Which UN labeling number would indicate a substance that readily yields oxygen to support combustion?

Which UN labeling number would indicate a substance that readily yields oxygen to support combustion?

• A. 3
• B. 7
• C. 9
• D. 5

Answer: (D)

Oxidizers are substances that readily release oxygen to support combustion. They don’t burn on their own, but they make fires burn more intensely by providing the oxygen that fuels the reaction. In UN labeling, oxidizers are identified by the hazard class that corresponds to oxidizing agents, which is distinct from other hazard classes such as flammable liquids, radioactive materials, or miscellaneous dangerous goods. Therefore, the label or numbering that indicates an oxidizer points to a substance that will promote and accelerate combustion. The other hazard classes shown by the remaining options describe different dangers (flammable liquids burn, radioactive materials involve radiation, and miscellaneous dangerous goods cover a wide range of hazards) and do not specifically indicate an oxygen-yielding oxidizer.

Oxidizers are substances that readily release oxygen to support combustion. They don’t burn on their own, but they make fires burn more intensely by providing the oxygen that fuels the reaction. In UN labeling, oxidizers are identified by the hazard class that corresponds to oxidizing agents, which is distinct from other hazard classes such as flammable liquids, radioactive materials, or miscellaneous dangerous goods. Therefore, the label or numbering that indicates an oxidizer points to a substance that will promote and accelerate combustion. The other hazard classes shown by the remaining options describe different dangers (flammable liquids burn, radioactive materials involve radiation, and miscellaneous dangerous goods cover a wide range of hazards) and do not specifically indicate an oxygen-yielding oxidizer.