On the Iowa driving test, cdl hazmat questions are part of the 35-question exam. Iowa requires a score of 80% (28 correct answers) to pass.
The Hazardous Materials (HazMat) endorsement is required for drivers who transport hazardous materials in quantities that require placarding. This includes flammable liquids, explosives, corrosives, poisons, and radioactive materials.
HazMat drivers must understand the nine hazard classes, how to read shipping papers and material safety data sheets, and the proper placarding requirements for their load. Placards must be placed on all four sides of the vehicle and must be visible from each direction.
Routing restrictions, parking rules, and emergency response procedures are also critical. HazMat drivers cannot park within 300 feet of an open fire and must carry specific emergency equipment. In an accident involving hazardous materials, the driver’s first responsibility is to protect the public by establishing a safety zone.