The temporary storage (transshipment/crossdocking) of unopened ADR approved packaging is allowed according to the PGS 15 in a so-called Horsebox. This specifically involves loads of hazardous materials that are part of the logistics chain. The side and rear walls of the Horseboxes must have a fire resistance of 60 minutes based on a fire from outside to inside. Goods must be placed at least 50 cm from the open front and to a maximum height of 50 cm below the top of the side walls and back wall. In a 

Horse box may contain a maximum of 2000 kg of flammable liquids. It is not permitted to temporarily store substances of ADR classes 1, 2.3, 7, 5.2 (except LQ up to 1000 kg), 6.2 (except UN3291 and UN3373) and gas cylinders in a Horsebox. Also storage ADR substances packing group I is not 

allowed. For detailed regulations on the use of a Horsebox, please refer to chapter 5 of the PGS15.