Which item is permitted as dangerous goods in checked baggage only?

• A. Ammunition
• B. Mercury Barometer
• C. Medical Oxygen
• D. Lithium Battery Cells

Answer: (A)

A key idea here is where dangerous goods are allowed on a passenger flight. Ammunition is the one item that is permitted in checked baggage under strict conditions: it must be for sporting use, not loaded in a firearm, packed in a sturdy container, and kept within the allowed quantity limits. It cannot be carried in the cabin, which is why it’s described as allowed in checked baggage only. The other items pose hazards that restrict their transport on passenger aircraft: a barometer containing mercury is not allowed due to the toxicity of mercury; medical oxygen is not permitted in checked baggage because compressed gas presents a safety risk; lithium battery cells carry a fire hazard and are not allowed in checked baggage (they’re generally restricted to carry-on with specific allowances).