49 CFR § 172.402 - Additional labeling requirements.
(2)For other than Class 1 or Class 2 materials (for subsidiary labeling requirements for Class 1 or Class 2 materials see paragraph (e) or paragraphs (f) and (g), respectively, of this section), if not already labeled under paragraph (a)(1) of this section, shall be labeled with subsidiary hazard labels in accordance with the following table:
Subsidiary Hazard Labels
X - Required for all modes.
* - Required for all modes, except for a material with a flash point at or above 38 °C (100 °F) transported by rail or highway.
** - Reserved
*** - Impossible as subsidiary hazard.
(c) Cargo Aircraft Only label. Each person who offers for transportation or transports by aircraft a package containing a hazardous material which is authorized on cargo aircraft only shall label the package with a CARGO AIRCRAFT ONLY label specified in § 172.448 of this subpart.
(d) Class 7 (Radioactive) Materials. Except as otherwise provided in this paragraph, each package containing a Class 7 material that also meets the definition of one or more additional hazard classes must be labeled as a Class 7 material as required by § 172.403 and for each additional hazard.
(2) Each package or overpack containing fissile material, other than fissile-excepted material (see § 173.453 of this subchapter) must bear two FISSILE labels, affixed to opposite sides of the package or overpack, which conforms to the figure shown in § 172.441; such labels, where applicable, must be affixed adjacent to the labels for radioactive materials.
(1) Division 6.1, Packing Groups I or II, shall be labeled POISON or POISON INHALATION HAZARD, as appropriate.
(f) Division 2.2 materials. In addition to the label specified in column 6 of the § 172.101 table, each package of Division 2.2 material that also meets the definition for an oxidizing gas (see § 171.8 of this subchapter) must be labeled OXIDIZER.
(3) Class 8, must be labeled Corrosive.