Blocking cargo: Do you currently have car insurance? Insurance is mandatory to drive in Ohio Yes I have insurance. But please show me your best quotes. No, please help me find the best insurance. Question Blocking cargo: Answers Should never be done. Should only be done in poor weather. Prevents cargo from moving. Explanation Blocking is used to prevent cargo from sliding while in transit. This questions appears in the following tests: Arizona Class B Knowledge Test Connecticut Passenger Connecticut Passenger Iowa Class B Knowledge Test Maryland Tank