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Postal Explorer > Publication 52 - Hazardous, Restricted, and Perishable Mail > 4 Restricted Matter > 45 Liquids, Powders, and Odor–Producing Materials

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45 Liquids, Powders, and Odor–Producing Materials

451 Definitions

A liquid is any substance that flows readily and assumes the form of the container, but retains an independent volume. For the purposes of mailability, a liquid may be a cream or paste or any other nonhazardous substance (except a gas) that may liquefy under existing conditions.

A powder is a substance composed of finely dispersed solid particles.




Link to "444 Nonmailable Knives in the Mails"Link to contents for "4 Restricted Matter"      Link to IndexLink to "452 Mailability"