NFPA 704 - diamond ratings NFPA

the four-diamond legend found on buildings and objects, which reflects the hazard degree of the contents
NOTE: Properly called NFPA (National Fire Protection Association) diamonds and based on the 704 standard developed by the NFPA, these symbols are used to provide a gross indication of flammability, instability and other data. They are similar in intent to the class-divisions numbering found on dangerous goods placards and labels. The four sections contain ratings (ranging from one to four with four as the most severe) as follows:
⎯ The upper triangle (red) is the fire hazard and flash point rating.
⎯ The left triangle (blue) is the health hazard rating.
⎯ The right triangle (yellow) is the reactivity rating.
⎯ The lower triangle (white) is used to reflect any specific hazard indication.

Application Area: Freight, Logistics and Commercial Vehicle Operations