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Interpretation Response #08-0197 ([Silver/Cims LLC] [Mr. Jim Silver])

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

Interpretation Response Details

Response Publish Date:

Company Name: Silver/Cims LLC

Individual Name: Mr. Jim Silver

Location State: TX Country: US

View the Interpretation Document

Response text:

November 20, 2008

Mr. Jim Silver

Silver/Cims LLC

1304 First Street

Seabrook, TX 77586

Ref. No. 08-0197

Dear Mr. Silver:

This is in response to your electronic transmission requesting clarification of the Hazardous Materials Regulations (HMR: 49 CFR Parts 171-180) regarding the import of Dimethyl sulphate or Dimethyl sulfate, UN1595, 6.1, 8, PG I, Hazard Zone B in a UN portable tank that was manufactured outside the United States. You state that the portable tank is manufactured to the ASME Code, Section VIII, but is not "U" stamped. You ask whether the shipment, which is being transported in accordance with the International Maritime Dangerous Goods (IMDG) Code, may be imported into the United States without the "U" stamp.

The answer is no. A UN portable tank used to import Dimethyl sulfate, UN1595, 6.1, 8, PG I, Hazard Zone B into the United States is required to be certified and stamped to the ASME Code as specified in §§ 171.23(b)(10)(ii), 173.244, 178.273(b)(6) and 178.274(b)(1). The U.S. Department of Transportation requires the shipment of toxic-inhalation-hazard liquids to be transported in ASME Code "U" stamped portable tanks regardless of what other regulatory standards may allow. The "U" stamp can only be applied at the time of manufacture and is the only recognized form of certification that verifies the ASME quality system has been properly implemented. Additionally, the UN portable tank must conform to any applicable special provisions, such as Codes TP 38 and TP 45, listed in Column 7 of the § 172.101 Hazardous Materials Table.

I hope this information is helpful. Please contact this office should you have additional questions.



Hattie L. Mitchell

Chief, Regulatory Review and Reinvention

Office of Hazardous Materials Standards

171.23(b)(10)(ii), 174.244, 178.273(b)(6) & 178.274(b)(1)

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