USPS Packaging Instruction 8A

Corrosives

A corrosive is any liquid or solid that causes visible destruction or irreversible alteration in human skin tissue at the site of contact or a liquid that has a severe corrosion rate on steel or aluminum.

A Class 8 corrosive material that qualifies as a Limited Quantity air or Limited Quantity surface material is permitted via air or surface transportation in domestic mail provided that all applicable requirements in 348 are met.

Proper Shipping Name

• Various (refer to Appendix A).

ID Number

• Various (refer to Appendix A).

Mailability

• International Mail: Prohibited.
• Domestic Mail: Permitted via air or surface transportation when packaging requirements are met.

Required Packaging

Separate packaging requirements apply for liquids and solids.

For Mailable Liquid Corrosives:

General

• Liquid Corrosive. A liquid mixture must be 1 pint (16 ounces) or less, and must contain 15 percent or less corrosive material with the remainder of the mixture not being a hazardous material, unless otherwise specified for a specific corrosive material.

Primary Receptacles

• Primary receptacles must be securely sealed.
• The primary receptacle must be tightly sealed with a screw cap having a minimum of one–and–one–half turns, a soldering clip, or other means to effect secure closure. A friction–top closure is not acceptable.
• Volume per primary receptacle is limited to 16 ounces.
• Multiple primary receptacles are permitted.

Absorbent and Cushioning Material

• A noncombustible absorbent material that is capable of taking up all liquid in case of leakage must surround the primary receptacle.
• Cushioning material must surround the primary receptacle to prevent breakage.

Secondary Packaging

• The secondary packaging must be compatible with the design of the primary receptacle.
• The secondary packaging must be tightly sealed with a screw cap having a minimum of one–and–one–half turns, a soldering clip, or other means to effect secure closure. A friction–top closure is not acceptable.

Outer Packaging

• The primary receptacle, absorbent material, cushioning material, and secondary packaging must be packed in a strong outer packaging. Refer to 339.4.
• Each mailpiece must not exceed a total weight of 25 pounds.

Marking

Labels and markings must be placed on the address side of the mailpiece unless specified differently in 221.1 and 325.1.

• For air transportation, mailpieces must bear the DOT Limited Quantity air mark (with the symbol “Y” in the center), an approved DOT Class 8 hazardous material warning label, the identification number and the proper shipping name.
• For surface transportation, the outer packaging must bear an approved DOT Limited Quantity surface mark designating surface transportation, prepared under 348.4(b).
• A complete return and delivery address must be used.

Documentation

• For air transportation, a properly completed Shipper‘s Declaration for Dangerous Goods must be prepared in triplicate and affixed to the outside of the mailpiece.

For Mailable Solid Corrosives:

General

• A solid mixture must be 10 pounds or less per primary receptacle and must contain 10 percent or less corrosive material with the remainder of the mixture not being a hazardous material, unless otherwise specified for a specific corrosive solid.

Primary Receptacle

• Each primary receptacle must be sift-proof and be securely sealed.

Secondary Packaging

• Each primary receptacle must be packed within a sift-proof secondary packaging that is compatible with the primary receptacle.

Outer Packaging

• A strong outer packaging that is capable of firmly and securely holding the primary receptacle(s) and cushioning material is required. Refer to 339.4.
• Multiple primary receptacles and compatible secondary packaging may be packed within a single outer packaging up to a total weight of 25 pounds per mailpiece.

Marking

Labels and markings must be placed on the address side of the mailpiece unless specified differently in 221.1 and 325.1.

• For air transportation, mailpieces must bear the DOT Limited Quantity air mark (with the symbol “Y” in the center), an approved DOT Class 8 hazardous material warning label, the identification number, and the proper shipping name
• For surface transportation, the outer packaging must bear an approved DOT Limited Quantity surface mark designating surface transportation, prepared under 348.4(b).
• A complete return and delivery address must be used.

Documentation

• For air transportation, a properly completed Shipper‘s Declaration for Dangerous Goods must be prepared in triplicate and affixed to the outside of the mailpiece.