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Interpretation Response #11-0199 ([Trimac Management Services] [Mr. Len Comtois])

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

Interpretation Response Details

Response Publish Date:

Company Name: Trimac Management Services

Individual Name: Mr. Len Comtois

Country: CA

View the Interpretation Document

Response text:

May 30, 2012



Mr. Len Comtois
Director HSSE and Regulatory Compliance
Trimac Management Services
151 Reverchon Ave. Suite 200
Point-Claite, Quebec, Canada
H9P 1K1

Ref. No.: 11-0199

Dear Mr. Comtois:

This responds to your letter dated August 18, 2011, requesting guidance on the shipping description for anhydrous ammonia shipped in a cargo tank from Canada to the United States in accordance with the Transport Dangerous Goods (TDG) Regulations and the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). In your letter, you state that the third paragraph of a July 29, 2008 letter (08-0059) incorrectly infers that the shipping paper used for the transport of anhydrous ammonia from Canada to the United States must adhere to the provisions of § 172.102, Special Provision 13. You believe that since a shipment of anhydrous ammonia from Canada to the United States is an international shipment, the shipping papers must utilize the shipping description "RQ, UN1005, Ammonia, Anhydrous, 2.3, (8), Toxic Inhalation Hazard Zone D" appropriate for describing materials in international transportation. You add that the HMR assign Special Provision 4 to this description.

The appropriate shipping description for a cargo tank of anhydrous ammonia transported from Canada to the United States as described in your letter is "RQ, UN1005, Ammonia, Anhydrous, 2.3, (8), Toxic Inhalation Hazard Zone D." Special Provision 13 found in § 172.102 applies when using the shipping description "UN1005, Ammonia, anhydrous, 2.2" appropriate for domestic transportation. Special Provision 4 is assigned to the § 172.101 entry appropriate for international transportation and requires the material to be described as a Toxic Inhalation Hazard, Zone D. In accordance with § 171.22(b), anhydrous ammonia offered for transportation or transported in conformance with the TDG regulations must also conform to all applicable requirements of Subpart C of Part 171 of the HMR.

I hope this information is helpful. If you have further questions, please do not hesitate to contact this office.



Ben Supko
Senior Regulations Officer
Standards and Rulemaking Division

172.101, 172.102 SP 13, 171.22

Regulation Sections

Section Subject
171.22 Authorization and conditions for the use of international standards and regulations
172.101 Purpose and use of hazardous materials table