Placarding Thresholds and Any-Quantity Materials
Placarding requirements in 49 CFR Part 172 Subpart F depend on the HazMat class and quantity. The 1,001-lb rule: for Table 2 materials (most HazMat classes), placards are required only when the total weight of all HazMat in a single shipment reaches or exceeds 1,001 lbs (454 kg). Below 1,001 lbs of a Table 2 material, no placard is required (but the shipping papers and markings still apply). Table 1 materials — the most hazardous classes — require placards regardless of quantity: any amount of a Table 1 material requires placarding. Table 1 materials include: Division 1.1, 1.2, 1.3 explosives; Division 2.3 poison gas; Class 4 flammable solids (certain); Division 6.1 toxic liquids and solids (packing group I); Class 7 radioactive in certain categories. The 'dangerous' placard: when carrying two or more Table 2 classes simultaneously, a carrier may use a single DANGEROUS placard instead of class-specific placards — but only when the combined weight is below 1,001 lbs for each individual class. If any single class reaches 1,001 lbs, its specific placard is required. The DANGEROUS placard is an omnibus placard for mixed loads that avoids requiring multiple different placards on a single vehicle.