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623 Nonmailable Hazardous Materials

The following types of hazardous materials, as defined in chapter 3, DMM 601.10, and IMM 135–136, are prohibited in international mail:

  1. Class 1, explosives (including explosive devices) (341 and DMM 601.10.11).
  2. Class 2, gases (342 and DMM 601.10.12).
  3. Class 3, flammable and combustible liquids (343 and DMM 601.10.13).
  4. Class 4, flammable solids including matches (344 and DMM 601.10.14).
  5. Class 5, oxidizing substances and organic peroxides (345 and DMM 601.10.15).
  6. Class 6, Division 6.1, toxic substances (including irritants) (346 and DMM 601.10.16).
  7. Class 6, Division 6.2, infectious substances (346 and DMM 601.10.17), except as permitted in 622.2.
  8. Class 7, radioactive materials (347 and DMM 601.10.18), except as permitted in 622.3).
  9. Class 8, corrosives (348 and DMM 601.10.19).
  10. Class 9, miscellaneous hazardous materials (349 and DMM 601.10.20).
  11. Dry ice (carbon dioxide solid) (349.23 and DMM 601.10.20.4).
  12. Magnetized materials capable of causing a compass deviation at a distance of 7 feet or more (349.24 and DMM 601.10.21). See 122.4 for mailable magnetized materials.
  13. ORM–D materials (335 and 121.3).