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Mercury Remains Prohibited in The Mail

WASHINGTON — The Postal Service is reminding customers that metallic mercury and devices containing metallic mercury are always prohibited in the mail stream. This includes antique items such as thermometers, barometers, blood pressure monitors, switches and relays. However, compact fluorescent lamps, which contain small amounts of mercury in vapor form, are mailable domestically but not internationally (including APO/FPO/DPO destinations).

If a person knowingly mails items or materials that are dangerous or injurious to life, health, or property, they may face a CIVIL PENALTY of at least $250, but not more than $100,000 per violation; the costs of any cleanup associated with each violation, and damages. They may also face criminal penalties.

The Postal Service is committed to the safety and security of its employees, its customers, and its transportation networks and will remain vigilant in safeguarding the mail stream against any article that might pose a hazard to health, safety, property, or the environment.

The Postal Service offers FAQs on prohibited items containing mercury and the Postal Inspection Service has released a public service announcement on mercury in the mail. Additionally, please see the chart below regarding information on commonly encountered mercury.

Commonly Encountered Mercury

United States Mercury Remains Prohibited in The Mail.
Visual Description of Item Mailability of Item
Liquid mercury Liquid mercury — Often encountered in a wide range of volumes. Reasons for sending include uses for gold reclamation/refinement, preparation of dental amalgams, and element collections. Domestic Ground – Prohibited
Domestic Air – Prohibited
International – Prohibited

Prohibited as per Section 348.21e

Mercury barometer Mercury barometer — These devices often contain significant amounts of mercury that are not well contained.  They have been responsible for several leaks.
(Note: Fully digital versions are mailable without restrictions.)
Domestic Ground – Prohibited
Domestic Air – Prohibited
International – Prohibited

Prohibited as per Section 348.21e

Mercury thermometer Mercury thermometer — These items may contain significant amounts of mercury in breakable containment (glass).

[Modern versions (i.e. digital and those using red liquid, which is alcohol to which red coloring has been added) are mailable without restrictions.]

Domestic Ground – Prohibited
Domestic Air – Prohibited
International – Prohibited

Prohibited as per Section 348.21e.

Mercury sphygmomanometer Mercury sphygmomanometer (blood pressure gauge) — These devices may contain significant amounts of mercury in breakable containment (glass).

(Note: Fully digital versions are mailable without restrictions.)

Domestic Ground – Prohibited
Domestic Air – Prohibited
International – Prohibited

Prohibited as per Section 348.21e.

Mercury switch Mercury switch — May exist in a small enough size to get below the 100 mg. limit; however, this would be the exception rather than the rule. If you can see the mercury, it is not mailable. Domestic Ground – Prohibited
Domestic Air – Prohibited
International – Prohibited

Prohibited as per Section 348.21e, may encounter some that adhere to Section 348.22g.

Mercury relay Mercury relay — May exist in a small enough size to get below the 100 mg. limit; however, this would be the exception rather than the rule. If you can see the mercury, it is not mailable. Domestic Ground – Prohibited
Domestic Air – Prohibited
International – Prohibited

Prohibited as per Section 348.21e, may encounter some that adhere to Section 348.22g.

Compact fluorescent lamps Compact fluorescent lamps — These items contain small amounts of mercury vapor. If broken, there will be no visible mercury and the vapors will readily disperse. Domestic Ground – Mailable
Domestic Air – Mailable
International – Prohibited

Mailable as per Section 348.22g.
See also Packaging Instruction 8C.

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