Fire Diamond

The fire diamonds depict the dangers associated with hazardous chemicals. The system is based on the NFPA 704 standard, which is maintained by the U.S. based National Fire Protection Association. It was designed to allow emergency personnel to quickly identify the dangers of hazardous chemicals.

Figure 1: The squares in the fire diamond depict four hazard categories.

Red - Flammability

0: Will not burn.

1: Must be preheated to burn.

2: Ignites when moderately heated.

3: Ignites at normal temperatures.

4: Extremely flammable.

Blue - Health:

0: Like ordinary material.

1: Can cause significant irritation.

2: Can cause temporary incapacitation or residual injury.

3: Can cause permanent injury.

4: Can be lethal.

Yellow - Reactivity:

0: Normally stable.

1: Unstable if heated.

2: Violent chemical change possible.

3: May explode at high temperature or shock.

4: May explode at normal temperatures.

White - Special hazard

ALK = Alkaline

ACID = Acidic

COR = Corrosive

OX = Oxidizing

W = Reacts violently with water