seven days, depending on your state. You will need to pay the test fee again. There is no limit to how many times you can retake it, so you can keep trying until you pass.

Do all 30 questions appear on every hazmat test, or does the test change?

The test always has 30 questions, but the specific questions change from test to test. They are drawn from a larger pool of questions that all cover the same topics in the hazmat manual. This is why studying the manual thoroughly is more important than trying to memorize specific questions.

Is the hazmat test harder than the regular CDL written test?

The hazmat test is considered more specialized and detailed than the general CDL test, but it is not necessarily harder if you study the material. The questions are straightforward and directly tied to the hazmat manual. Most people who study the manual carefully pass on their first or second attempt.

Can I take the hazmat test online from home?

Most states require you to take the hazmat test in person at a DMV office or approved testing center. A few states may offer remote testing options, but this is rare. Contact your state DMV to find out whether remote testing is available where you live.