Cyanide, Acid, and a Signed Waiver in Kansas City
At a Kansas City warehouse you are loading a 53-foot van for a 6 a.m. delivery in Joplin. Three pallets are staged: 8 drums of UN1830, Sulfuric acid, Class 8, PG II; 12 drums of UN1689, Sodium cyanide, Class 6.1, PG I; and 10 carboys of UN1791, Hypochlorite solution, Class 8, PG II. The dispatcher's load plan puts the cyanide at the nose, the acid against the rear doors, and the hypochlorite in the middle; he argues the drum walls are thick and a leak would only run downhill to the doors. The trailer floor is plywood with an old, sprung board and a crusted stain from an earlier load. The shipper's agent offers to sign a note accepting all responsibility if you load it as planned. The customer has threatened to reject the shipment if it is late.
1. Do you load as planned? Identify each incompatible pair and the rule that controls.
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You refuse the load. There are two independent incompatibilities here, and either one is enough.
First, cyanide with acid. 49 CFR 177.848(c) prohibits loading or storing cyanides or cyanide mixtures with acids if a mixture of the contents could cause a dangerous evolution of heat or gas. Sodium cyanide plus sulfuric acid releases hydrogen cyanide, a deadly gas. That chemistry is also why the cyanide is Class 6.1 PG I.
Second, hypochlorite with acid. Acidifying a hypochlorite solution releases chlorine gas. Same result, different gas.
On top of the segregation problem, the 6.1 PG I cyanide is a Table 1 material that requires a POISON placard in any quantity regardless of weight.
Do not sign the shipping paper. Your signature certifies the load is properly described and in condition for shipment; loading incompatible materials makes that certification false.
2. The dispatcher says the nose-middle-rear arrangement solves the problem. Answer him with reasoning, not just a refusal.
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Position inside a single trailer is not segregation under the rule. The regulation says the materials may not be loaded or stored with one another; it does not say 'keep them apart.' The prohibition is triggered by the possibility of mixing, and a van offers plenty of ways for that to happen.
Walk him through the failure paths. A drum that has been dropped or has a corroded bung weeps in transit; liquid migrates along a plywood floor with a sprung board, pools at the doors, and vapor fills the trailer. None of that respects an imaginary barrier between pallets. A hard brake or a bad pavement joint is enough to shift drums together.
The fix is structural, not spatial: split the shipment into two vehicles, or leave one material behind, or have the shipper hold the cyanide for a dedicated run. Those are the only options that eliminate mixing potential.
3. The agent's signed note accepting responsibility - what does it change?
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It changes nothing that matters to you. A private indemnity letter does not waive a federal prohibition, and it will not protect you from an out-of-service order, a civil penalty, or personal exposure after an incident. Loading is a shared responsibility between the hazmat employee and the carrier; the shipper cannot sign away your duty.
Handle it in a way that protects you practically as well as legally. Refuse in front of a witness, state the reason as incompatibility under 177.848(c), and put the refusal in an email or text to your company the same shift. Ask the shipper for a second trailer or a split load, and if a second trailer is used, placard and paper each vehicle on its own contents rather than the combined shipment.
If a supervisor directs you to load it anyway, call your safety department before you move a wheel. Do not sign the shipping paper and do not depart with a load you know is prohibited.