Mixed loading of class 1 and class 5.1 in one vehicle
A vehicle is offered a part load for a regional run: 6 boxes of UN 0027 black powder (class 1, division 1.1D, 24 kg net explosive content) and 10 boxes of UN 1942 ammonium nitrate fertiliser (class 5.1, PG III, 250 kg). The consignor says both are 'just powders' and wants them on one vehicle to save a trip. The vehicle is a box body with a wooden floor, no fire suppression beyond two 6 kg ABC extinguishers, and the driver's ADR certificate covers packages only, not class 1 in the explosives specialist sense. The route passes a fuel depot and a school.
1. Is this mixed load permitted, and what are the decisive factors?
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The decisive point is that class 1 explosives and class 5.1 oxidising substances are a classic incompatible combination: an oxidiser can feed and accelerate the decomposition or combustion of an explosive, and black powder is itself sensitive. The mixed-loading rules for class 1 are stricter than the general segregation table and generally prohibit loading class 1 goods with oxidising substances unless a specific exemption applies and the competent authority has authorised it. Here there is no such authorisation. The consignor's 'just powders' description is meaningless in ADR terms. The load should be refused as a mixed consignment, or split onto two vehicles with the class 1 consignment carried under the full class 1 regime. The wooden floor and the absence of fire suppression make the combination worse, not better.
2. What competence and vehicle requirements apply to the class 1 part alone?
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Carrying class 1 goods requires the driver to hold the class 1 extension to the ADR certificate, and the vehicle must meet the class 1 construction and equipment requirements, including the appropriate fire suppression and the correct placarding and orange plates. The transport document must show the division, compatibility group, net explosive mass and the tunnel restriction code. The driver in this scenario holds only the packages certificate, so even the class 1 part cannot lawfully be carried by this driver. The class 5.1 part alone could be carried by this driver, but the ammonium nitrate must be kept away from combustible material and from any heat source, and the vehicle must carry the class 5.1 placards. The correct answer to the consignor is: split the load, and for the class 1 part use a driver and vehicle that meet the class 1 requirements.
3. What route and supervision issues arise if the consignor insists on one vehicle?
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If the consignor insists, the driver must refuse. A route past a fuel depot and a school is exactly where the consequences of an incident with class 1 goods are worst, and the tunnel and route restrictions for class 1 must be checked before any movement. Supervision and parking rules for class 1 are stricter than for ordinary packages, and an unsupervised overnight stop would not be acceptable. The driver should record the refusal and the reason, and offer the split-load solution. The dispatcher should be told in writing that the combination is prohibited, so that the refusal is not later presented as the driver's delay.