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325 DOT Hazardous Materials Warning Labels

325.1 Nonmailable Warning Labels

In commerce, packages containing hazardous materials (except those qualifying as ORM–D material or a limited quantity shipment) must display the appropriate DOT diamond–shaped hazardous materials warning label. Any mailpiece bearing, or required under 49 CFR to bear, one of the warning labels shown in Exhibit 325.1 is prohibited from mailing.

(The labels shown in the exhibits are not shown to size. DOT warning labels must meet the size and color requirements in 49 CFR 172.407 through 172.446.)

Exhibit 325.1 

DOT Hazardous Materials Warning Labels: PROHIBITED IN THE MAIL

Exhibit 325.1, DOT Hazardous Materials Warning Labels: PROHIBITED IN THE MAIL

325.2 Mailable Warning Labels

The warning labels shown in Exhibit 325.2a and Exhibit 325.2b and
Exhibit 325.3 may appear only on mailpieces containing mailable hazardous materials that require use of the label under Postal Service requirements.

Exhibit 325.2a

DOT Hazardous Materials Warning Labels: PERMITTED ON MAILABLE HAZARDOUS MATERIALS

Exhibit 325.2a, DOT Hazardous Materials Warning Labels: PERMITTED ON MAILABLE HAZARDOUS MATERIALS

Exhibit 325.2b

DOT Hazardous Material Warning Labels: PERMITTED FOR MAILABLE LIMITED QUANTITIES ONLY

Exhibit 325.2b, DOT Hazardous Material Warning Labels: PERMITTED FOR MAILABLE LIMITED QUANTITIES ONLY

325.3 Limited Quantity Square-on-point Labels

Unless otherwise noted, each mailpiece containing a mailable hazardous material must be plainly and durably marked on the address side with the required shipping name and UN identification number. Mailpieces containing mailable air-eligible hazardous materials intended for air transportation must bear a DOT limited quantity square-on-point marking under Exhibit 325.3. Mailpieces containing mailable hazardous materials intended for surface transportation may be entered and optionally marked under the ORM-D category until January 1, 2021. After this date, all parcels containing mailable hazardous materials must bear the appropriate DOT square-on-point marking and other associated markings when required. The following also applies:

  1. The use of DOT limited quantity square-on-point markings are required for mailpieces intended for air transportation and optional for mailpieces intended for surface transportation. The plain square-on-point marking is used for shipments sent by surface transportation, and the square-on-point marking including the symbol “Y” superimposed in the center is used for shipments sent by air transportation. The following also applies:
    1. Markings must be durable, legible, and readily visible.
    2. The marking must be applied on at least one side or one end of the outer packaging. The border forming the square-on-point must be at least 2 mm (0.08 inch) in width and the minimum dimension of each side must be 100 mm (3.94 inches), unless the package size requires a reduced size marking of no less than 50 mm (1.97 inches) on each side.
    3. For surface transportation, the top and bottom portions of the square-on-point and the border forming the square-on-point must be black and the center must be white or of a suitable contrasting background. Surface shipments containing qualifying ORM-D materials and bearing the square-on-point limited quantity marking are not required to be marked with the shipping name and identification number.
    4. For transportation by aircraft, the top and bottom portions of the square-on-point and the border forming the square-on-point must be black and the center must be white or of a suitable contrasting background. The symbol ‘‘Y’’ must be black and located in the center of the square-on-point and be clearly visible. Mailpieces intended for transport by air must also be marked with the proper shipping name, identification number, and must also display the appropriate DOT hazardous material warning label (only when required for the hazard class shipped) in accordance with this publication.
  2. The UN identification number is not required on mailpieces containing ORM-D materials and intended for surface transportation. A mailable ORM-D material must be marked on the address side with “ORM-D” (or marked under 325.3a.) immediately following, or below the proper shipping name. The proper shipping name for a mailable ORM-D material is “consumer commodity.” The designation “ORM-D” must be placed within a rectangle that is approximately 6.3 mm (1/4 inch) larger on each side than the applicable designation. Mailpieces containing ORM-D materials sent as Standard Mail, Standard Post, Parcel Select, or Package Services must also be marked on the address side as “Surface Only” or “Surface Mail Only.”

Exhibit 325.3 

DOT Hazardous Material Warning Labels: PERMITTED FOR LIMITED QUANTITY SQUARE-ON-POINT

Exhibit 325.3 DOT Hazardous Material Warning Labels: PERMITTED FOR LIMITED QUANTITY SQUARE-ON-POINT