Overloaded axle after a late pallet substitution
You are loading a rigid truck (3 axles, maximum permissible gross weight 26 t, front axle limit 7.5 t, rear bogie limit 19 t) for a run from Plovdiv to Ruse. The consignment is 18 pallets of UN 1263 paint (packing group II, 4G fibreboard boxes on EUR pallets), declared gross 14 800 kg, plus 6 pallets of UN 1950 aerosols (2.1) at 3 200 kg. At the last minute the customer substitutes 4 paint pallets with 4 pallets of UN 3082 environmentally hazardous liquid, n.o.s. (9, PG III) that are denser: each weighs 1 450 kg instead of 800 kg. The loader has already placed the aerosols in the middle of the bed and the paint at the rear doors. There is no weighbridge on site. The driver is asked to sign the transport document and leave immediately to keep a delivery slot.
1. What weight and load-distribution checks must the driver make before signing anything, and what is the likely outcome?
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The substitution adds 4 × (1450 − 800) = 2 600 kg, so the declared total rises from 18 000 kg to about 20 600 kg of goods. That is still below 26 t gross only if the tare plus fuel and crew are under roughly 5.4 t - plausible for a rigid but not something to assume. The driver cannot verify axle loads without a weighbridge or certified on-board weighing, so the honest answer is: refuse to depart until the load is weighed at the nearest public weighbridge. Distribution matters as much as total: the dense UN 3082 pallets should go low and near the rear bogie, not at the tail behind the rear axle line, and the aerosols must not be buried under heavy pallets. The rear bogie at 19 t is the binding constraint on a 26 t rigid. If weighing shows the bogie over 19 t, part of the load must be offloaded or redistributed forward; if gross exceeds 26 t, the vehicle is simply not usable for this consignment and a second vehicle is needed. Signing the document first would make the driver party to an overload.
2. How should the pallets be rearranged, and what segregation issue arises from the aerosol placement?
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The four heavy UN 3082 pallets should be moved to the floor of the bed, spread across the rear bogie area and against the headboard side of the load where they cannot slide, with the lighter paint pallets above or in front of them. Aerosols (UN 1950, division 2.1) should not be crushed or enclosed by heavier goods, and must be kept away from any heat source and from the exhaust area. Under ADR mixed-loading logic, class 2.1 aerosols and class 3 paint are both flammable, so there is no formal segregation table conflict between 2.1 and 3, but the practical rule is that aerosols are fragile pressure receptacles: they belong on top or in a dedicated bay with nothing stacked on them. The environmentally hazardous UN 3082 pallets must be checked for leaking closures and kept so that any spill cannot run onto the aerosols. The driver should also confirm the aerosols are not loaded next to any oxidising or corrosive consignment if one is added later.
3. What document checks must accompany the signature, and what if the papers do not match the load?
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Before signing, the driver checks that the transport document lists, for each UN number, the proper shipping name, class, packing group, number and description of packages, total quantity, and the tunnel restriction code. UN 3082 requires the environmentally hazardous mark and the document must reflect class 9 and PG III; the aerosols require class 2.1 and the correct description. The driver also checks that the placards and orange plates match what is actually on the bed - after the substitution, the vehicle still needs the class 3 and 2.1 placards, plus class 9 for the UN 3082. If the document still shows the old paint quantities, or omits the class 9 entry, the driver must not sign. The correct action is to have the consignor issue a corrected document and a corrected placarding set; the driver may note the discrepancy but cannot simply amend the consignor's declaration. Departing with a false document exposes the driver to liability as well as the consignor.