Meanings
plural fire diamonds
- informalA coloured diamond symbol identifying the specific risks posed by a hazardous material according to the NFPA 704 classification.
Many facilities that manufacture, use, or store hazardous materials use the NFPA fire diamond to communicate fire hazards. Indeed, numerous cities have local regulations or ordinances requiring the use of fire diamonds or equivalent communication/warning labels.
1999, Gayle Woodside, Hazardous Materials and Hazardous Waste Management, page 133
Origin
One of the four divisions of the diamond-shaped symbol indicates flammability.
Full word history & related roots →Cite this entry
fire diamond. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/fire%20diamond
“fire diamond.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/fire%20diamond. Accessed November 4, 2026.
WatkinsX Dictionary, s.v. “fire diamond,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/fire%20diamond.
Source: fire diamond on Wiktionary, CC BY-SA 4.0.