HAZMAT Endorsement Study Guide

Hauling hazardous materials. Higher pay, more responsibility, plus a TSA background check.

The HAZMAT endorsement (sometimes called the H endorsement) is the most lucrative single endorsement on a CDL, but it also requires the most preparation and the most paperwork. Beyond the written test, you'll need a TSA Threat Assessment background check that takes weeks to clear. Plan accordingly — you can't show up to the DMV and walk out with HAZMAT on your license the same day.

What HAZMAT covers

Hazardous materials are anything the Department of Transportation classifies as posing a risk to health, safety, or property when transported. The DOT defines nine hazard classes: explosives, gases, flammable liquids, flammable solids, oxidizers, toxics, radioactive materials, corrosives, and miscellaneous. Each class has subdivisions and each requires specific handling, placarding, and emergency response procedures.

The test covers placarding rules, shipping papers, loading and unloading procedures, segregation requirements (which classes can't be transported together), parking restrictions, and emergency response. Expect about 30 questions, with 80% required to pass.

The TSA background check

Before you can take the HAZMAT test, you have to apply for the TSA Hazardous Materials Endorsement Threat Assessment. This involves fingerprinting, an FBI criminal records check, and review against terrorist watch lists. The process typically takes 30 to 60 days. Disqualifying convictions include: felonies involving explosives, terrorism, espionage, sedition, treason, transportation security incidents, improper transportation of hazardous materials, murder, attempts to commit any of the above, or RICO violations.

The TSA portion costs around $86.50 (subject to change) and is paid directly to the TSA, separate from any state DMV fees. Apply early — schedule your DMV written test for after the TSA approval is expected to arrive.

Placarding

Placards are the diamond-shaped warning signs you see on trucks and rail cars. They identify the hazard class of what's being transported. The test will quiz you on placarding rules in detail:

• Four placards required. One on each side of the vehicle and one each on the front and rear, all visible and readable.
• Placards required for any amount of certain materials. Class 1.1, 1.2, 1.3 (explosives), Class 2.3 (poison gas), Class 4.3 (dangerous when wet), Class 5.2 (organic peroxides type B), Class 6.1 PG I (inhalation hazard), and Class 7 (radioactive III).
• 1,001-pound rule. Most other hazard classes require placards only if the vehicle carries 1,001 pounds or more (gross weight including packaging).
• Subsidiary placards. Some materials have a primary hazard plus a secondary risk and require two placards.

Shipping papers

Shipping papers describe what's in the truck, in what quantities, and to whom. They must be:

• Within reach of the driver while driving (typically clipped to the visor or in a pocket on the driver's door).
• Clearly identifiable as HAZMAT papers (highlighted, marked with an "X" in the HM column, or printed on yellow paper).
• Placed on the driver's seat or in the door pocket when the driver leaves the cab.
• Available to emergency responders at all times.

The shipping papers and the placards must agree. If the placards say flammable liquid but the papers say corrosive, something is wrong and you should not move the vehicle until the discrepancy is resolved.

Loading and unloading

The driver is responsible for ensuring the load is secure, properly placarded, and compatible with what's already in the truck. Some highlights tested on the exam:

• Engine off during loading and unloading of flammable liquids.
• No smoking within 25 feet of any vehicle containing Class 1 (explosives), Class 3 (flammable liquids), Class 4 (flammable solids), or empty tanks that previously contained these materials.
• Set parking brake before loading or unloading.
• Never load damaged containers. Refuse the shipment.
• For Division 1.1 and 1.2 explosives, the driver must inspect the cargo space before loading. The space must be clean, with no cracks or holes that could trap a spark or expose cargo to a heat source.

Parking and route restrictions

HAZMAT vehicles cannot park within five feet of the traveled portion of a road except for brief stops necessary for vehicle operation. They cannot park within 300 feet of an open fire. Routes through cities and tunnels are often restricted — many tunnels prohibit certain HAZMAT classes entirely. State and local rules vary, so check the route plan before each trip.

Division 1.1 and 1.2 explosives require an attendant at all times when the vehicle is parked, except in specific authorized situations. The attendant must be alert, awake, in or within 100 feet of the vehicle, and must have a clear view of the vehicle.

Emergency response

If something goes wrong — fire, leak, accident — the driver's job is not to be a hero. The job is to:

1. Stop the vehicle in the safest available location.
2. Notify emergency services. Use the Emergency Response Guidebook (ERG) reference number on the shipping papers to give responders the right information.
3. Keep people away. Set out warning devices.
4. Provide shipping papers and information to responders when they arrive.
5. Never use a road flare in the presence of leaking flammable liquid.

The Emergency Response Guidebook is testable content. Know that it's organized by UN/NA identification number and that the front section gives generic response procedures while the indexed sections give material-specific ones.

How to study

HAZMAT has more memorization than any other CDL test. Focus on placarding tables, segregation tables, and emergency procedures. Take our practice test below repeatedly until you're consistently above 90%. The test is dense — read every question carefully.