Class 1.1 explosives must not be transported in a combination vehicle if it includes:

• A. A placarded cargo tank
• B. A non-placarded cargo tank
• C. A plastic crate
• D. A wood box

Answer: (A)

Class 1.1 explosives are mass-explosion hazards and must be kept separate from other hazardous loads on a single vehicle. The placard on a cargo tank signals that large quantities of hazardous materials are being carried, which creates a much higher risk if kept on the same vehicle as explosives. When a combination vehicle includes a placarded cargo tank, transporting Class 1.1 explosives together with that tank is prohibited because a mass detonation could affect the entire vehicle and beyond. If the tank isn’t placarded, the specific restriction tied to the placard doesn’t apply in the same way. Packaging type alone isn’t the deciding factor—the placard on a cargo tank is what triggers this safety rule.