A tractor trailer carrying gasoline should display which color placard?

The appropriate placard for a tractor trailer carrying gasoline is red, specifically representing flammable liquids. This color coding is part of the Hazardous Materials Regulations (HMR) and is designed to provide immediate visual identification of the type of hazard involved. The number three on the placard indicates that the material is a flammable liquid, which is critical information for first responders and anyone nearby.

Gasoline is classified as a flammable liquid, and the use of this specific color and number helps ensure that it is easily recognizable, allowing for safer handling and response in the event of an emergency. Proper identification through placards is essential in preventing accidents and ensuring that all personnel are aware of the potential dangers posed by the cargo.