UN 3257 Dodecane-12-lactam, molten UN Rec. 23rd rev. ed. (Shortinfo)

This designation shall only be used when the substance does not meet the criteria of any other class. Transport in cargo transport units other than in multimodal tanks shall be in accordance with standards specified by the competent authority of the country of origin.

For the purposes of documentation and package marking, the proper shipping name shall be supplemented with the technical name (see 3.1.2.8). For UN 3077 and UN 3082 only, the technical name may be a name shown in capital letters in column 2 of the Dangerous Goods List, provided that this name does not include "N.O.S." and that special provision 274 is not assigned. The name which most appropriately describes the substance or mixture shall be used, e.g.: UN 3082, ENVIRONMENTALLY HAZARDOUS SUBSTANCE, LIQUID, N.O.S. (PAINT) UN 3082, ENVIRONMENTALLY HAZARDOUS SUBSTANCE, LIQUID, N.O.S. (PERFUMERY PRODUCTS)