Which type of cargo is NOT covered by the new cargo securement rules?

Answer: C — Grain in a hopper

Grain in a hopper is not covered by the new cargo securement rules because this type of cargo is typically considered bulk cargo, which is governed by different regulations. Bulk materials like grain are usually loaded and transported in a way that does not require the same securement methods as palletized or packaged cargo. The regulations for bulk materials focus more on the prevention of spillage and maintaining the integrity of the containers rather than the specific securement techniques. On the other hand, the other types of cargo listed, such as concrete pipes, helium tanks, and drums of grease, are considered packaged or construction materials that require securement methods to ensure safe transportation. These cargo items necessitate specific tie-down and blocking requirements to prevent shifting during transit, which makes them subject to the new cargo securement rules.