Hazardous Shipping 101 with USPS

An in-depth guide to effectively and safely ship hazardous materials through USPS
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Last update:

June 30, 2023

The United States Postal Service (USPS) is pivotal in connecting individuals and businesses by delivering mail and packages nationwide and beyond.

However, with the shipment of various goods, the responsibility of ensuring safety and compliance with regulations comes. One crucial aspect of this responsibility is the handling and shipping hazardous materials.

This article provides an essential guide on what to know when navigating hazardous shipping with USPS.

Understanding Hazardous Materials

Hazardous materials can pose a risk to health, safety, property, or the environment.

They can be in the form of chemicals, gases, flammable liquids, explosives, or radioactive materials. When shipping these materials, it is crucial to understand the risks they pose and how to manage them safely and compliantly.

USPS Regulations on Hazardous Materials

USPS has its guidelines called Publication 52, Hazardous, Restricted, and Perishable Mail, which outlines the requirements for shipping hazardous materials through USPS.

In addition to complying with U.S. law and U.S. Postal Service hazardous materials guidelines, the sender should also ship items securely with required labels and markings.

For more detailed documentation, you can find what USPS classifies as hazardous materials.

What Can and Can’t be Shipped

Hazardous materials include batteries, dry ice, flammable liquids, aerosol sprays, airbags, ammunition, fireworks, gasoline, lighters, lithium batteries, matches, nail polish, paint, perfume, thermometers and more.

But USPS permits the shipping of certain hazardous materials but under strict conditions. On the other hand, explosives, radioactive materials, and certain types of chemicals are generally not permitted.

For example, the 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 and similar devices. However, compact fluorescent lamps, which contain small amounts of mercury in vapor form, are mailable domestically but not internationally.

A guide on making Hazardous Material shipping safer can be found in the HAZMAT Shipping Safety Guide | USPS Delivers.

Packaging Requirements

Proper packaging is crucial in minimizing risks. USPS requires that hazardous materials be packed in sturdy, leak-proof containers.

Additionally, the packaging must be labeled clearly with the appropriate hazard class symbols and any other relevant information. For more tips on packing hazardous materials, you can use the HAZMAT search tool on the USPS website.

Consequences of Non-compliance

Failure to comply with USPS and federal regulations for shipping hazardous materials can result in severe penalties, including fines and imprisonment.

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.

International Shipping of Hazardous Materials with USPS

The United States Postal Service (USPS) also facilitates international shipping, so understanding the protocols and regulations for shipping hazardous materials is imperative.

Compliance with International Regulations

Compliance with international regulations is critical when shipping hazardous materials internationally through USPS.

This includes adherence to the International Air Transport Association (IATA) guidelines. The IATA Dangerous Goods Regulations (DGR) guide is essential as it is widely recognized and utilized for international air transport of hazardous materials.

Customs and Import Restrictions

Each country has its own customs regulations, and restrictions regarding the importation of hazardous materials.

Before shipping internationally, it’s essential to check the destination country’s customs requirements and ensure that the items being shipped are permitted. Failure to do so may result in the confiscation of the shipment or fines.

Proper Documentation

International shipping often requires additional documentation compared to domestic shipping.

This includes customs forms and detailed descriptions and declarations of the contents in the case of hazardous materials. This information should be accurate and complete to avoid delays or other issues with customs.

Packaging and Labeling for International Shipments

In addition to the packaging requirements of USPS, international shipments may need to comply with specific international packaging standards.

USPS has specific International Mail Manuals (IMM) that provide mailing conditions for each country, including restrictions on hazardous materials.

It’s important to consult the IMM for the destination country to understand the specific mailing conditions and ensure compliance.


Shipping hazardous materials through USPS is a responsibility that should be handled with utmost care and adherence to regulations.

By understanding the types of materials that can be shipped and ensuring proper packaging, individuals and businesses can mitigate risks and contribute to the safe handling and transportation of hazardous materials. 

Furthermore, compliance with international regulations, proper documentation, and understanding of customs restrictions are essential when it comes to international shipping.

Written on:

June 20, 2023
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