A driver is transporting a non-bulk shipment of UN1263, Paint (Class 3, PG II), weighing 800 pounds, and UN1830, Sulfuric acid (Class 8, PG II), weighing 300 pounds. Both materials are in separate packages. Which placards are required on the vehicle?

Correct answer: A. Only FLAMMABLE and CORROSIVE placards.

This scenario involves two Table 2 materials. The placarding threshold for Table 2 materials is 1,001 pounds aggregate gross weight. Since the total weight is 800 + 300 = 1,100 pounds, which exceeds 1,001 pounds, placards are required. Because neither material is in a bulk packaging, and each material individually is less than 1,001 pounds, the 'DANGEROUS' placard rule (49 CFR 172.504(b)) would typically apply. However, 49 CFR 172.504(c) states that if a freight container, unit load device, transport vehicle or rail car contains 1,000 kg (2,205 pounds) or more of a single non-bulk hazardous material, it must be placarded with the specific placard for that material. But here, neither material meets the 2,205 lb threshold *individually*. The key is 49 CFR 172.504(b) which allows the use of 'DANGEROUS' placard UNLESS a specific placard is required for a specific material in the load. Since both are Table 2 materials and their combined weight exceeds 1,001 lbs, and individually they are less than 2,205 lbs, the DANGEROUS placard would seem applicable. However, there's an exception: if a transport vehicle contains 1,000 kg (2,205 lbs) or more of a single non-bulk hazardous material, it must be placarded with the specific placard for that material. This is not the case here. The 'DANGEROUS' placard is used for mixed loads of non-bulk Table 2 materials that total 1,001 lbs or more, *unless* there is 1,000 kg (2,205 lbs) or more of a single Table 2 material. Since neither material reaches 2,205 lbs individually, the DANGEROUS placard should be used. Wait, let me re-evaluate based on 49 CFR 172.504(b). It says: 'A transport vehicle or freight container containing non-bulk packages of two or more categories of hazardous materials that require placarding under Table 2, may be placarded with a DANGEROUS placard instead of the specific placards for each of the materials when: (1) The aggregate gross weight of the hazardous materials is 1,001 pounds (454 kg) or more; and (2) The transport vehicle or freight container does not contain 1,000 kg (2,205 pounds) or more of a hazardous material of any one category subject to the provisions of Table 2.' In this case, the total is 1,100 lbs, satisfying (1). Neither material is 2,205 lbs or more, satisfying (2). Therefore, a DANGEROUS placard is permitted. The question asks 'Which placards ARE required', implying the most specific correct placarding. The 'DANGEROUS' placard is PERMITTED, but specific placards are always an option. The 'DANGEROUS' placard is a convenience. If you use specific placards, you must use them. The most accurate answer is to use the specific placards if the sum is over 1,001 lbs. This is a common point of confusion. Let's re-read the regulations carefully: '...may be placarded with a DANGEROUS placard *instead of the specific placards for each of the materials*...' This means if you use DANGEROUS, you don't use specific. But the question is 'Which placards are REQUIRED'. If the total is over 1,001 lbs, specific placards are required unless the DANGEROUS option is chosen. The most direct interpretation for 'required' when the threshold is met is the specific placards for each class. So, FLAMMABLE for Paint and CORROSIVE for Sulfuric Acid. This is a tricky point in the regulations. The 'DANGEROUS' placard is an *option* if certain conditions are met, allowing a single placard instead of multiple specific ones. However, specific placards are always acceptable and are considered 'required' if the threshold is met. For exam purposes, if specific placards are available and the threshold is met, they are considered correct. The correct interpretation: Since the aggregate gross weight of Table 2 materials (800 lbs + 300 lbs = 1,100 lbs) exceeds 1,001 pounds, placarding is required. For non-bulk packages of two or more categories of Table 2 materials, you *may* use the DANGEROUS placard *instead of* the specific placards, provided no single material is 2,205 lbs or more. However, using the specific placards (FLAMMABLE for the paint and CORROSIVE for the sulfuric acid) is always a compliant option when the 1,001 lb threshold is met. Since 'FLAMMABLE' and 'CORROSIVE' placards represent the specific hazards and are always permissible when their thresholds are met (which they are, as part of the overall 1,001 lb aggregate), this is the most accurate and specific answer for 'required placards'. The 'DANGEROUS' placard is a permissive alternative, not a mandatory one if specific placards are also applicable. Let's simplify the rule for the exam: If the total of Table 2 materials is over 1,001 lbs, you can either use specific placards for every material (if no single material is 2,205 lbs or more), or you can use the DANGEROUS placard. Both are compliant. However, if the question asks what IS required, and specific placards are an option, they are generally the 'more correct' answer as they provide more specific hazard communication. Often, questions are framed to test the understanding that specific placards are always an option when thresholds are met. Re-evaluating for common exam interpretation: The 'DANGEROUS' placard is a convenience placard. If the total weight of Table 2 materials is over 1,001 lbs and no single Table 2 material weighs 2,205 lbs or more, then the DANGEROUS placard *may* be used *instead of* the specific placards. However, the specific placards for each material *are* required if the 1,001 lb aggregate threshold is met. If you choose to use the DANGEROUS placard, you don't use the specific ones. If you don't use the DANGEROUS placard, you use the specific ones. The question asks 'Which placards are REQUIRED'. When the aggregate threshold is met, specific placards are the default requirement unless the DANGEROUS option is taken. Therefore, FLAMMABLE and CORROSIVE placards are required. Final check on the rule: 49 CFR 172.504(b) states that a vehicle containing non-bulk packages of two or more categories of hazardous materials that require placarding under Table 2 *may* be placarded with a DANGEROUS placard *instead of* the specific placards. This means the specific placards (FLAMMABLE and CORROSIVE) are the *default requirement* once the 1,001 lb aggregate threshold is met. The DANGEROUS placard is an *alternative*. So, FLAMMABLE and CORROSIVE are required. Math: Paint (Class 3, PG II): 800 lbs Sulfuric Acid (Class 8, PG II): 300 lbs Total Table 2 materials = 800 + 300 = 1,100 lbs. Since 1,100 lbs > 1,001 lbs, placarding is required. Neither material individually exceeds 2,205 lbs. Therefore, specific placards for each (FLAMMABLE and CORROSIVE) are required. The DANGEROUS placard is an *option* for mixed loads under these conditions, but specific placards are always acceptable and are the primary way to communicate specific hazards. Correct Answer is B. Explanation for B: Since the total aggregate gross weight of the Table 2 hazardous materials (800 lbs of Paint + 300 lbs of Sulfuric acid = 1,100 lbs) exceeds the 1,001-pound threshold, the vehicle must be placarded. For non-bulk packages, specific placards for each hazard class (FLAMMABLE for Class 3 and CORROSIVE for Class 8) are required. While a DANGEROUS placard *may* be used as an alternative for mixed loads of Table 2 materials under 2,205 lbs per individual material, the specific placards are always permissible and are considered the direct requirement when the threshold is met. Option Notes: A: A DANGEROUS placard *may* be used as an alternative for mixed Table 2 loads if no single material is 2,205 lbs or more, but specific placards are also required/permissible and convey more precise information. In this context, 'required' means the specific placards. B: With an aggregate of 1,100 lbs of Table 2 materials, specific placards (FLAMMABLE for Class 3 and CORROSIVE for Class 8) are required. C: A FLAMMABLE placard is required for the paint, but a CORROSIVE placard is also required for the sulfuric acid. D: A DANGEROUS placard is an *alternative* for mixed Table 2 loads, not typically used *in addition* to specific placards for individual materials when the specific placards are already mandated by weight thresholds. This question highlights a critical nuance in placarding rules: the difference between 'may be placarded' (permissive, like the DANGEROUS placard) and what placards are 'required' (the specific ones when thresholds are met). Final Decision on Answer: B. The question asks what is *required*. When the 1,001 lb aggregate threshold for Table 2 materials is met, specific placards (FLAMMABLE and CORROSIVE) are required. The DANGEROUS placard is an *option* to simplify if desired, but not the sole requirement.