Cyanide, Acid, and a One-Bay Straight Truck
At a repackager in Jackson you are loading a 26-foot straight truck for two deliveries. The pick list shows 4 drums of UN1689, SODIUM CYANIDE, Class 6.1, PG I, 100 lb each (400 lb) for a plating shop; 10 drums of UN1830, SULFURIC ACID, Class 8, PG II, 50 lb each (500 lb) for a battery recycler; and 6 pails of UN1263, PAINT, Class 3, PG II, 30 lb each (180 lb), also for the plating shop. All three stops are on the same route, and the truck has a single cargo space with no separate compartment or bulkhead partition. The loader has set the cyanide against the headboard and plans to put the acid directly behind it, then the paint. He tells you, "Nothing here is over 1,000 pounds, so this is a non-placarded load and we can stack it however we want."
1. Can the cyanide and the sulfuric acid ride in the same truck? Explain the governing rule.
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No. 49 CFR 177.848(d) specifically prohibits loading or storing cyanides or cyanide mixtures with acids. The hazard is real and fast: an acid leak contacting cyanide salt liberates hydrogen cyanide gas, which can kill in an enclosed space and is dangerous even in the open. The prohibition is not satisfied by putting the acid behind the cyanide, by dunnage, or by a barrier in the same cargo space; the only compliant options are separate vehicles or separate trips. Under the segregation table, the paint is not a prohibited pair with either the acid or the cyanide, so it can travel with either shipment. The single-truck plan to three stops therefore has to be broken: run the cyanide to the plating shop on one trip and the acid to the recycler on another, or tender the acid to a different carrier. Get the change documented with dispatch before anything is loaded.
2. Is the loader right that 1,080 pounds total means no placards? Work through the placarding for the load as planned, and then for the split shipments.
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He is wrong on the threshold and wrong to treat it per material. The 1,001 lb trigger in 172.504 is the aggregate gross weight of all Table 2 materials on the vehicle. Class 3, Class 8, and this 6.1 solid are all Table 2, since sodium cyanide is not a Hazard Zone A or B inhalation hazard. 400 plus 500 plus 180 is 1,080 lb, which is above the threshold, so the planned load would need POISON, CORROSIVE, and FLAMMABLE placards, or the DANGEROUS placard substituting for two or more Table 2 classes. After the split, the cyanide-only trip is 400 lb of a 6.1 solid in non-bulk drums, under 1,001 lb, so no placard is required. The acid and paint together are 680 lb, also under the threshold, so no placard there either. Placarding, though, is not the reason to split the load; the segregation prohibition is, and it applies no matter how small the quantities are.
3. Describe how you would load and secure the cyanide shipment once the loads are split.
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Drums go upright with the cyanide blocked against the headboard or a solid wall section, braced side to side with dunnage or load bars, and braced front and back so nothing can shift under braking or emergency swerving; a 100 lb drum becomes a missile at highway speed, and a ruptured cyanide drum is a life-safety problem, not a cargo-damage problem. Inspect each drum before it goes on: reject anything stained, weeping, dented at the chime, or missing a closure, and never load a leaking package hoping it will ride. Keep the load dry, because water plus cyanide salt is a hazard, and cover it if the truck is not fully enclosed. Make sure the cyanide never shares the vehicle with the acid, even at opposite ends. Record the seal number on the bill of lading and confirm the route does not cross a restricted tunnel or bridge.