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 Massachusetts alone, from the Massachusetts Commercial Driver's License Manual (Preface: Massachusetts CDL Information).
Passing the hazmat knowledge exam yields a pass certificate valid two years while the TSA background check, which takes about 30 days, is completed. Massachusetts does not transfer H endorsements from other states.
About 90 days before expiration, apply through the TSA vendor and get fingerprinted. Results take about 30 days; then take the hazmat knowledge exam and renew with the endorsement.
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.