Thunderbird Cylinder, Inc. — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, D.C. 20590 Mr. Fred A. Nachman Thunderbird Cylinder, Inc. 4209 E. University Drive Phoenix, AZ 85034-73 15 Ref. No.: 06-0276 Dear Mr. Nachman: This is in response to your request for a clarification of the cylinder requalification requirements in the Hazardous Materials Regulations (HMR; 49 CFR Parts 17 1 - 180). Your questions are paraphrased and answered as follows: Q1. Al. 42. A2. 43. A3. 44. Is a leakproofness test required under $ 180.209(g)? If yes, how is the test performed? Yes. Section 180.209(g) specifies that the external visual inspection must be performed on the named cylinders in accordance with either Compressed Gas Association (CGA) C-6 or CGA-6.3, as applicable. CGA C-6 requires the use of soap or other suitable solution to check for leaks. CGA C-6.3 is silent concerning how to detect leaks. Based on the provisions in CGA C-6, a gas sniffer may be used in addition to coating the cylinder with soap or other solution, but not in place of these methods. Under the non-bulk packaging reuse requirements in 5 173.28, paragraph (b)(2)(i) requires packagings subject to the leakproofness test in 8 178.604 to be retested without failure. Does this provision apply to cylinders? No. Section 178.600 specifies that the testing requirements in Part 178, Subpart M ($9 178.600 through 178.609) apply to the performance-oriented packagings identified in Part 178, Subpart L. Cylinder requirements are specified in Part 178, Subpart C and, therefore, are not subject to the leakproofness testing requirements in 5 178.604. Do the HMR require all DOT specification cylinders to be marked with a tare weight? No. Unless otherwise specified in the HMR, DOT specification cylinders are not required to be marked with the tare weight. When should the cylinder requalifer verify the tare weight on a DOT specification cylinder?#

Page 2A4. Currently, the HMR require verification of the tare of DOT 4-series and 8-series cylinders, under certain conditions. See 5 180.209(c) and (i) respectively. I hope this information is helpful. If you have fiuther questions, please do not hesitate to contact this office. Hattie L. Mitchell Chief, Regulatory Review and Reinvention Office of Hazardous Materials, Standards#

Page 35 204 Cy) Drakeford, Carolyn cPHMSA> " A -" .... -- ,-.-.-...-.----- ... -. . -- . . .- , . .. . --Ii!s-t.!.: .!? %. . . - . . From: Mitchell, Hattie <PHMSA> Sent: Friday, December 08,2006 7:43 AM To: fredn Q cyIinder.com Cc: Posten, Ryan <PHMSA>; Hilts, Donald <PHMSA>; Drakeford, Carolyn <PHMSA> Subject: RE: DOT Clarification Tare Wt-Leakproofness 12806.doc Thanks, Fred. We will get a written response to you. Hattie L. Mitchell Chief, Regulatory Review and Reinvention Office of Hazardous Materials Safety Pipeline and Hazardous Materials Safety Administration U.S. Department of Transportation 400 7th Street, S.W. Room 8421 Washington, D.C. 20590-0001 Tel. (202) 366-8553 Fax (202) 366-3012 Website: -gov/ From: Fred A. Nachman [mailto:fredn@cylinder.com] Sent: Thursday, December 07, 2006 11:28 AM To: Mitchell, Hattie <PHMSA>; Hilts, Donald <PHMSA> Cc: Posten, Ryan <PHMSA> Subject: DOT Clarification Tare ~ t - ~ e a k ~ r o o f n e ; ~ 12806.doc Thunderbird Cylinder, Inc. December 8,2006 Mr. Don Hilts Ms. Hattie Mitchell PHMSA, Department of Transportation Room 8100 Div. 41.3 400 7th Street S. W. Washington, D. C. 20509 Dear Don and Hattie, Request for Clarification No. 1- Leah~roofness test: Is a leakproofness test required by 49CFR180.209(g) IYisual inqections of low pressure cylinders who's Records must include. . .conditions checked (e.g., leakage.. .)? , Since it has been verbally interpreted by DOT to be required, how is it to be performed? DOT references. CGA C6-2001 4.2.4 Leaks which states.. .To checkfor leaks the glinder shall be cha~ged and car$ul& examzned.. . Any leakage is cause jor rgection. While it refers to coating with soap or other suitable solutions, is a#

Page 4, - - - ' ---- rage L 01 3 hydrocarbon sniffer acceptable for leakage verification of propane or propylene cylinders if pressurized with their respective gases? If so, is it sufficient to pressurize the cylinder under 49CFR173,28(b)(2)(i) Retested without failure in accordance with 49CF'R 1 78.604 . . . ming. . . at least. . .7.0 psig. . . ? Or, is it necessary to leakproofness check the cylinder at service pressure or proof pressure? Until advised in writing by DOT, Thunderbird shall continue its procedure of utilizing a'hydrocarbon sniffer at 7 psig to verify leakproofness of propane and propylene cylinders being requahfied by Vistlalin@ection. Request for Clarification No. 2- Tare weight verification requirements: In HM-220E, the final rule requires all UN cylinders manufactured after September 11,2006 to have the empg or tare weight in kilograms stamped on the cylinder. Does or should DOT require correct tare weights on (1) all cylinders being manufactured, (2) those cylinders already in service, (3) only those cylinders being filled by weight regardless of their respective levels of corrosion, or (4) none? CGA C6-2001 4.2.1.1 Corrosion limits states (1) When a cylinder exhibits corrosion, the cylinder shall be condemned when the tare weight is less than 90% ofthe original stamped tare we@. A cylinder shall be rejected when the tare weight is less than 95% of the otiginal stamped t a n weight. CGA Technical Bulletin TB-15- 1997 ( R e a f h e d 2004) addresses cylinders that are charged with a liquefied compressed gas by weigh that should be marked with an empg reference weight, i.e., tare weight to include the valve as they are filled by weight. It goes on to direct that each time an operation that my change the tare weight ispefomed on the cylinder such as a valve change, shot blasting, foohing replacement, etc., the tare weight shall be venfed and should be adjusted fthe weight dgersfi-om the marked tare weight more than 1%. The cylinder, then, should be marked with the corrected tare weight prefixed with a “T" and the original tare weight over stamped with "----" s SO as to remain visible. Please note that HM-220E does not reference the "T". Until HM-220E, DOT has never required tare weights on newly manufactured cylinders. It is common to have inaccurate tare weights on cylinders for any of the following reasons: (1) manufacturers stamped entire production lots with the same tare weight without weighing each cyhder, (2) cylinders have had their valves and footrings replaced with those of different weights, (3) cylinders have various amounts of paint or corrosion, (4) cylinders may hold various amounts of liquefied hydrocarbons or water, etc.. Until advised in writing by DOT, Thunderbird will continue its procedure of tare weighting cylinders when requested by its customers. It wdl also continue requiring its customers for whom it is filhng C02 to have tare weights. Thunderbird suggests, moreover, that DOT make a determination and clarify whether or not there is a need for tare weights on all cylinders, since cylinders in one service are frequently converted to C02 or other liquefied services as they age and should have tare weights at the time of requalification and conversion to a liquefied service. Thunderbird Cylinder holds a RIN No. whch authorizes it to requalify cylinders accordng to the CFR's and all referenced materials. It endeavors to train and cerufy its personnel to perform their requalification procedures to be in compliance with those regulatory codes. We have no problem when a client requires us to exceed the regulatory requirements. We do, however, face a dilemma in doing the right thing, specifically, as stated above: (1) how and when do we perform leakproofness tests and (2) when should we verify and retare weight a cylinder? Respectfully,#

Page 5rage 3 or 3 t Fred A. Nachman President (DOT Clalrification Tare W~Leakproofness 12806.doc) 4209 E. University Drive Phoenix, AZ 8 85034-7315 PHONE: 602.437.4600 FAX: 602.437.5052 EMAIL: fredn@cylinder.com#