What do shippers place on most hazardous materials packages to communicate the type of hazard?
Correct answer: A – Hazard warning labels
Federal labeling rules require applicable hazardous materials packages to display the labels specified for the material, unless an exception applies. These diamond-shaped labels communicate the material’s primary and, when required, subsidiary hazards. Labels belong on packages or securely attached tags; shipping papers separately provide the written shipping description.
Source: Nebraska Commercial Driver’s License Manual — § 9.3.2, “Package Labels”, 49 CFR § 172.400 — General labeling requirements

