DOT has classified hazardous materials according to their primary danger and has assigned standardized symbols to identify the classes.Materials are grouped by their major hazardous characteristics;however, many materials will have other hazards as well. Ethanol andethanol-fuel blends are in the flammable liquids category. Placards for flammable liquids have a red background with a white flame and the word “Flammable” on them (see Figure 3.3).