ADR tank is a special type of tank wagon that is approved for transporting dangerous goods by road.

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ADR stands for "Accord européen relatif au transport international des Marchandises Dangereuses par Route", which is an international agreement that regulates the transport of dangerous goods by road. ADR tanks must meet strict safety requirements and be equipped with special safety features, such as fire extinguishing systems and leakage protection, to minimize the risk of accidents during transport.