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622 Mailable Hazardous Materials

622.1 General

As shown in Exhibit 621.1, almost all hazardous materials are prohibited in international mail. Under specific circumstances, only biological substances, limited amounts of radioactive materials, and certain magnetized materials are eligible to be sent in international mail.

622.2 Biological Substances, Division 6.2

Infectious and noninfectious biological substances are permitted in international mail subject to the provisions that apply to domestic mail in 346.2 and DMM 601.8. In addition, the following requirements apply:

  1. Biological substances are prohibited from international mail by certain countries. To determine if a prohibition exists for a specific country, check the Individual Country Listings in the IMM.
  2. Mailable infectious substances must be sent by registered First-Class Package International Service using Registered Mail service. Nonregulated materials defined in 346.234 and exempt human or animal specimens defined in 346.12d are mailable by First-Class Package International Service when properly packaged as described in 346.32.
  3. Biological substances can be sent to or received by only the following types of institutions when permission has been granted:
    1. Laboratories of local, state, and federal government agencies.
    2. Laboratories of federally licensed manufacturers of biological products derived from bacteria and viruses.
    3. Laboratories affiliated with or operated by hospitals, universities, research facilities, and other teaching institutions.
    4. Private laboratories licensed, certified, recognized, or approved by a public authority.

    Permission to mail biological substances must be obtained prior to mailing. Qualifying institutions wishing to mail biological substances must submit a written letter of application on its organizational letterhead to the following address:

    MANAGER PRODUCT CLASSIFICATION
    US POSTAL SERVICE
    475 L’ ENFANT PLZ SW RM 4446
    WASHINGTON DC 20260–4446

    The application must state the institution’s nature of work, the identity and qualifications of the prospective recipient, and the number of packages to be mailed.

  4. Mailable infectious substances are limited to 50 ml for liquids or 50 g for solids, per mailpiece and must be packaged in accordance with Packaging Instruction 6C in Appendix C, DMM 601.10.17.5, and the additional requirements in IMM 135.31 and 135.41.
  5. Nonregulated materials and exempt human or animal specimens must be packaged in accordance with Packaging Instructions 6G and 6H in Appendix C, DMM 601.10.17, and the additional requirements in IMM 135.32 and 135.42.
  6. A shipper’s declaration for dangerous goods is required. See 326 and 725.3.

622.3 Radioactive Materials, Class 7

Class 7 radioactive materials are permitted in international mail subject to the limits in 347 and the following conditions:

  1. Radioactive materials may be sent only to those countries that have expressed a willingness to accept them. For specific details, consult the Individual Country Listings in the IMM.
  2. Each radioactive materials shipment must be sent as a registered airmail letter package.
  3. Each shipment must comply with both the International Atomic Energy Agency Regulations and the specifications contained in 347 and this section.
  4. Mailable radioactive materials must be packaged in accordance with Packaging Instruction 7A in Appendix C and the requirements specified in IMM 135.5.
  5. The sender and recipient of each radioactive materials shipment must receive prior authorization from the appropriate regulatory authorities within their countries.
  6. A white package label bearing the French words “Matieres Radioactives” (Radioactive Materials) must be securely affixed, taped, or gummed to the address side of each mailpiece containing radioactive materials. The sender is responsible for supplying and affixing this label to the mailpiece.
  7. The address side of each mailpiece must bear the following endorsements in bold letters: “Return to Sender in Case of Nondelivery” and “Radioactive Materials, Quantities Permitted for Movement by Post.”
  8. A shipper’s declaration for dangerous goods is required. See 326 and 725.3.

622.4 Magnetized Materials

Magnetized materials, as defined in 349.24, are prohibited in international mail except for those that cannot cause a compass deviation at a distance of 7 feet or more. Mailable magnetized materials must be prepared for mailing following Packaging Instruction 9B in Appendix C.

622.5 Lithium and Lithium-ion Cells and Batteries — General

Only lithium batteries under 622.51 and 622.52 that are properly installed in the equipment they operate may be sent internationally or to and from an APO, FPO, or DPO location, if permitted by the international destination country or APO, FPO, or DPO location. Lithium batteries that are packed with the equipment or lithium batteries sent separately from equipment are prohibited. Damaged or recalled batteries are prohibited and may not be mailed internationally under any circumstances.

622.51 Primary Lithium (Non-Rechargeable) Cells and Batteries

Small consumer-type primary lithium cells or batteries (lithium metal or lithium alloy) like those used to power cameras and flashlights are mailable in a single shipment with the following restrictions:

  1. The batteries must be installed in the equipment being shipped.
  2. Each shipment may contain a maximum of four lithium cells or two lithium batteries.
  3. The lithium content must not exceed 1 gram (g) per cell.
  4. The total aggregate lithium content must not exceed 2 g per battery.
  5. The batteries installed in the equipment must be protected from damage and short circuit.
  6. The equipment must be equipped with an effective means of preventing it from being turned on or activated.
  7. The equipment must be contained in a strong sealed package and cushioned to prevent movement or damage.
622.52 Secondary Lithium-ion (Rechargeable) Cells and Batteries

Small consumer-type lithium-ion cells and batteries like those used to power cell phones and laptop computers are mailable in a single shipment with the following restrictions:

  1. The batteries must be installed in the equipment being shipped.
  2. Each shipment may contain a maximum of four lithium-ion cells or two lithium-ion batteries.
  3. The lithium content must not exceed 20 Watt-hour rating (Wh) per cell.
  4. The total aggregate lithium content must not exceed 100 Wh per battery.
  5. Each battery must bear the “Watt-hour” or “Wh” marking on the battery to determine if it is within the limits defined in items c and d.
  6. The batteries installed in the equipment must be protected from damage and short circuit.
  7. The equipment must be equipped with an effective means of preventing it from being turned on or activated.
  8. The equipment must be contained in a strong sealed package and cushioned to prevent movement or damage.