Tunnel code conflict on a cross-country route
You are planning a run from Sofia to a delivery point beyond a long mountain tunnel. The load is 12 × 220-litre drums of UN 1203 petrol (class 3, PG II, total 2 640 litres) and 8 cylinders of UN 1005 ammonia, anhydrous (class 2.3, 8 × 50 kg). The tunnel on the direct route is signed with restriction code category C. The alternative road adds 95 km and crosses a lower pass with no tunnel. The dispatcher says the vehicle has the correct orange plates and that the driver should just take the direct route because the load is 'only a few tonnes'. The driver has a delivery window of 6 hours; the direct route takes 4 hours, the detour 5 hours 40 minutes including a mandatory break.
1. How does the tunnel category C restriction apply to this load, and what must the driver decide?
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Tunnel category C prohibits the passage of goods that carry tunnel restriction codes C, D or E; goods with codes B, A or no code may pass. The driver must therefore derive the tunnel restriction code for each consignment, not guess from the class. Petrol in drums (UN 1203, PG II, in packaging) normally carries tunnel code D, which is prohibited in category C. Anhydrous ammonia (UN 1005) normally carries code C, also prohibited in category C. So the direct route is closed to this vehicle regardless of the small tonnage - the restriction is about the goods, not the quantity, unless a specific quantity threshold applies to the entry. The dispatcher's 'only a few tonnes' argument is wrong. The driver must take the detour, or split the load, or obtain a route with no restricted tunnel. The 5 h 40 min detour still fits the 6-hour window only if the mandatory break is genuinely taken, so the schedule must be re-planned rather than compressed.
2. What if the tunnel sign shows category E instead of C?
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Category E is the most restrictive of the ordinary categories: it excludes goods with codes B, C, D and E, admitting only goods with code A or no tunnel code. Under category E, both the petrol (code D) and the ammonia (code C) are prohibited, so the position is worse, not better, and the detour is mandatory. The driver should also check whether the tunnel is one of the special cases where an outright prohibition applies to certain classes regardless of code, for example some very large quantities. The practical lesson is that the driver must read the actual sign and match it against the codes on the transport document, because a category that looks permissive (C) already excludes this load, and a stricter one (E) excludes even more.
3. What should the driver record and communicate before departing?
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The driver should record the tunnel restriction codes from the transport document, the category on the sign, and the chosen route, and inform the dispatcher in writing that the direct route is prohibited for this load. The delivery window should be renegotiated with the consignee, not met by skipping the break. If the dispatcher insists on the direct route, the driver must refuse: the prohibition is a legal restriction, and the driver is personally exposed. The driver should also confirm the vehicle carries the correct orange plates for class 3 and class 2.3, the extinguishers, and the PPE for ammonia - the detour over a pass may mean colder conditions and a longer response time if a cylinder leaks.