Practice question What does Hazard Class 6 include? Poisonous/toxic and infectious substancesOnly the carrier invoice numberOnly the driver personal preferenceA rule that applies only to passenger cars Answer: A — Poisonous/toxic and infectious substances The correct answer is shown above. Try the full quiz for additional practice. Practice more: Alabama CDL HazMat Practice Questions - Alabama CDL Hazardous Materials Endorsement Test Exam →