Which symbol describes mass fire?

• A. An inverted triangle with the number 3 inside
• B. An inverted triangle with the number 2 inside
• C. A circle with a flame
• D. A square with the number 3

Answer: (A)

Mass fire is conveyed by a downwards-pointing triangle with a number inside, and the number 3 is the designation used for this hazard. The inverted triangle shape signals a mass-related danger, while the 3 specifies that the risk is a mass fire scenario—where a fire could involve a large quantity of material at once. This combination quickly communicates the type and seriousness of the hazard to anyone handling or responding to the munitions.

The circle with a flame is a general fire symbol and doesn’t indicate that the danger involves a mass event. A square with a 3 isn’t the standard symbol for this particular hazard either, and the inverted triangle with 2 would point to a different category. So the inverted triangle with 3 is the correct symbol for mass fire.