Division 4.1 Packing Group 2-3 excluding self-reactive substances is permitted on aircraft only in what quantity?

• A. They are always allowed on planes
• B. They require no packaging restrictions
• C. They are permitted only in limited quantities
• D. They are never allowed on planes

Answer: (C)

Air transport of explosives is tightly controlled, and only smaller amounts are allowed under special provisions. For Division 4.1 substances that are in Packing Groups II or III, you can ship them by air only if they fall under Limited Quantities. This means there is a defined maximum amount per package or per shipment and specific packaging, labeling, and documentation requirements to keep risk low in case of an incident. Self-reactive substances are excluded from this limited-quantity allowance, so they don’t get the same latitude. The other options would ignore these safety controls or misstate the requirements, whereas limited quantities reflect the safety-based permission that applies to these lower-risk explosive classifications.