49 CFR §172.400

1. (a)Except as specified in § 172.400a, each person who offers for transportation or transports a hazardous material in any of the following packages or containment devices, shall label the package or containment device with labels specified for the material in the § 172.101 table and in this subpart:
   1. (1)A non-bulk package;
   2. (2)A bulk packaging, other than a cargo tank, portable tank, or tank car, with a volumetric capacity of less than 18 m 3 (640 cubic feet), unless placarded in accordance with subpart F of this part;
   3. (3)A portable tank of less than 3785 L (1000 gallons) capacity, unless placarded in accordance with subpart F of this part;
   4. (4)A DOT Specification 106 or 110 multi-unit tank car tank, unless placarded in accordance with subpart F of this part; and
   5. (5)An overpack, freight container or unit load device, of less than 18 m 3 (640 cubic feet), which contains a package for which labels are required, unless placarded or marked in accordance with § 172.512 of this part.
2. (b)Labeling is required for a hazardous material which meets one or more hazard class definitions, in accordance with column 6 of the § 172.101 table and the following table: