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Interpretation Response #16-0100 ([Potash Corp.] [Mr. Tracey Smith])

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

Interpretation Response Details

Response Publish Date:

Company Name: Potash Corp.

Individual Name: Mr. Tracey Smith

Location State: IL Country: US

View the Interpretation Document

Response text:

September 19, 2016

Tracey G. Smith
Manager, Regulatory Compliance
1101 Skokie Blvd., Ste 400
Northbrook, IL 60062

Ref. No. 16-0100

Dear Mr. Smith:

This responds to your June 7, 2016 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to anhydrous ammonia being regulated as a marine pollutant.  Your questions are paraphrased and answered as follows:

Q1. What does the “(I)” located behind “Ammonia, anhydrous” in Appendix B of the § 172.101 Hazardous Materials Table indicate?

A1. It indicates that a hazardous material that has been classified under the international entry, “UN 1005, Ammonia, anhydrous, 2.3” is regulated as a marine pollutant if it also meets the definition of a marine pollutant in § 171.8.

Q2. Why is “Ammonia, anhydrous” transported under the domestic entry not listed as a marine pollutant under Appendix B of the HMT while “Ammonia solutions” is regulated as a marine pollutant domestically?

A2. A final rule published on January 8, 2014 [(HM-215M); 80 FR 1075] revised Appendix B to § 172.101 by adding sixty-two new entries to the List of Marine Pollutants to harmonize with the International Maritime Dangerous Goods (IMDG) Code.  However, we chose not to impose new requirements on the transportation of “ammonia, anhydrous” domestically because of the authorized classification as Division 2.2 for domestic transportation.

I trust this satisfies your inquiry.  Please contact us if we can be of further assistance.


Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

172.101, 171.8


Regulation Sections

Section Subject
171.8 Definitions and abbreviations
172.101 Purpose and use of hazardous materials table