Hazardous Materials Placard
A standardized warning sign required on vehicles carrying hazardous materials in quantities triggering placarding rules under 49 CFR Part 172.
Placards identify the hazard class of the cargo (flammable, toxic, explosive, corrosive, etc.) and are designed to be readable from a distance by emergency responders. A CDL driver transporting a placarded load requires a HazMat (H) endorsement. The shipper is responsible for providing placards; the carrier is responsible for affixing them correctly.
When placards are required
Placards are required based on hazard class and quantity. For most hazard classes (Table 2 materials), placards are required when the aggregate load exceeds 1,001 lbs. Some extremely hazardous materials (Table 1 materials including certain explosives, poisons, and radioactive materials) require placarding for any amount. The shipper provides the correct placards and shipping papers describing the cargo; the carrier and driver are responsible for affixing placards correctly and verifying they match the shipping documentation.
Placards and the HazMat CDL endorsement
Operating a vehicle that requires hazardous materials placards requires a HazMat (H) endorsement on the driver's CDL. Getting the endorsement requires passing the HazMat knowledge test AND completing a TSA security threat assessment (fingerprint-based background check) — the TSA review adds several weeks to the process. The endorsement must be renewed each time the CDL is renewed and the TSA background check must be repeated. Drivers without the H endorsement should not operate placarded loads, even temporarily.
Last updated: May 28, 2026
When this definition matters
This term usually matters when a driver, owner-operator, or small carrier is deciding whether a federal rule applies, preparing a compliance file, or checking a state CDL step. Use this definition as a starting point, then confirm the controlling requirement in the official source listed below before making a licensing, hiring, dispatch, or recordkeeping decision.
The related terms above are included because they often appear in the same compliance workflow. Reviewing them together can prevent common mix-ups, such as treating a state licensing step as a federal carrier obligation or confusing a driver record with a separate employer record.