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Interpretation Response #02-0056 ([Allied Universal Corp.] [Robin J. Eddy])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Allied Universal Corp.

Individual Name: Robin J. Eddy

Location State: FL Country: US

View the Interpretation Document

Response text:

Dec 23, 2002

Mr. Robin J. Eddy                 Reference No. 02-0056
Safety and Regulatory Compliance Manager
Allied Universal Corp.
3901 NW 115th Avenue

Miami, Florida 33178

Dear Mr. Eddy:

This responds to your letter concerning our previous interpretation dated October 11, 2001 to the Chlorine Institute regarding the requirements for placarding materials poisonous by inhalation under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).  You asked for further clarification of the requirements applicable to dual placarding of Chlorine and Sulfur dioxide rail cars shipped to the United States from Canada or Mexico.  We apologize for the delay in responding and hope it has not caused any inconvenience.  Your questions are paraphrased and answered as follows:

Q1. Your company receives rail cars from Canada containing "Chlorine" classed as a Division 2.3 (Poison gas).  The Canadian rail car displays the international "TOXIC GAS"; placard with the identification number "UN 1017" displayed across the middle, and the United States I "POISON GAS" placard is displayed containing the words "INHALATION HAZARD." You asked, should the United States "POISON GAS" placard display the identification number "UN 1017" instead of the text "INHALATION HAZARD" on the placard.

A1. A Canadian rail car containing Chlorine transported to the United States from Canada must be placarded with the POISON GAS placard specified in § 172.504(e), Table 1, and as shown in § 172.540. Except for a RADIOACTIVE or DANGEROUS placard, text indicating a hazard, such as "INHALATION HAZARD", is not required on a placard (see § 172.519(b)(3)). The rail car must be marked "Inhalation Hazard" on two opposing sides of a bulk packaging as specified in § 172.313(a). When the words "INHALATION HAZARD" appear on the placard, the marking is not required on the package.

The identification number "UN 1017" must be marked on each side and each end of a rail car as prescribed in §172.330. In accordance with § 172.332, an identification number may be displayed on a placard, orange panel, or white square-on-point configuration.  Display of the Canadian "TOXIC GAS" placard is not prohibited, and may be used to display the identification number "UN 1017" for Chlorine.

Q2. Rail car shipments of "Sulfur dioxide" from Mexico only display the international "TOXIC GAS" placard.  May rail car shipments of Sulfur dioxide from Mexico display dual placards?

A2. In accordance with § 171.12(e), hazardous materials shipments from Mexico to the United States or from the United States to Mexico must conform to all of the applicable requirements of the HMR.  When a rail car contains a material poisonous by inhalation, such as Sulfur dioxide, transported from Mexico to the United States, the rail car must be placarded with the "POISON GAS" placard as shown in § 172.540. Display of the international "TOXIC GAS" placard is not prohibited, as specified in § 172.502(b).

I hope this satisfies your inquiry.  If we can be of further assistance, please contact us.


Delmer F. Billings
Chief, Standards Development
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
172.505 Placarding for subsidiary hazards