H endorsement: placarding, shipping papers and the segregation table.
Most Hazardous Materials questions are the same federal material in every state. 2 questions in the app are written for Missouri alone, from the Missouri Commercial Driver License Manual (Version 4.0, Revised August 2025).
Missouri requires the hazmat written test at a Highway Patrol testing office every time you renew or add endorsements, plus fingerprints and a security threat assessment. A hazmat licence is never issued beyond the current threat assessment date.
The hazmat endorsement exam has 30 questions, more than any endorsement exam except general knowledge. A score of 80 percent is required.
One example, answer shown. Practicing the rest happens in the app.
Table 2 materials need placards once the aggregate gross weight, including packaging, reaches 1,001 pounds. Table 1 materials must be placarded in any amount.