Section 173.217 - Carbon dioxide, solid (dry ice)(a) Carbon dioxide, solid (dry ice), when offered for transportation or transported by aircraft or water, must be packed in packagings designed and constructed to permit the release of carbon dioxide gas to prevent a buildup of pressure that could rupture the packagings. Packagings must conform to the general packaging requirements of subpart B of this part but need not conform to the requirements of part 178 of this subchapter.(b) For transportation by vessel:(1) Each transport vehicle and freight container containing solid carbon dioxide must be conspicuously marked on two sides "WARNING CO2 SOLID (DRY ICE)."(2) Other packagings containing solid carbon dioxide must be marked "CARBON DIOXIDE, SOLID-DO NOT STOW BELOW DECKS."(c) For transportation by aircraft:(1) In addition to the applicable marking requirements in subpart D of part 172, the net mass of the carbon dioxide, solid (dry ice) must be marked on the outside of the package. This provision also applies to unit load devices (ULDs) when the ULD contains dry ice and is considered the packaging.(2) The shipper must make arrangements with the operator for each shipment.(3) The quantity limits per package shown in columns (9A) and (9B) of the Hazardous Materials Table in § 172.101 of this subchapter are not applicable to dry ice being used as a refrigerant for other than hazardous materials loaded in a unit load device. In such a case, the unit load device must be identified to the operator and allow the venting of the carbon dioxide gas to prevent a dangerous build-up of pressure.(4) Dry ice is excepted from the shipping paper requirements of subpart C of part 172 of this subchapter provided alternative written documentation is supplied containing the following information: proper shipping name (Dry ice or Carbon dioxide, solid), class 9, UN number 1845, the number of packages, and the net quantity of dry ice in each package. The information must be included with the description of the materials.(5) Carbon dioxide, solid (dry ice), in quantities not exceeding 2.5 kg (5.5 pounds) per package and used as a refrigerant for the contents of the package is excepted from all other requirements of this subchapter if the requirements of paragraph (a) of this section are complied with and the package is marked "Carbon dioxide, solid" or "Dry ice", is marked with the name of the contents being cooled, and is marked with the net weight of the dry ice or an indication that the net weight is 2.5 kg (5.5 pounds) or less.(d) Carbon dioxide, solid (dry ice), when used to refrigerate materials being shipped for diagnostic or treatment purposes (e.g., frozen medical specimens), is excepted from the shipping paper and certification requirements of this subchapter if the requirements of paragraphs (a) and (c)(2) of this section are met and the package is marked "Carbon dioxide, solid" or "Dry ice" and is marked with an indication that the material being refrigerated is being transported for diagnostic or treatment purposes.73 FR 4718, Jan. 28, 2008, as amended at 82 FR 15882, Mar. 30, 2017 As amended at 82 FR 15882, 3/30/2017