Interpretation Response #15-0062 ([Authorized Testing Inc, IA02] [Mr. David Bacca])
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name: Authorized Testing Inc, IA02
Individual Name: Mr. David Bacca
Location State: CA Country: US
View the Interpretation Document
Response text:
September 21, 2015
David R. Bacca
Program Manager / Executive Technical Assistant
Authorized Testing Inc., IA02
2522 Kansas Ave.
Riverside, CA 92507-2637
Ref. No. 15-0062
Dear Mr. Bacca:
This is a response to your March 25, 2015 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to Specification 4B welded or brazed steel cylinders. In your email, you state that you are an approved independent inspection agency (IA02) for the manufacture of Department of Transportation (DOT) pressure vessels. You note that the current language in § 178.50(a) states:
"Type, size, and service pressure. A DOT 4B is a welded or brazed steel cylinder with longitudinal seams that are forged lap-welded or brazed and with water capacity (nominal) not over 1,000 pounds and a service pressure of at least 150 but not over 500 psig. Cylinders closed in by spinning process not authorized."
You further note that the language in § 178.50-2(a) previously stated:
"Type and size. Must be welded or brazed type; longitudinal seams must be forged lap-welded or brazed; not over 1,000 pounds water capacity (nominal). Cylinders closed in by spinning process not authorized."
In your email, you assert your belief that the current language is incorrect and does not recognize that the previously-worded requirement did not require a longitudinal weld. Rather, it was implied that if one elected to have a longitudinal weld it would be required to meet the referenced weld / brazing criteria. You ask what prompted this HMR language change and when it occurred, and request an interpretation on the manufacture and continued use of DOT Specification 4B welded or brazed steel cylinders manufactured without a longitudinal weld.
Under rulemaking HM-220B [61 FR 25940; May 23, 1996], we restructured the cylinder specification requirements by consolidating repetitive requirements and implementing other formatting changes. However, in doing so, the language for a DOT Specification 4B cylinder was inadvertently changed to the way it reads currently. Prior to HM-220B, a longitudinal seam was an option (i.e. not mandatory). However, after HM-220B, a longitudinal seam appears to be mandatory. That was not our intention as indicated by the requirement in § 178.50(f)(1)(i), and we thank you for bringing this matter to our attention. PHMSA will revise this language in a future rulemaking.
I hope this information is helpful. If you have any more questions, please do not hesitate to contact this office.
Sincerely,
T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division
178.50(a), 178.50-2(a), 178.50(f)(1)(i)
Regulation Sections
| Section | Subject |
|---|---|
| 178.50 | Specification 4B welded or brazed steel cylinders |