The National Marker Company placard sign with the legend ?NON-FLAMMABLE GAS? is often used on transport vehicles to inform the drivers on the road that non-flammable gas is being transported. Such signs help enforce safety regulations for transporting hazardous materials. The hazardous material sign shows the message in contrasting colors to ensure clear visibility in most lighting conditions and even from a distance. The material used in the placard signage is waterproof, chemical resistant, and graffiti proof.