what kind of hazardous material does a flame over a circle indicate

The “flame over a circle” symbol indicates oxidizing hazardous materials, not ordinary flammables, explosives, or self‑reactives.

What the symbol means

This pictogram is a white diamond with a red border, showing a black circle with flames on top of it.

It is used for substances classified as oxidizing gases, oxidizing liquids, or oxidizing solids.

In plain terms, oxidizers:

• Do not usually burn by themselves.
• Can release oxygen or other oxidizing substances.
• Can cause other materials to catch fire more easily or burn much more intensely.

So, when you see a flame over a circle, the hazardous material it indicates is oxidizers (oxidizing agents).

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