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Interpretation Response #17-0046

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

Interpretation Response Details

Response Publish Date:

Company Name: TT Club

Individual Name: Mr. Michael Yarwood

Location State: EC3M 4ST Country: GB

View the Interpretation Document

Response text:

August 28, 2017
Michael Yarwood
Claims Executive
TT Club
90 Fenchurch Street
London  EC3M 4ST
Reference No. 17-0046
Dear Mr. Yarwood:
This letter is in response to your April 3, 2017, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the transport of phosphorous oxychloride and phosphorous trichloride in United Nations (UN) portable tanks.  The hazardous materials are transported from Europe to the United States in UN portable tanks in accordance with the International Maritime Dangerous Goods Code.  Specifically, you ask whether these UN portable tanks must be marked with a “U” stamp.  
A UN portable tank used to import “UN1810, Phosphorus oxychloride, 6.1, (8), PG I, Toxic Inhalation Hazard Zone B” and “UN1809, Phosphorus trichloride, 6.1, (8), PG I, Toxic Inhalation Hazard Zone B” into the United States must be designed and constructed in accordance with the requirements in Section VIII, Division I of the American Society of Mechanical Engineers (ASME) Code.  Additionally, portable tanks must have an ASME certification and a “U” stamp when used for Hazard Zone A or B toxic by inhalation liquids as required by § 178.274(b)(1).  The U.S. Department of Transportation requires Zone A or B toxic by inhalation liquids to be transported in ASME Code “U” stamped portable tanks regardless of what other regulatory standards may allow.  Other design codes may be used if approved by the Associate Administrator.
In your email, you reference a letter of interpretation previously issued under Reference No. 13‑0151 that authorizes in the United States the use of a UN standard packaging, including a UN portable tank, manufactured outside of the United States in conformance with national or international regulations based on the UN Recommendations on the Transport of Dangerous Goods.  This response remains correct for hazardous materials that are not toxic by inhalation.  However, the response in 13-0151 is not applicable to materials toxic by inhalation or the
situation described in your email.  Specifically, § 171.23(b)(10)(ii) requires a material toxic by inhalation to be packaged in accordance with the requirements of this subchapter.  As such, all relevant requirements in the HMR apply including §§ 173.244, 178.273(b)(6), and 178.274(b)(1). 
I hope this information is helpful.  Please contact us if we can be of further assistance.
Duane Pfund
International Standards Coordinator
Standards and Rulemaking Division
178.274(b)(1), 171.23(b)(10)(ii), 173.244, 178.273(b)(6),

Regulation Sections

Section Subject
171.23 Requirements for specific materials and packagings transported under the ICAO Technical Instructions, IMDG Code, Transport Canada TDG Regulations, or the IAEA Regulations
173.244 Bulk packaging for certain pyrophoric liquids (Division 4.2), dangerous when wet (Division 4.3) materials, and poisonous liquids with inhalation hazards (Division 6.1).
178.273 Approval of Specification UN portable tanks
178.274 Specifications for UN portable tanks