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Interpretation Response #10-0019R ([Mr. John Cox])

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

Interpretation Response Details

Response Publish Date:

Company Name:

Individual Name: Mr. John Cox

Location State: GA Country: US

View the Interpretation Document

Response text:

January 7, 2011

 

 

 

Mr. John Cox

Fire Chief

P. O Box 21

Jamaica, Iowa 50128

Ref. No.: 10-0019R

Dear Mr. Cox:

It has been brought to our attention that our response to your January 31 email regarding the condemnation criteria in the Hazardous Materials Regulations (HMR; 49 CFR parts 171-180) applicable to DOT-3AL cylinders manufactured of 6351-T6 aluminum alloy was incomplete. Specifically, you asked about conflicting condemnation criteria in § 180.209(m), Appendix C of Part 180, and CGA Pamphlet 6.1 regarding these cylinders.

In our April 28, 2010 letter, Ref. No.: 10-0019, we said the following:

Section 180.205(f)(4) requires each specification cylinder manufactured of 6351-T6 aluminum alloy used in self-contained underwater breathing apparatus (SCUBA), self-contained breathing apparatus (SCBA), or oxygen service to be inspected for sustained load cracking (SLC) in accordance with Appendix C of Part 180 every five years. The inspection must include both a visual inspection and an eddy current examination. Each cylinder with SLC that has expanded into the neck threads must be condemned in accordance with

§ 180.205(i). That is, the cylinder must be condemned when evidence of cracking exists to the extent that the cylinder is likely to be weakened.

As prescribed in Appendix C of Part 180, visual examination of the neck and shoulder area of the [DOT 3AL] cylinder [described above] must be conducted in accordance with CGA Pamphlet 6.1. Cylinders with cracks must be condemned, and repair of neck cracks is not allowed. If the visual inspection does not identify cracks in the neck and shoulder area that would require condemnation of the cylinder, it must be subjected to an eddy current examination. If the eddy current examination reveals any crack in the neck or shoulder area of two thread lengths or more, the cylinder must be condemned.

In our April 28, 2010 response, we inadvertently provided partial information in the last sentence of the last paragraph. This letter is intended to clarify the requirements regarding condemnation criteria specified in Appendix C of Part 180. The correct response is "[I]f the eddy current examination combined with a visual inspection reveals any crack in the neck or shoulder area of two thread

lengths or more, the cylinder must be condemned". Therefore, the letter designated as Ref. No.:

10-0019 is retracted and replaced by this letter, Ref. No.: 10-0019-R.

We apologize for any misunderstanding, and hope that it has not caused any inconvenience.

Sincerely,

 

Charles E. Betts

Director

Standards and Rulemaking Division

cc: Fred A. Nachman



180.209(m), 180.205

Regulation Sections

Section Subject
180.205 General requirements for requalification of specification cylinders
180.209 Requirements for requalification of specification cylinders