Marking, Labeling, and Placarding
Marking and labeling packages
Marking is information printed directly on the package; labeling uses the diamond-shaped hazard labels. A package of hazardous material generally must show the proper shipping name and identification number, and must bear the label for its hazard class. Labels are specific: a 3 label is red, a 8 label is black and white with a corrosive symbol, a 2.1 label is red with a flame. Labels must be durable, legible, and located so they are not obscured.
Placards on the vehicle
Placards are the large diamond signs on the vehicle. The general rule is that a vehicle carrying 1,001 pounds or more aggregate gross weight of a Table 2 material, or any quantity of a Table 1 material, must be placarded. Table 1 includes materials such as certain explosives, poison gases, and dangerous when wet materials. Table 2 covers most other regulated materials. Placards must be on both sides and both ends of the vehicle, and must match the material loaded.
Traps to watch
A frequent trap is confusing the 1,001-pound threshold with a per-package limit, or assuming a placard is required for every quantity. Another is the DANGEROUS placard, which may be used only for materials that require more than one placard, and only when the shipment contains two or more categories. Questions also test placard visibility and cleanliness: a placard that is dirty, faded, or turned inward does not satisfy the rule.
Worked example
A truck carries 600 pounds of a Table 2 flammable liquid and 500 pounds of a Table 2 corrosive. Neither alone reaches 1,001 pounds, but together the aggregate is 1,100 pounds, so the vehicle must be placarded for both classes. The DANGEROUS placard may be used in place of the two class placards.
Rule of thumb
Table 1: any amount triggers placarding. Table 2: add the weights; 1,001 pounds or more triggers placarding.