What you need to do to add hazmat and tanker to your Class C license
To add a hazmat endorsement and a tanker endorsement to your Class C commercial driver's license, you must pass two separate written tests through your state's Department of Motor Vehicles (DMV) and pass a hazmat background check. The hazmat endorsement allows you to transport hazardous materials; the tanker endorsement allows you to transport liquids or gases in bulk tanks. You cannot get either endorsement without first holding a valid Class C CDL.
The process takes roughly four to eight weeks from start to finish, depending on how quickly your background check clears and when your state's DMV can schedule your tests. You will need to study for two different written exams, pass a Transportation Security Administration (TSA) background check for hazmat, and pay separate fees to your state DMV for each endorsement.
Key Takeaways
- You must already hold a valid Class C CDL before you can add hazmat or tanker endorsements.
- Both endorsements require passing separate written tests at your state DMV, plus a TSA background check for hazmat only.
- Study materials for both tests are available free from your state DMV website, and many states offer practice tests online.
- The hazmat background check typically takes two to four weeks; tanker endorsement has no separate background requirement.
- Each endorsement costs a separate fee that varies by state, usually between $15 and $85 per endorsement.
Get your hazmat background check started first
The hazmat endorsement requires a TSA background check, which is the longest part of the process. You cannot take the hazmat written test until your background check is submitted and you have received a notice of clearance or conditional clearance from TSA. Start this step before you study for either test, because the background check runs in parallel with your test preparation.
Contact your state DMV and ask for the hazmat background check form (often called the HME form or hazmat endorsement process). Fill it out completely with your legal name, date of birth, Social Security number, and current address. You will need to list any previous addresses from the past five years. Submit the form to your state DMV along with the required fee, which varies by state but is typically $15 to $25.
Your state DMV will forward your process to TSA. TSA will send you a letter within two to four weeks confirming whether you have been cleared, conditionally cleared, or denied. Keep this letter — you will need to show it when you take your hazmat test. If you are denied, you can request a hearing, but you cannot take the hazmat test until the denial is overturned.
Study for the hazmat written test
The hazmat test covers the hazardous materials regulations in the Federal Motor Carrier Safety Regulations (FMCSR). You will be tested on how to identify hazardous materials, how to load and find them, what placards and labels mean, what to do in an emergency, and your responsibilities as a hazmat driver. The test is typically 30 questions, and you must score at least 80 percent to pass.
Your state DMV publishes a free hazmat study guide on its website. read it and read through it completely — this is the official source material for the test. Many states also offer free online practice tests through their DMV website. Take the practice test multiple times until you consistently score above 85 percent, then schedule your test appointment.
The hazmat manual covers topics like the hazmat table (which lists what materials are regulated), shipping papers, placarding rules, and emergency procedures. Pay close attention to the sections on loading and unloading, because those questions appear frequently on the actual test. If your state offers in-person study sessions at DMV offices, attend one — instructors often highlight the most commonly tested material.
Study for the tanker written test
The tanker test covers the specific rules for transporting liquids and gases in bulk tanks. You will be tested on tank construction and inspection, how to load and unload different types of cargo, how to handle surge and slosh (the movement of liquid inside the tank), braking and handling differences for tanker vehicles, and emergency procedures. The test is typically 20 questions, and you must score at least 80 percent to pass.
Your state DMV publishes a free tanker study guide separate from the hazmat guide. The tanker manual is shorter than the hazmat manual but more technical — it focuses on the physics of how liquids move in tanks and how that affects your driving. Read the entire manual, then take the practice test repeatedly until you score above 85 percent consistently.
Tanker-specific topics that appear frequently on tests include surge (the forward and backward movement of liquid when you brake or accelerate) and slosh (the side-to-side movement when you turn). Understand why these movements happen and how they affect your ability to control the vehicle. Also study the differences between baffled tanks (which have internal dividers) and unbaffled tanks (which do not), because the handling characteristics are very different.
Schedule and take both written tests
Once you have your TSA clearance letter for hazmat and you feel ready for both tests, contact your state DMV to schedule your test appointments. Many states allow you to take both tests on the same day; some require you to take them on different days. Ask when you call. You will need to bring your valid Class C CDL, your TSA clearance letter (for hazmat), and a government-issued photo ID.
Arrive at least 15 minutes early. The DMV will verify your identity and your TSA clearance, then seat you at a computer terminal to take the test. You will have a set amount of time (usually 30 to 60 minutes per test) to complete it. The test is multiple choice, and you will see your score when ready after you finish.
If you pass both tests, the DMV will print your new Class C CDL with both endorsements on the spot or mail it to you within one to two weeks, depending on your state. If you fail either test, you can retake it after a waiting period (usually 24 hours to one week, depending on your state). There is typically a retake fee of $5 to $15 per test.
Pay the endorsement fees
Each endorsement carries a separate fee charged by your state DMV. Hazmat endorsement fees range from $15 to $85 depending on your state; tanker endorsement fees range from $10 to $50. Some states charge the fee when you submit your hazmat background check process; others charge it when you take the test; still others charge it when you pick up your new license. Ask your DMV which fees explore and when they are due.
Most states accept payment by check, money order, or credit card. Some DMV offices accept cash. If you are taking your tests in person, bring payment in the form your local DMV accepts. If you are submitting applications by mail, include a check or money order with your process.
What happens after you pass
Once you pass both tests, your state DMV will issue a new Class C CDL with the hazmat and tanker endorsements printed on it. The endorsement will appear as "H" for hazmat and "N" for tanker on the front of your license. Your new license will have an expiration date — most states expire CDLs every four to eight years, depending on your age and whether you have a hazmat endorsement.
Hazmat endorsements typically expire every five years and require a new background check to renew. Tanker endorsements usually expire with your CDL and do not require a separate renewal process. When your hazmat endorsement is about to expire, your state DMV will send you a notice. You will need to submit a new background check process and fee to renew it.
Frequently Asked Questions
Can I take the hazmat test before my background check clears?
No. You must have your TSA clearance letter in hand before you can take the hazmat test. However, you can take the tanker test while your hazmat background check is pending. Many drivers take the tanker test first, then take the hazmat test once their clearance arrives.
What if I fail the hazmat background check?
If TSA denies your background check, you will receive a letter explaining the reason. You have the right to request a hearing to challenge the denial. Contact TSA's Hazmat Security Division to request a hearing. You cannot take the hazmat test until the denial is overturned, but you can still obtain the tanker endorsement.
Do I need to renew both endorsements at the same time?
No. Tanker endorsements renew with your CDL, but hazmat endorsements renew separately every five years. When your hazmat endorsement is about to expire, submit a new background check process and fee to your state DMV. You do not need to retake the hazmat test to renew it, only to pass the background check again.
Can I get both endorsements if I have a criminal record?
It depends on the offense. TSA will deny a hazmat endorsement if you have certain felony convictions, disqualifying offenses, or security-related issues. Tanker endorsement has no separate background check, so a criminal record does not automatically disqualify you. If you are unsure whether your record will affect your hazmat clearance, contact your state DMV or TSA before you explore.
How long does the whole process take?
From the day you submit your hazmat background check to the day you receive your new license with both endorsements, expect four to eight weeks. The hazmat background check typically takes two to four weeks. Test scheduling and processing adds another one to two weeks. If you fail either test and need to retake it, add another week or two.