Dangerous Goods and Cargo Security
Classification and the shipper's role
The dangerous goods framework rests on classification into hazard classes and divisions, proper shipping names, UN numbers, packing groups, and compatibility. The shipper classifies, packs, marks, labels, and documents; the operator accepts, checks, loads, and segregates. Candidates must know that the operator has an independent acceptance duty - it cannot simply trust the shipper's declaration. Traps include assuming that a passenger-carried item is permitted because it is small, or that an item is forbidden because it sounds hazardous; lithium batteries, aerosols, and certain medical items illustrate the nuance. Another trap confuses cargo aircraft allowances with passenger aircraft prohibitions.
Security of cargo and mail
Cargo security covers known consignor schemes, screening, chain of custody, and access control. The principle is that cargo must be protected from unauthorised interference from the point screening is completed until it is loaded. Questions often describe a break in the chain of custody and ask what is required: the answer is usually re-screening or secure re-establishment of the chain, not merely a visual check.
Rule of thumb
When a scenario presents an item, ask three questions: is it forbidden, is it permitted with limits, or is it permitted only with operator approval? Worked example: a passenger presents a spare lithium battery in checked baggage. Spare batteries are not permitted in checked baggage; they must be carried in the cabin, protected against short circuit, and within state and operator limits. The correct response is to require repacking to carry-on, not to confiscate outright.