The 45 Endorsement Lets You Haul Hazardous Materials

The 45 endorsement on a Commercial Driver's License (CDL) authorizes you to transport hazardous materials — substances the Department of Transportation classifies as dangerous because they can harm people, property, or the environment. Without this endorsement, you cannot legally haul these materials for pay, even if you hold a valid CDL in the appropriate class.

The "4" and "5" are separate endorsements that work together. The 4 endorsement covers hazardous materials in general. The 5 endorsement covers tank vehicles — tankers that carry liquids or gases. Most drivers who need to haul hazmat also need the 5 endorsement because many hazardous materials travel in tank trucks. Some states and employers may require both; others may allow you to hold just the 4 if you are not driving a tanker.

Getting a 45 endorsement requires passing a written test specific to hazmat regulations, obtaining a Transportation Security Administration (TSA) background check and security clearance, and meeting medical requirements. The process typically takes several weeks because the TSA clearance involves fingerprinting and a federal records review.

Key Takeaways

  • The 4 endorsement covers hazardous materials transport; the 5 endorsement covers tank vehicles; most drivers need both together as a 45 endorsement.
  • You must pass a written hazmat knowledge test, pass a TSA security clearance, and meet medical standards before you can receive the endorsement.
  • The TSA background check is the longest part of the process and can take four to six weeks or longer depending on the agency's workload.
  • Your employer may require the 45 endorsement as a condition of hire, or you may pursue it to expand the types of loads you can legally transport.

What Hazardous Materials Means in CDL Terms

Hazardous materials include explosives, flammable liquids and gases, oxidizers, poisons, radioactive materials, corrosives, and other substances that the Department of Transportation has designated as dangerous in transport. Common examples are gasoline, diesel fuel, propane, chlorine, pesticides, and certain pharmaceuticals.

The hazmat rules explore whether you are hauling a full load or a partial load. If your cargo includes any amount of a regulated hazardous material, you must have the 45 endorsement and follow all hazmat placarding, documentation, and safety rules. This is why the endorsement is required even for drivers who may only occasionally transport these materials.

The Written Test for Hazmat Knowledge

Before you can take the hazmat test, your state's Department of Motor Vehicles will require you to pass a background check — separate from the TSA clearance. This state-level check screens for disqualifying criminal convictions and certain traffic violations. Once you clear that, you can schedule the written test.

The hazmat test covers regulations in the Code of Federal Regulations (CFR) Title 49, which governs the transportation of hazardous materials. The test typically includes 30 to 50 multiple-choice questions covering topics such as hazard classes, proper labeling and placarding, documentation requirements, vehicle safety equipment, emergency procedures, and driver responsibilities. You must usually score 80 percent or higher to pass.

Study materials are available through your state's DMV website and through the Federal Motor Carrier Safety Administration (FMCSA). Many CDL training schools also include hazmat preparation in their curriculum. The test is offered at the same location where you take your other CDL written tests.

The TSA Security Clearance Process

After you pass the written test, you must obtain a Transportation Security Administration (TSA) hazmat endorsement security clearance. This is a federal background investigation, not a state process. The TSA reviews your criminal history, immigration status, and other records to determine whether you pose a security risk.

To begin the TSA clearance, you will submit fingerprints and personal information through an approved channeler — a private company authorized by the TSA to collect biometric data. Your state's DMV will direct you to an approved channeler in your area. You pay a fee (typically $85 to $100) to the channeler for fingerprinting and submission. The channeler sends your fingerprints to the FBI and TSA for review.

The TSA then conducts a records check that can take four to six weeks or longer. During this time, you cannot legally drive with a hazmat load, even if you have passed the written test. Once the TSA approves your clearance, your state's DMV will add the 45 endorsement to your CDL. If the TSA denies your clearance, you will receive a written explanation and may have the right to appeal.

Medical Requirements and Other Prerequisites

You must meet the same medical standards required for any CDL. This means passing a Department of Transportation (DOT) physical examination performed by a certified medical examiner. The exam checks your vision, hearing, blood pressure, and overall fitness to operate a commercial vehicle safely. If you already hold a valid CDL with a current medical certificate, you have already met this requirement.

You must also hold a valid CDL in the appropriate class for the vehicle you will be driving. For example, if you are hauling hazmat in a tractor-trailer, you need a Class A CDL. If you are driving a smaller hazmat vehicle, you may need a Class B or C. The 45 endorsement is added to whichever class you already hold.

Timeline and Cost

The entire process from written test to endorsement typically takes four to eight weeks, depending mainly on how long the TSA clearance takes. The written test itself can usually be scheduled within days of your request. The TSA clearance is the variable — federal processing times fluctuate based on workload and complexity of individual cases.

Costs vary by state but generally include a written test fee (usually $10 to $30), a channeler fingerprinting fee ($85 to $100), and a state endorsement fee ($5 to $50). Some employers cover these costs for employees; others require the driver to pay. Check with your employer or your state's DMV for the exact fees in your area.

Renewing Your 45 Endorsement

The 45 endorsement is valid for the same period as your CDL — typically four or eight years depending on your state and age. When your CDL expires, you must renew the endorsement at the same time. Renewal requires passing the hazmat written test again and obtaining a new TSA security clearance.

The TSA clearance renewal process is the same as the initial clearance: fingerprinting through an approved channeler, federal background review, and a waiting period. Some states allow you to renew your CDL and hazmat endorsement at the same time; others require separate transactions. Contact your state's DMV for renewal procedures specific to your location.

Frequently Asked Questions

Can I drive a tanker without the 5 endorsement if I have the 4?

No. The 5 endorsement is required to operate any tank vehicle, regardless of what cargo it carries. If you hold only the 4 endorsement, you cannot legally drive a tanker, even if it is empty or carrying non-hazardous material. Most drivers who haul hazmat in tankers need both endorsements together.

What disqualifies you from getting a TSA hazmat clearance?

The TSA denies clearance for certain criminal convictions (felonies and some misdemeanors), immigration violations, and security-related offenses. Specific disqualifying crimes include felony drug convictions, violent felonies, and crimes involving explosives or weapons. You will receive written notice if your clearance is denied and information about your right to appeal.

Do I need the 45 endorsement if I only haul hazmat occasionally?

Yes. If you transport any amount of a regulated hazardous material for pay, you must hold the 45 endorsement. There is no exception for occasional or part-time hazmat hauling. Your employer determines whether hazmat transport is part of your job; if it is, the endorsement is required.

What happens if my TSA clearance is denied?

You will receive a written notice explaining the reason for denial. You have the right to request reconsideration or appeal through the TSA's administrative process. The notice will include instructions for filing an appeal. If your appeal is denied, you cannot obtain the 45 endorsement unless the disqualifying issue is resolved.

Can I renew my 45 endorsement online?

Most states require you to renew your CDL and endorsements in person at a DMV office, though some states offer limited online renewal options for CDL holders with clean records. Contact your state's DMV to learn whether online renewal is available for your situation. Even if CDL renewal is online, you will likely need to visit a DMV office for fingerprinting for the TSA clearance renewal.