Final answer:
The Flame symbol in the NFPA 704 hazard diamond specifically represents flammable materials, indicating fire risk and flammability level on a scale from 0 to 4.
Step-by-step explanation:
The symbol of Flame (Physical Hazard) primarily represents flammable materials. In the context of the National Fire Protection Agency (NFPA) 704 Hazard Identification System, the flame symbol can be seen on the top red diamond of the NFPA hazard diamond, indicating the level of fire hazard of a substance. This includes flammability and the temperature range for the flash point. Materials classified under this symbol easily ignite and burn in the presence of an ignition source. Such materials can include, but are not limited to, certain liquids, gases, and solids that can pose a fire risk.
Each hazard in the NFPA system is rated on a scale from 0 to 4, with 0 indicating no hazard and 4 representing extreme hazard. The other symbols, such as those standing for explosive materials, corrosive materials, or radioactive materials, are represented in other sections of the NFPA diamond.