What a 4/5 endorsement means and why you need it
A 4/5 endorsement on your Ohio CDL is the hazardous materials (hazmat) endorsement. The "4" and "5" are Ohio's internal codes for this single endorsement — you'll see it written as either one. If your job involves transporting hazardous materials like fuel, chemicals, explosives, or radioactive substances, Ohio law requires you to have this endorsement on your CDL before you drive.
Without it, you cannot legally haul hazmat loads, even if you have a valid CDL. Your employer cannot assign you to those routes, and you cannot accept payment for that work. The endorsement proves you've passed a knowledge test specific to hazmat regulations and that you've passed a federal background check.
Ohio does allow you to test for the 4/5 endorsement online through a third-party testing vendor, which means you don't have to visit an Ohio Bureau of Motor Vehicles (BMV) office in person for the written exam — though you will need to visit one to add the endorsement to your license after you pass.
Key Takeaways
- The 4/5 endorsement is Ohio's hazmat endorsement, required to transport hazardous materials on a CDL.
- You can take the written knowledge test online through an approved third-party vendor, but you must visit a BMV office in person to have the endorsement added to your physical license.
- You must pass a federal Transportation Security Administration (TSA) background check before the endorsement can be issued.
- The knowledge test covers hazmat regulations, shipping papers, placarding, and emergency procedures specific to the materials you'll transport.
- Ohio charges a fee for the endorsement, and the TSA background check has its own separate cost.
Steps to get your 4/5 endorsement through online testing
Start by scheduling your hazmat knowledge test with an Ohio-approved third-party testing vendor. The BMV website lists the vendors currently authorized to administer CDL tests online. You'll create an account with the vendor, select a test date and time that works for you, and pay their testing fee (this varies by vendor but typically ranges from $10 to $30).
On test day, you'll take the exam from a location with a reliable internet connection — your home, a library, or a testing center. The vendor will monitor you via webcam to prevent cheating. The test covers hazmat-specific rules: how to classify hazardous materials, what shipping papers must accompany them, how to mark and placard vehicles, and what to do in an emergency like a spill or leak.
Once you pass, the vendor sends your passing score to the Ohio BMV. You then schedule an appointment at your local BMV office to complete the in-person portion. Bring your current CDL, proof of your passing test score, and be prepared to pay the Ohio endorsement fee (currently $20 for a 4-year endorsement, though fees can change). The BMV will issue you a new CDL with the 4/5 endorsement printed on it.
The TSA background check requirement
Before Ohio can issue your 4/5 endorsement, you must pass a federal Transportation Security Administration (TSA) background check. This is a separate process from the knowledge test and happens after you pass the written exam.
The TSA will review your criminal history, immigration status, and other factors to determine whether you pose a security risk. The check typically takes one to two weeks, though it can take longer if the TSA needs additional information from you. If you have certain felonies, outstanding warrants, or immigration issues, you may be disqualified.
You don't pay the TSA directly — the fee is usually included in what you pay the BMV when you add the endorsement to your license. However, if the TSA denies you, you can request a waiver or appeal, which involves additional paperwork and waiting time.
What to study for the hazmat knowledge test
Ohio's hazmat test has 30 questions, and you must answer at least 24 correctly (80%) to pass. The test covers nine main topics: hazard classes and divisions, shipping papers and documentation, marking and labeling, placarding, loading and unloading, vehicle operation, hazmat incidents and emergencies, and regulations specific to certain materials like explosives or radioactive goods.
The Ohio BMV publishes a free hazmat study guide on its website. You can also purchase third-party study materials, take practice tests online, or use flashcard apps. Many drivers study for two to four weeks before testing, depending on their background with hazmat regulations.
The test is not timed, so you can take as long as you need to answer each question. However, you only get one attempt per test appointment — if you fail, you must schedule and pay for another test.
Timeline and costs
The entire process typically takes three to six weeks from start to finish, though it can be faster or slower depending on how quickly you schedule your test and how long the TSA background check takes.
| Step | Typical Timeline | Cost |
|---|---|---|
| Schedule and take online knowledge test | 1 to 2 weeks | $10–$30 (vendor fee) |
| TSA background check | 1 to 2 weeks | Included in BMV fee |
| Visit BMV office to add endorsement | Same day or next available appointment | $20 (Ohio endorsement fee) |
| Receive new CDL in mail | 5 to 10 business days | No additional cost |
Total cost is usually $30 to $50, depending on the vendor's testing fee. Some employers reimburse this cost; check with your company before you pay out of pocket.
What happens if you fail the test or the background check
If you fail the knowledge test, you can retake it as many times as you need. You'll pay the vendor's fee again for each attempt. Most people pass on the second or third try if they study the material between attempts.
If the TSA background check disqualifies you, you have the right to request a waiver or appeal the decision. The TSA will tell you the reason for the denial and explain how to request a waiver. This process can take several months and may require you to provide additional documentation or attend a hearing. Not all denials can be overturned, so speak with a lawyer if you're unsure whether you have grounds to appeal.
Renewing or removing your 4/5 endorsement
Your 4/5 endorsement is valid for four years and renews with your CDL. When your CDL expires, you can renew the endorsement at the same time by visiting a BMV office. You'll need to pass the hazmat knowledge test again and pass another TSA background check.
If you no longer need the endorsement — for example, if you change jobs and no longer transport hazmat — you can ask the BMV to remove it from your license. This is free and can be done at any BMV office.
Frequently Asked Questions
Can I take the hazmat test online if I'm renewing my CDL?
Yes. Whether you're adding the endorsement for the first time or renewing it, you can take the knowledge test online through an approved vendor. You'll still need to visit a BMV office in person to have the endorsement added or renewed on your physical license.
What disqualifies you from getting a hazmat endorsement?
The TSA background check can disqualify you for certain felonies (especially those involving explosives, weapons, or terrorism), outstanding warrants, or immigration violations. Specific disqualifying offenses are listed on the TSA website. You can request a waiver if you believe your case warrants an exception.
Do I need a hazmat endorsement if I only transport certain materials?
Yes. If your job involves transporting any quantity of hazardous materials that require placarding under federal law, you need the 4/5 endorsement. There are no exceptions based on the type or amount of hazmat. Check with your employer or the U.S. Department of Transportation if you're unsure whether your cargo requires hazmat placarding.
How long does the TSA background check take?
Typically one to two weeks, but it can take longer if the TSA requests additional information from you or needs to investigate something in your background. You'll be notified by email or mail if the TSA needs more details from you.
Can I drive hazmat loads while I'm waiting for my endorsement to be added to my license?
No. You cannot legally transport hazmat until the 4/5 endorsement is printed on your physical CDL. Even if you've passed the test and the background check, you must wait until you visit the BMV office and receive your new license in the mail.