Placards at the Scale House
You are hauling a straight truck with four pallets: 2,000 lb of UN1203 Gasoline, 3, PG II in 55-gallon drums; 1,500 lb of UN1263 Paint, 3, PG II in cans; 800 lb of UN1993 Flammable liquid, n.o.s., 3, PG III in pails; and 600 lb of UN3082 Environmentally hazardous substance, liquid, n.o.s., 9, PG III in jugs. You have a FLAMMABLE placard and a FLAMMABLE LIQUID placard available, but no CLASS 9 placard on the truck. At the scale house, an inspector asks to see your placards. You know that the 1,001-lb aggregate rule applies to some materials but not others, and you are not sure whether the gasoline alone forces placards on the whole load or only on its own pallets.
1. Determine which placards, if any, are required for this load, and explain the reasoning step by step.
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Start with the gasoline: UN1203 is a Table 2 material, and Table 2 materials must be placarded when the aggregate gross weight of all Table 2 materials in the load is 1,001 lb or more. The gasoline alone is 2,000 lb, so the FLAMMABLE placard is required for the gasoline. For Table 2, once the 1,001-lb threshold is met, the placard must be displayed for the material that meets it; the gasoline pallets must be placarded. Now the paint and the UN1993: both are Table 2 flammable liquids. The paint is 1,500 lb and the UN1993 is 800 lb. The aggregate of all Table 2 materials is 2,000 + 1,500 + 800 = 4,300 lb, well over 1,001 lb, so the FLAMMABLE placard is required and, depending on the placard scheme, the FLAMMABLE LIQUID placard may also be required for the paint and UN1993 portions. The UN3082 is a Table 1 material? No: UN3082 is a Class 9 material and is a Table 2 entry for placarding purposes only when it is a marine pollutant or otherwise listed; the 1,001-lb rule applies to Table 2, and 600 lb is below the threshold, so no CLASS 9 placard is required for that portion unless the material is also a marine pollutant in a quantity that triggers placarding. The practical answer: placard the gasoline with FLAMMABLE, placard the paint and UN1993 with FLAMMABLE or FLAMMABLE LIQUID as appropriate, and do not placard the UN3082 unless the rules for that specific material require it. The key exam point is that the 1,001-lb aggregate rule is applied per Table 2 category, not per pallet, and that Table 1 materials (like some Division 1.1, 2.3, 6.1 PG I, and 7 materials) require placards regardless of quantity.
2. The inspector says you may not proceed because the placards are not visible from the rear. How should you fix the problem, and what else should you check about placard placement?
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Placards must be displayed on both sides and both ends of the vehicle, so the rear of the truck must show the required placard as well. If the rear placard is missing or obscured, move or add a placard to the rear so it is visible. Also check that placards are at least 3 inches from any other marking, are not obscured by dirt, snow, or the load, and are placed on the exterior of the vehicle rather than on the cargo. If the truck has a tailgate or liftgate, the placard must be on the vehicle body, not on a surface that folds away. Check that the placards match the materials actually loaded: a FLAMMABLE placard on a truck carrying only Class 9 material is wrong, and a missing placard on a Table 1 material is a serious violation. Finally, verify that the placards are the correct size and color and that the hazard class number is in the lower corner. The inspector's concern is legitimate because responders approaching from the rear need to see the hazard before they see the cargo. Fix the rear placard, re-check all four sides, and only then proceed.