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Interpretation Response #14-0039 ([ARC Process, Inc.] [Mr. Steve M. Reed])

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

Interpretation Response Details

Response Publish Date:

Company Name: ARC Process, Inc.

Individual Name: Mr. Steve M. Reed

Location State: TX Country: US

View the Interpretation Document

Response text:

August 21, 2014

Mr. Steve M. Reed
ARC Process, Inc.
3921 Steck Avenue, Suite A-120
Austin, Texas 78759

Ref. No. 14-0039

Dear Mr. Reed:

This responds to your initial March 5, 2014 email request, your April 17, 2014 email request, and follow-up telephone conversation and email correspondence with a member of our staff seeking clarification on the non-bulk packaging requirements for pyrophoric materials and the manufacturing of DOT Specification 4B cylinders with bolted tops under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask about authorized inner packaging for transporting high purity metal organic materials used in the chemical and semi-conductor industries. These high purity metal organic materials are classified as a hazardous material and described as "UN 3394, Organometallic substance, liquid, pyrophoric, water-reactive, 4.2 (4.3), PG I." Your questions are paraphrased and answered below.

Q1. For liquid pyrophoric materials, do the HMR prohibit openings on inner packagings from exceeding one inch diameter?

A1. The answer to your question is yes. The final rule HM-215L [78 FR 987], issued January 7, 2013, removed subparagraphs (1), (2), and (3) from § 173.181(c) which sets forth the non-bulk packaging requirements for pyrophoric materials (liquid). Prior to publication of HM-215L, § 173.181(c)(1) stated "inner packagings must have no opening exceeding 25 mm (1 inch) diameter." We intended to only revise the introductory paragraph (c), with paragraphs (1), (2), and (3) of § 173.181(c) remaining unchanged. However, an incorrect amendatory instruction led to the deletion of paragraphs (c)(1) through (3). The deleted text will be reinstated in a future rulemaking. It is our intent that individuals packaging and offering these materials continue to offer shipments of liquid pyrophoric materials in compliance with the requirements of § 173.181 (c)(1) through (3) effective prior to publication of HM-215L.

Q2. Do the HMR authorize the modification of 4B cylinders by drilling holes in the cylinder tops to receive valve protection rings instead of welding valve protection rings to the cylinder tops?

A2. The answer to your question is no. Section 178.50 provides the specifications for 4B welded and brazed steel cylinders. Paragraph (e) of this section states that only the attachment of neckrings, footrings, handles, bosses, pads, and valve protection rings to the tops and bottoms of cylinders by welding or brazing is authorized.

Q3. How would one apply for a special permit to manufacture modified 4B steel cylinders that are not in compliance with § 178.50?

A3. Instructions for applying for a special permit are located in 49 CFR, Part 107, Subpart B, Special Permits, § 107.105. For further questions about special permitting, contact the Pipeline and Hazardous Materials Safety Administration, Office of Hazardous Materials Safety, Approvals and Permits Divisions at 202-366-4535.

I hope this answers your inquiry. If you need additional assistance, please contact this office at (202) 366-8553.


Robert Benedict
Chief, Standards Development Branch
Standards and Rulemaking Division

173.181(c), § 173.181(c)(1), 173.181 (c)(1) through (3), 178.50, 107.105

Regulation Sections

Section Subject
107.105 Application for special permit
173.181 Pyrophoric materials (liquids)
178.50 Specification 4B welded or brazed steel cylinders