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Interpretation Response #21-0045

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

Interpretation Response Details

Response Publish Date:

Company Name: Milport Enterprises, Inc.

Individual Name: Tom Grego

Location State: WI Country: US

View the Interpretation Document

Response text:

June 22, 2021

Mr. Tom Grego
Technical Director
Milport Enterprises, Inc.
2829 South 5th Court
Milwaukee, WI  53207

Reference No. 21-0045

Dear Mr. Grego:

This is in response to your April 22, 2021, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the packaging requirements for "UN2672, Ammonia solution, 8, PG III." Specifically, you seek clarification on the applicability of special provision 336, which is listed in Column 7 of the § 172.101 Hazardous Materials Table (HMT) for this material.

In your letter, you state that your company received a citation for transporting the above hazardous material in a packaging meeting the requirements of §§ 173.24(g) and 173.24a(b)(4), but not in a packaging described in special provision 336. It is your understanding that special provision 336 was added to the HMR in a final rule published on March 18, 2014 [79 FR 15033] under Docket No. PHMSA-2011-0158 (HM-233C), which adopted the terms of Special Permit (SP) DOT-SP 11836 as an alternative packaging method than what is required in §§ 173.24(g) and 173.24a(b)(4). You seek confirmation that it was not the Pipeline and Hazardous Materials Safety Administration's (PHMSA) intent to require the operational controls in special provision 336 to apply to packagings meeting the requirements of §§ 173.24(g) and 173.24a(b)(4).

Your understanding is correct. In the HM-233C final rule, PHMSA adopted DOT-SP 11836 as new special provision 336. As stated in the HM-233C final rule, "DOT-SP 11836 authorizes the transportation of specific ammonia solutions in specification UNIH1 drums, UN3H1 jerricans, and UN6HA1 composite packagings that do not meet the provisions in §§ 173.24(g) and 173.24a(b)(4). Specific operational controls are required in lieu of compliance with these two requirements."

Therefore, packagings for specific ammonia solutions such as "UN2672, Ammonia solution, 8, PG III" that meet the provisions of §§ 173.24(g) and 173.24a(b)(4) are not required to meet the operational controls of special provision 336.

I hope this information is helpful. Please contact us if we can be of further assistance.


T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

172.101, 173.24(g), 173.24a(b)(4)

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
173.24a Additional general requirements for non-bulk packagings and packages