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2 General Guidelines

21 Mailability

211 General

Under 18 U.S.C. 1716, all matter that is outwardly or of its own force dangerous or injurious to life, health, or property is nonmailable. The knowing deposit of such matter in the mail is a crime punishable by fine, imprisonment, and/or other penalty.

For reasons of safety, most hazardous materials are nonmailable. However, some hazardous materials and otherwise restricted matter, or perishable matter are permitted to be mailed when the requirements in
DMM 601.8–11 and the supplemental criteria in this publication are fully met.

DMM 601.10 and chapter 3, Appendix A, and Appendix C of this publication provide detailed information about hazardous materials that are permitted to be mailed and the conditions that apply.

DMM 601.12 and 601.9 and chapters 4 and 5 of this publication provide information about restricted matter and perishable matter that either is nonmailable or that may be mailable under specified conditions, as applicable.

Chapter 6 specifies the mailing conditions that apply to hazardous materials, restricted matter, and perishable matter in international mail, including hazardous materials for delivery to overseas military post office (APO/FPO) addresses.

Chapter 7 contains information regarding mailability of hazardous materials, restricted matter, and perishable matter in domestic mail via air transportation.