CDL Class B Endorsements: Types, Tests, and Hazmat TSA Check

A Class B commercial driver’s license can carry five endorsements: Passenger (P), School Bus (S), Tank Vehicle (N), Hazardous Materials (H), and the combined Tank/Hazmat (X). Each Class B CDL endorsement is a separate add-on with its own knowledge test, and three of the five require federally mandated training before you can test. The hazmat endorsement adds a TSA security threat assessment on top of everything else, which is why drivers who need it should start that process well before they need to be on the road.

One endorsement you cannot add to a Class B is the Double/Triple Trailer (T). That one is reserved for Class A licenses.

The Five Endorsements and What They Cover

Federal rules define each endorsement by the type of vehicle or cargo it authorizes, and each shows up on your license as a single-letter code.1eCFR. 49 CFR 383.93 – Endorsements

  • Passenger (P) covers any vehicle designed to carry 16 or more people, including the driver. Transit buses, shuttle buses, and motorcoaches all fall here.
  • School Bus (S) covers vehicles used to transport students from home to school, from school to home, or to and from school events. It is separate from the P endorsement, and most states require you to hold both to drive a school bus.2eCFR. 49 CFR 383.5 – Definitions
  • Tank Vehicle (N) is required when your vehicle carries liquid or gaseous materials in a tank with an individual rated capacity of more than 119 gallons and a total aggregate capacity of 1,000 gallons or more. Both thresholds must be met. A single small tank under 119 gallons on a flatbed does not trigger the requirement.2eCFR. 49 CFR 383.5 – Definitions
  • Hazardous Materials (H) is required whenever you transport hazardous materials in quantities that require placarding. It is the only endorsement that involves a federal security threat assessment run by the TSA.3Transportation Security Administration. HAZMAT Endorsement
  • Tank/Hazmat Combination (X) combines the N and H endorsements. Fuel tanker drivers are the most common example.

What Each Endorsement Test Looks Like

The testing format varies by endorsement. Some are knowledge test only, and two add a behind-the-wheel skills exam.1eCFR. 49 CFR 383.93 – Endorsements

  • Tank Vehicle (N): knowledge test only.
  • Hazardous Materials (H): knowledge test only.
  • Passenger (P): knowledge test plus a skills test in a representative passenger vehicle.
  • School Bus (S): knowledge test plus a skills test in an actual school bus.
  • Combination (X): knowledge tests for both the N and H endorsements.

The skills tests for P and S endorsements must be conducted in a vehicle that matches the class and type you intend to drive. You cannot take the school bus skills test in a transit bus, and vice versa.4eCFR. 49 CFR 383.113 – Required Skills The skills exam covers a pre-trip inspection, basic vehicle control maneuvers, and an on-road driving portion. The federal passing threshold on all written knowledge tests is 80 percent.5Federal Motor Carrier Safety Administration. States Question counts vary by state, but most endorsement exams run between 20 and 30 questions.

Study material lives in your state’s CDL handbook, which lays out the specific knowledge areas for each endorsement. The federal regulations set the required knowledge topics.6eCFR. 49 CFR 383.111 – Required Knowledge The tanker test focuses heavily on liquid surge, rollover risks, and proper loading procedures. The hazmat test covers placarding, shipping papers, and emergency response.

Training You Have to Finish Before You Test

Federal rules require you to complete Entry-Level Driver Training through an FMCSA-registered provider before you can sit for three of the five endorsement exams. First-time applicants for the Passenger (P), School Bus (S), or Hazardous Materials (H) endorsement must finish the relevant ELDT curriculum before their state will let them test.7Federal Motor Carrier Safety Administration. Entry-Level Driver Training (ELDT) This applies even if you have held a CDL for years. What matters is whether you have held that specific endorsement before.

Your training provider must be listed in the FMCSA Training Provider Registry, and the provider reports your completion directly to the registry. Your state licensing agency checks that database before allowing you to schedule the endorsement test.8FMCSA Training Provider Registry. ELDT Applicability

The Tank Vehicle (N) endorsement does not require ELDT. You can go straight to the knowledge test. Budget training time before scheduling a test date, especially for H, where TSA processing adds more lead time on top of the training.

The TSA Threat Assessment for Hazmat

The Hazmat (H) endorsement has the most involved application process because it requires a security threat assessment conducted by the TSA, separate from your state’s licensing procedures. You pre-enroll through the TSA enrollment website, schedule an appointment at an enrollment center, then show up in person with identity documents and get fingerprinted.3Transportation Security Administration. HAZMAT Endorsement

Acceptable identity documents include a current U.S. passport, or a combination of your driver’s license and birth certificate. At the appointment, you pay a non-refundable fee of $85.25 for the threat assessment, or $41.00 if you already hold a valid TWIC card and your state supports the reduced-rate comparability program.9TSA Enrollment by IDEMIA. HAZMAT Endorsement (HME) Threat Assessment Program Payment can be made by credit card, money order, or certified check.

Residents of Florida, Kentucky, Maryland, New York, Pennsylvania, Texas, Virginia, and Wisconsin apply and get fingerprinted through their local DMV rather than a TSA enrollment center.3Transportation Security Administration. HAZMAT Endorsement

Plan for the timeline. TSA recommends enrolling at least 60 days before you need the endorsement, because processing times can exceed 45 days during periods of high demand.3Transportation Security Administration. HAZMAT Endorsement The state knowledge test is the quick part. You cannot get the endorsement printed on your license until TSA clears you.

Criminal History That Disqualifies You

The TSA background check is where applications go sideways for some drivers. Certain convictions permanently bar you from holding an H endorsement, and others disqualify you for a limited period.10Transportation Security Administration. Disqualifying Offenses and Other Factors

Permanent disqualifiers include convictions for espionage, treason, terrorism-related federal offenses, murder, and improper transportation of hazardous materials. Convictions for crimes involving explosives also fall in this category. There is no time limit or waiting period on these bars.

A second group of offenses disqualifies you on an interim basis. These include firearms offenses, arson, robbery, distribution of controlled substances, kidnapping, extortion, fraud, and immigration violations. The disqualification applies if the conviction occurred within seven years of your application date, or if you were released from incarceration within five years of applying.10Transportation Security Administration. Disqualifying Offenses and Other Factors Once both windows have passed, you become eligible again.

If TSA issues a preliminary denial, you have 60 days to respond. Drivers with interim disqualifying offenses who have passed both the seven-year and five-year thresholds can file an appeal. Those who have not passed those thresholds, or who have permanent disqualifiers, can request a waiver, though the bar for waivers is high. Outstanding warrants or pending indictments for any listed offense will also result in disqualification until the matter is resolved.

Adding an Endorsement at Your State Agency

Once you have completed any required ELDT training and, for the H endorsement, received TSA clearance, the remaining steps happen at your state’s licensing agency.

  • Gather your documents: your current CDL, a valid Medical Examiner’s Certificate if required for your self-certification category, proof of identity such as a birth certificate or passport, and your Social Security card. For the H endorsement, bring proof of TSA clearance.
  • Pay the fees. State administrative fees to add an endorsement vary widely. Some states charge as little as $5, others closer to $100. The TSA threat assessment fee of $85.25 is separate and paid directly to TSA. Skills tests for P or S add a testing fee.3Transportation Security Administration. HAZMAT Endorsement
  • Pass the tests. You need at least 80 percent on the written knowledge exam. P and S also require a skills test in a representative vehicle.5Federal Motor Carrier Safety Administration. States
  • Wait for your updated license. The agency updates your record in the Commercial Driver’s License Information System (CDLIS). Most states issue a temporary paper permit on the spot while your new plastic card is printed and mailed, which generally takes two to four weeks.

Fees for endorsement tests and license updates are typically non-refundable, so study before scheduling.

Medical Certification and Keeping Endorsements Current

Every CDL holder must self-certify to their state agency in one of four categories: interstate non-excepted, interstate excepted, intrastate non-excepted, or intrastate excepted.11Federal Motor Carrier Safety Administration. Medical Drivers in a non-excepted category (which covers the vast majority) must maintain a valid Medical Examiner’s Certificate and submit each new one to the state before the current one expires.

Letting your medical certificate lapse is one of the fastest ways to lose your endorsements without doing anything wrong on the road. If your state does not have a current certificate on file, federal rules require them to downgrade your CDL, which strips your authority to operate any commercial vehicle that requires a CDL, endorsements and all.11Federal Motor Carrier Safety Administration. Medical Reinstatement typically means resubmitting a valid certificate and paying any applicable fees. Set a reminder well before the expiration date.

Most endorsements renew automatically when you renew your CDL, and most states do not require you to retake the knowledge test at renewal. Hazmat is the exception. Your TSA security threat assessment is valid for five years, and you must complete a new one before it expires to keep the H or X endorsement on your license.3Transportation Security Administration. HAZMAT Endorsement Most states also require you to retake the hazmat knowledge test at renewal.

If you let TSA clearance lapse, your state will remove the H endorsement from your license. Getting it back means going through the full enrollment process again: fingerprinting, fee, background check, and the waiting period that comes with it. Because that process can run 60 days or more, track the five-year expiration date the same way you track your medical certificate, and start the renewal at least 90 days before it runs out.

Federal regulations also allow states to suspend or revoke commercial driving privileges for drivers found operating outside their self-certified medical category.11Federal Motor Carrier Safety Administration. Medical Serious traffic violations or certain criminal convictions can also cost you an endorsement after you have been cleared once.