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Interpretation Response #15-0211 ([Integrated Surface Technologies] [Dr. Jeffrey Chinn])

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

Interpretation Response Details

Response Publish Date:

Company Name: Integrated Surface Technologies

Individual Name: Dr. Jeffrey Chinn

Location State: CA Country: US

View the Interpretation Document

Response text:

May 9, 2016

Dr. Jeffrey Chinn
Chief Technical Officer
Integrated Surface Technologies
1455 Adams Dr., Suite 1125
Menlo Park, CA 94025

Reference No. 15-0211

Dear Dr. Chinn:

This responds to your October 27, 2015 email in which you request clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically you ask if a DOT-SP 7737-1800 aluminum cylinder may be used as an inner packaging with a 4GV outer packaging for “UN2986, Chlorosilanes, Corrosive, Flammable, n.o.s.” You state that the chlorosilanes can be corrosive to steel, and aluminum has better chemical compatibility for your application.

49 CFR 173.206 authorizes the use of combination packagings with steel or glass inner receptacles for materials described as “UN2986, Chlorosilanes, Corrosive, Flammable, n.o.s.” Section 173.206(c) authorizes certain single packagings for these materials except for transportation by passenger aircraft. For PG I liquids, specification or UN standard cylinders, except Specification 3HT and those prescribed for acetylene, are authorized. For PG II liquids, specification cylinders, except Specification 8 and 3HT cylinders, are authorized.

Even though the HMR specifies certain packagings, it is the responsibility of the person offering the hazardous material for transportation to ensure that such packagings are compatible with their lading. This particularly applies to corrosivity, permeability, softening, premature aging and embrittlement. Further, packaging materials and contents must be such that there will be no significant chemical or galvanic reaction between the materials and the contents of the package. See § 173.24(e).

DOT-SP 7737-1800 aluminum alloy cylinders are authorized for the transportation of any Division 2.1, 2.2, and 2.3, and Class 3 material for which DOT specification 3AL cylinders is prescribed or authorized in 49 CFR Part 173. See section 6 of the special permit. As such, UN2986, Chlorosilanes, Corrosive, Flammable, n.o.s., may not be offered for transportation or transported in a DOT-SP 7737-1800 aluminum cylinder as an inner packaging of a combination packaging or as a single packaging.

You may apply to PHMSA for permission to use the non-DOT specification packaging described in your request under the terms of a special permit. To apply, you must submit an application to the Associate Administrator for Hazardous Materials Safety in conformance with the requirements prescribed in 49 CFR Part 107, Subpart B. In your application, you must provide justification that the packaging design you are considering achieves a level of safety that is equal to or greater than that required under the HMR. You may obtain information on the special permit application process from our website at, or by calling PHMSA's Approvals and Permits Division at (202) 366-4511.

I hope this satisfies your inquiry. Please feel free to contact us if you need further assistance.



Duane A. Pfund
International Standards Coordinator
Standards and Rulemaking Division

173.206, 173.206(c), 173.24(e), 107

Regulation Sections

Section Subject
173.206 Packaging requirements for chlorosilanes
173.24 General requirements for packagings and packages