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Safety Recommendation Details

Safety Recommendation H-09-001
Details
Synopsis: The National Transportation Safety Board investigated three accidents that involved highway vehicles transporting bulk quantities of acetylene gas that occurred between July 25 and October 20, 2007, and reviewed reports of a 2008 overturn accident of another vehicle. The vehicles, called mobile acetylene trailers, carried up to 225 cylinders that were connected by a manifold system1 and filled with acetylene. Two of the accidents occurred as the vehicles overturned on public highways, in East New Orleans, Louisiana, on October 20, 2007, and in Lamar, Colorado, on June 9, 2008. Two of the accidents occurred while the vehicles were being prepared for unloading, in Dallas, Texas, on July 25, 2007, and in The Woodlands, Texas, on August 7, 2007. In the two overturn accidents, cylinders were ejected from the trailers and damaged, releasing acetylene, which ignited. In one unloading accident, the fire on the initial trailer spread to cylinders on an adjacent trailer; in the other, the fire spread to cylinders on adjacent trailers and to nearby buildings and vehicles. The failures of the cylinders on these mobile acetylene trailers and the resultant damage raised concerns about the accident protection provided by these vehicles, the adequacy of the minimum safety standards and procedures applicable to unloading these vehicles, and the adequacy of fire suppression systems at loading and unloading facilities. To address these concerns, the Safety Board conducted a special investigation of mobile acetylene trailers.
Recommendation: TO THE PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION: Modify 49 Code of Federal Regulations 173.301 to clearly require (1) that cylinders be securely mounted on mobile acetylene trailers and other trailers with manifolded cylinders to reduce the likelihood of cylinders being ejected during an accident and (2) that the cylinder valves, piping, and fittings be protected from multidirectional impact forces that are likely to occur during highway accidents, including rollovers.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Alternate Action
Mode: Highway
Location: New Orleans, LA, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA 08 FZ 001
Accident Reports:
Report #: SIR-09-01
Accident Date: 10/20/2007
Issue Date: 3/5/2009
Date Closed: 3/6/2017
Addressee(s) and Addressee Status: PHMSA (Closed - Acceptable Alternate Action)
Keyword(s): Hazmat

Safety Recommendation History
From: NTSB
To: PHMSA
Date: 3/6/2017
Response: With the knowledge gained at the November meeting and after reviewing the CGA’s Pamphlet G-1.6, Standards for Mobile Acetylene Trailer Systems (7th edition, 2011), which the CGA provided to us after the meeting, we believe that you have developed an acceptable alternate method of implementing these recommendations. We had concerns regarding cylinder securement and vehicle accident impact and rollover protection requirements. We now understand that the updated CGA standard requires the cylinders to be secured in a steel framework and fitted with valve protectors to reduce the risk of valve shearing in the event of a vehicle accident impact or rollover. Further, the industry has reduced accident frequency by using electronic logging devices and analyzing driver behavior. We also had concerns regarding the lack of engineering controls to ensure that operators can perform an unloading procedure only correctly and in the proper sequence. We understand that operators are required to undergo extensive training in proper techniques and sequencing, as well as in emergency procedures, and that operations procedures are posted at all facilities. In addition to new construction requirements for fire walls and barriers, all acetylene charging and discharging stations are now required to have an automatic deluge sprinkler system to protect the facility in case of an unintended acetylene release and ignition. We further understand that these new requirements have been in place at all loading and unloading facilities since January 1, 2015. We commend the CGA and the mobile acetylene transport industry for their dedication to safety, as evidenced by the lack of rollover accidents since 2008, and encourage them to continue their efforts to incorporate advanced technologies at their facilities and on their vehicles. These actions constitute an acceptable alternate approach to satisfying Safety Recommendations H-09-1 and -2, which are classified CLOSED--ACCEPTABLE ALTERNATE ACTION.

From: NTSB
To: PHMSA
Date: 10/14/2016
Response: We note that, on June 2, 2016, you published a final rule incorporating, by reference, the Compressed Gas Association’s (CGA’s) Pamphlet G-1.6, Standards for Mobile Acetylene Trailer Systems (7th edition, 2011), to require that mobile acetylene trailers be maintained, operated, and transported in accordance with that document. As you acknowledged, this rule does not address our recommendations regarding cylinder securement or vehicle accident impact and rollover protection requirements. Also, neither the CGA standard nor your rule require engineering controls to ensure that operators can perform an unloading procedure only correctly and in the proper sequence. We appreciate your offer to continue the dialogue on this issue at a meeting where our staffs and CGA representatives can explore a collaborative solution to further improve mobile acetylene trailer safety. Although your final rule did not address our ongoing concerns, your willingness to continue working with us constitutes an acceptable alternate method of implementing these recommendations. Pending completion of these efforts, Safety Recommendations H-09-001 and -002 are classified OPEN—ACCEPTABLE ALTERNATE RESPONSE.

From: PHMSA
To: NTSB
Date: 7/5/2016
Response: -From Marie Therese Dominguez, Administrator: On June 2, 2016, PHMSA published a Final Rule, "Hazardous Materials: Miscellaneous Amendments," in the Federal Register (81 FR 35483) incorporating by reference Compressed Gas Association (CGA) publication G-1.6, Standards for Mobile Acetylene Trailer Systems (ih ed.)(2011 ), and requiring under 49 CFR 173 .301 that mobile acetylene trailers be maintained, operated, and transported in accordance with this industry standard. We believe this action is commensurate with the efforts put forth by PHMSA, the CGA and industry to develop a safety standard for the transport and handling of mobile acetylene cylinders. The requirements adopted under this rulemaking will: ( 1) reduce the likelihood of ejection of cylinders during a highway accident; and (2) protect valves, piping, and fittings from impact forces that may occur during a highway accident. Additionally, CGA G-1.6 addresses assurance that unloading procedures are performed correctly and in sequence by instructing operators to implement standard operating procedures to perform loading or unloading in the specified sequence to minimize the risk of decomposition or flashback. In its comment to the rulemaking, the NTSB states that CGA G-1.6, does not address fully the accident impact protection from multidirectional forces, cylinder securement, or use of equipment to ensure correct sequencing of unloading operations. We acknowledge the NTSB' s concerns, however the recommendations presented in the comment were beyond the scope of the rulemaking. PHMSA, along with CGA representatives, plan to meet with the NTSB to discuss a possible course of action (e.g., modifying further CGA G-1.6) to reconcile the NTSB' s ongoing concerns with PHMSA efforts to address these Safety Recommendations.

From: NTSB
To: PHMSA
Date: 6/12/2015
Response: We are encouraged by your efforts to work with the Compressed Gas Association (CGA) and the International Organization for Standardization to develop the requirements necessary for the design, construction, and operation of mobile acetylene trailer systems. We note that, on January 23, 2015, you published a notice of proposed rulemaking (NPRM) to incorporate by reference the CGA’s Pamphlet G-1.6, Standards for Mobile Acetylene Trailer Systems (7th edition) (2011), and to require that mobile acetylene trailers be maintained, operated, and transported in accordance with that document. We commend your cooperative efforts; however, on March 19, 2015, we submitted comments to the docket expressing our concern that the proposed NPRM changes do not address the cylinder securement, vehicle accident impact, or rollover protection requirements that we recommended. Nor do either the CGA standard or your NPRM require engineering controls to ensure that operators can perform an unloading procedure only correctly and in sequence. We urge you to reconsider your planned regulatory changes to address these shortcomings. Pending publication of a final rule that includes the recommended requirements, Safety Recommendations H-09-1 and -2 are classified OPEN—UNACCEPTABLE RESPONSE.

From: NTSB
To: PHMSA
Date: 3/19/2015
Response: From the NTSB’s comments to Docket No. PHMSA–2013–0225 (HM–218H), Pipeline and Hazardous Materials Safety Administration’s (PHMSA) notice of proposed rulemaking (NPRM), Hazardous Materials: Miscellaneous Amendments, published on January 23, 2015. Standards for Mobile Acetylene Trailers A 2009 NTSB Special Investigation Report discussed four accidents that occurred between July 25, 2007, and June 9, 2008, involving highway vehicles containing bulk quantities of acetylene gas, and reviewed reports of a 2008 accident of another vehicle that overturned. The vehicles, mobile acetylene trailers, carried up to 225 acetylene cylinders that were connected by a manifold system. The vehicles in two of the accidents overturned on public highways: in East New Orleans, Louisiana, on October 20, 2007, and in Lamar, Colorado, on June 9, 2008. Two other accidents occurred while the vehicles were being prepared for unloading: in Dallas, Texas, on July 25, 2007, and in The Woodlands, Texas, on August 7, 2007. In the two overturn accidents, cylinders were ejected from the trailers and damaged, releasing acetylene, which ignited. In one unloading accident, the fire on the initial trailer spread to cylinders on an adjacent trailer. In the other, the fire spread to cylinders on adjacent trailers and to nearby buildings and vehicles. The failures of the cylinders on these trailers and the resultant damage raised concerns about the accident protection provided by these vehicles, the adequacy of the minimum safety standards, and procedures applicable to unloading these vehicles. The NTSB report contained two safety recommendations to PHMSA. (H-09-1 and H-09-2) Cylinder Securement and Impact Protection In the East New Orleans, Louisiana, accident, 32 cylinders were thrown from the vehicle, valves were broken, and the venting acetylene ignited. Postaccident examination of the cylinders also found impact marks that indicated several cylinders struck other cylinders or objects during the vehicle rollover. Given the shock sensitivity of acetylene, impacts sustained during the rollover may have provided sufficient energy to ignite acetylene within intact cylinders. Similarly, in the Lamar, Colorado, accident, about half of the cylinders were thrown from the trailer, with 86 cylinders exhibiting broken valves. The NTSB concluded that the fires in the East New Orleans, Louisiana, and Lamar, Colorado, accidents occurred as a result of the ejection of unsecured cylinders during the rollovers of the mobile acetylene trailers. The resulting damage to many of the cylinders and valves released acetylene, which then ignited. The NTSB further concluded that the HMR covering mobile acetylene trailers did not sufficiently address (1) the protection of the cylinders, valves, and fittings on the trailers from impact forces that occur during an overturn accident and (2) the secure mounting of the cylinders to the vehicles. PHMSA proposes in this NPRM to remedy the lack of cylinder securement and accident impact protection requirements by incorporating by reference the CGA standard G-1.6 (seventh edition [2011]). PHMSA further proposes to revise Title 49 Code of Federal Regulations (CFR) 173.301(g)(1)(iii) to require that mobile acetylene trailers be maintained, operated, and transported in accordance with CGA standard G-1.6. Further, PHMSA seeks comment on the inclusion of CGA Technical Bulletin TB-25, Design Considerations for Tube Trailers to address structural integrity. We note that section 4 of CGA standard G-1.6 discusses mobile acetylene trailer design, and cylinder and piping arrangement. Section 4.1 shows views of typical mobile acetylene trailer system manifold piping. Section 4.2 requires the piping and tubing systems for mobile acetylene trailers to be designed, constructed, inspected, and tested in accordance with applicable requirements of the American Society of Mechanical Engineers Standard B31.3, Process Piping. The CGA standard states that “piping on an acetylene trailer shall be braced and supported to resist strain and vibration normally incident to transportation;” that “tubing and cylinder leads shall be flexible to prevent damage to valves, gauges, and fittings during transit;” and that “cylinder leads connecting cylinders to manifolds shall be designed to resist strain and vibration encountered when the trailer is in transit.” Section 4.3 includes a provision that cylinders shall be transported vertically and secured together as a unit in accordance with the Federal Motor Carrier Safety Regulations at 49 CFR 393.102, which provides performance criteria for cargo securement devices and systems during normal transportation activities. Section 4.3 also specifies “manifolded cylinder valves shall be provided with valve protection meeting the requirements of the HMR (49 CFR Parts 100-185).” However, neither G-1.6 nor the referenced documents address accident impact protection from multidirectional forces that are likely to be encountered during highway accidents, including rollover. Currently, 49 CFR 173.301(i) applies the requirements of CGA TB-25 only to motor vehicle framework for horizontally mounted cylinders longer than 6.5 feet in tube trailers. It does not apply to vertically mounted, manifolded cylinders on mobile acetylene trailers. If the proposed regulation applied accident damage protection provisions of CGA TB-25 to mobile acetylene trailer construction, it would require the valves, pressure relief devices, and other piping components in direct communication with the lading to be installed within the motor vehicle framework; or within a collision-resistant guard, protective device, or housing in compliance with CGA S-1.1, Pressure Relief Device Standards, Part 1, Cylinders for Compressed Gases. If applied to mobile acetylene trailers, the protective device or housing, and the manner of attachment to the vehicle structure would be designed to minimize the loss of product lading when subjected to static loading in all directions, or the overturn of the vehicle, equal to two times the loaded gross weight of the motor vehicle combination. A revision to CGA TB 25 to include vertically mounted, manifolded cylinders would provide a standard for accurate and verifiable performance testing, analytical methods, or a combination thereof, to prove the adequacy of mobile acetylene trailer designs in both normal operation and accident conditions. Contrary to the PHMSA discussion, the proposed changes in the NPRM do not address cylinder securement, vehicle accident impact, or rollover protection as was recommended by the NTSB. Therefore, the NTSB urges PHMSA to reconsider its proposed actions addressing mobile acetylene trailer cylinder securement requirements to fully address these shortcomings in the regulations. Operator Unloading Procedures In the 2009 NTSB Special Investigation Report on Mobile Acetylene Trailer Accidents, the NTSB noted: Federal regulations and CGA guidance concerning mobile acetylene trailers…are silent concerning trailer unloading procedures other than the recommendation that a trained person be in attendance during manual valve operations and when a trailer is being connected or disconnected. [T]he procedures were not sufficient to safeguard against the initiation of a decomposition reaction within the manifold piping and cylinders when simple human errors occurred…The complexity of the unloading procedures and the extreme instability of acetylene together created situations having little or no room for human error…[T]he current acetylene unloading procedures by themselves are not adequate to ensure safety…PHMSA should require fail-safe equipment that ensures that operators of mobile acetylene trailers can perform unloading procedures only correctly and in [the proper] sequence. The NTSB is pleased that CGA standard G-1.6, seventh edition, provides basic minimum requirements for operator training, and the PHMSA proposal to adopt this standard would help to improve the industry practices. However, neither the CGA standard nor the PHMSA-proposed regulatory actions fully address the shortcomings discussed in the NTSB Special Investigation Report. In H-09-02, the NTSB recommended that PHMSA require equipment that ensures that operators perform unloading procedures in the correct sequence. The CGA standard and therefore, the PHMSA-proposed actions only address operating procedure availability to the operator. For installations requiring operation of any equipment by the user, instructions shall be posted and maintained at the discharge location. Where drivers operate valves at discharging stations, the driver shall be in possession of the valve operating instructions. The NTSB notes that each mobile acetylene trailer may have more than 200 acetylene cylinders connected to one or more manifolds for transferring acetylene into or out of the cylinders. Preparing a mobile acetylene trailer for attachment to facility piping and readying it for product transfer must be performed in a precise order to avoid the risk of a catastrophic acetylene decomposition reaction. Each cylinder and manifold has valves that must be shut during transportation and opened in a specific sequence to fill or remove acetylene from the cylinders. Extreme care must be taken to prevent air from entering the manifold, and valves must be slowly opened during acetylene transfer operations. Such a labor-intensive activity is prone to human error, as the NTSB discussed in the Special Investigation Report. Therefore, the NTSB continues to urge PHMSA to revise the regulations to require engineering controls to ensure that operators can only perform an unloading procedure “correctly and in sequence.”

From: PHMSA
To: NTSB
Date: 3/18/2015
Response: -From Timothy P. Butters, Acting Administrator: On January 23, 2015, PHMSA published a notice of proposed rulemaking (NPRM) in the Federal Register (80 FR 3787) proposing to incorporate by reference Compressed Gas Association (CGA) Pamphlet G-1.6, Standards for Mobile Acetylene Trailer Systems (7th ed.) (2011), and proposing to require under 49 CFR 173.301 that mobile acetylene trailers be maintained, operated, and transported in accordance with this document. Additionally, in the notice, PHMSA seeks comment on whether to include CGA Technical Bulletin (TB) TB-25 Design Considerations for Tube Trailers (3rd ed.) to address structural integrity requirements. The comment period for the NPRM closes March 24, 2015. As a result of the highway accidents and the resulting recommendations, the CGA and the International Organization for Standardization (ISO) undertook review of standards applicable to the transportation of bulk quantities of acetylene in cylinders. The CGA convened an ad hoc committee to review and rewrite CGA Pamphlet G-1.6, Standards for Mobile Acetylene Trailer Systems, which contains the minimum requirements necessary for the design, construction, and operation of mobile acetylene trailer systems. The committee included a PHMSA technical representative and industry experts, including representatives from Praxair and Western International Gas & Cylinders, Inc. who operate mobile acetylene trailers. The seventh edition of CGA Pamphlet G-1.6 was completed and published in 2011 and addresses the recommendations and issues identified in the NTSB report. Specifically, CGA Pamphlet G-1.6 addresses: 1) reducing the likelihood of ejection of cylinders during a highway accident by instructing that cylinders must be transported vertically and secured together as a unit in accordance Federal Motor Carrier Safety Regulations (FMCSR; 49 CFR Parts 300-399) for cargo under 49 CFR § 393.102 (i.e., the minimum performance criteria for cargo securement devices and systems, including prevention of vertical movement of loads); and 2) protecting valves, piping, and fittings from impact forces that may occur during a highway accident by instructing that manifolded cylinder valves be provided with valve protection meeting the requirements of the Hazardous Materials Regulations (HMR: 49 CFR Parts 171-180), including retrofit of existing trailers, and if trailer piping and fittings are pressurized to greater than 15 psig (103 kPa) during transportation, instructing that the piping and fittings be protected from multi-directional forces that are likely to occur during highway accidents, including rollovers. Additionally, CGA Pamphlet G-1.6 addresses assurance that unloading procedures are performed correctly and in sequence by instructing operators to implement standard operating procedures to perform loading or unloading in the specified sequence to minimize the risk of decomposition or flashback. This includes guidance on operations associated with the charging (loading), transportation, and discharging (unloading) that should be part of the standard operating procedures, as well as training that employees involved in acetylene operations should receive. Concurrent with the CGA activity, a PHMSA technical representative and CGA members worked with the ISO in developing an ISO standard related to the design, construction, testing, and operation of a cylinder bundle.a ISO 10961 “Gas cylinders--Cylinder bundles--Design, manufacture and testing” includes requirements for the design, construction, and operation of cylinder bundles which are applicable to the transportation of acetylene. CGA Pamphlet G-1.6 is consistent with ISO 10961. The scope of the mobile acetylene trailer industry remains such that there are currently only two companies that we are aware of in acetylene service, as was noted in the NTSB special investigation. Both companies were actively involved in the development of CGA Pamphlet G- 1.6 and are already implementing the standard. We do not anticipate comments opposed to our proposed action and will update the NTSB upon publication of a final rule addressing Safety Recommendations H-09-1 and H-09-2.

From: NTSB
To: PHMSA
Date: 4/29/2010
Response: The NTSB considers the safety advisory (SA) that PHMSA issued on September 6, 2007, a good first step to inform and advise the industry about concerns with the handling of acetylene at cylinder changing plants and for mobile acetylene trailer systems. However, the NTSB points out that an SA, which does not constitute a regulation, cannot alone satisfy Safety Recommendations H-09-1 or -2, which request amendment to regulation 49 CFR 173.301. The NTSB is pleased that PHMSA has been working with the Compressed Gas Association (CGA) and the National Fire Protection Association (NFPA) to address the issue of safe transport and the loading and discharge of acetylene from cylinders. The NTSB is also pleased that PHMSA is working with the CGA to revise CGA Standard G-1.6, Recommended Practices for Mobile Acetylene Trailer Systems, which the CGA has advised will include all NTSB recommendations and issues identified in the SIR and is scheduled for publication in 2010. We also support PHMSA’s work with the International Standard Organization (ISO) in developing two new ISO standards, ISO 10961 and 11372, related to the design, construction, testing, and operation of acetylene cylinder assemblies. The NTSB believes that PHMSA’s continued cooperation with the CGA and ISO to address these issues will be beneficial. Pending the publication of the revised regulation, Safety Recommendations H-09-1 and -2 are classified OPEN -- ACCEPTABLE RESPONSE. The NTSB would appreciate receiving periodic updates on the status of PHMSA’s efforts.

From: NTSB
To: PHMSA
Date: 4/2/2010
Response: The NTSB is currently reviewing the action taken by PHMSA on the above recommendations, identified in your letter, and expects to have a more substantive response back to you shortly. We apologize for the delay in responding regarding some of the recommendations; however, additional documentation was needed for these before their evaluation for closure could be completed. Action on Safety Recommendation R-89-53 (see enclosure) was completed on March 19, 2010.

From: PHMSA
To: NTSB
Date: 3/15/2010
Response: Letter Mail Controlled 3/16/2010 1:16:29 PM MC# 2100096: - From Cynthia L. Quaterman, Administrator: I greatly appreciated meeting with you last month concerning the National Transportation Safety Board's (NTSB) recommendations to the Pipeline and Hazardous Materials Safety Administration (PHMSA). I look forward to meeting with you again, along with staff, on Tuesday, March 16th. Your recommendations, based on lessons learned from accident investigations, provide valuable safety information to our programs. We are committed toconsidering each of the recommendations and implementing those that are positive improvements in safety. I have been meeting with PHMSA's hazmat and pipeline safety programs to assess our actions on the NTSB recommendations. We are addressing these safety issues by taking actions to assure that the "unacceptable actions" are moved into the "open-acceptable" category and to achieve a "closed-acceptable" in a timely manner on as many recommendations as possible. I recognize that a number of "open-acceptable" recommendations are works in progress and maytake a year or more to complete. You indicated your interest in getting these issues resolved as well. As you requested, I asked our pipeline and hazmat staff to compile a copy of outstanding letters to the NTSB that request a change in the classification of a recommendation. I have attached a copy of those letters and am hopeful you and I can successfully resolve a number of these issues. In addition, I have askedour Chief Safety Officer, Cindy Douglass, and our Associate Administrators, Jeff Wiese for Pipeline Safety and Magdy El-Sibaie for Hazardous Materials Safety, to meet with your staff to help us better understand each recommendation and to clarify the actions the NTSB considers necessary for closure. Again, I look forward to meeting with you on these safety concerns and believe that, together, we will make a positive difference in the safe transportation of hazardous materials, including those transported by pipelines.

From: PHMSA
To: NTSB
Date: 5/19/2009
Response: Letter Mail Controlled 5/29/2009 11:25:51 AM MC# 2090336: - From Cynthia Douglass, Acting Deputy Administrator: As a result of these accidents, on September 6, 2007, PHMSA published a safety advisory for persons who use, operate, fabricate, or otherwise handle mobile acetylene trailers (copy enclosed). The notice discussed recent acetylene incidents; requirements in the Hazardous Materials Regulations; national consensus standards issued by the Compressed Gas Association (CGA) and National Fire Protection Association (NFPA); operating procedures, fire mitigation and detection systems; and training of persons who operate, charge, and discharge mobile acetylene trailer systems. We urged companies and workers to review their operating practices to ensure that filling and discharge operations are conducted in the safest possible manner. In addition, we worked with CGA to revise CGA publication G-1.6 entitled “Recommended Practices for Mobile Acetylene Trailer Systems.” On August 29,2008, CGA published the CGA G-1.6, Sixth Edition 2008. Among the major changes included in this edition are provisions to specify that manifolded cylinders must have valve protection that meets the requirements of the Hazardous Materials Regulations and must conform to DOT regulations governing cylinder securement on a trailer; information about installing protective equipment between the acetylene trailer and user’s piping system; a provision that the trailer fill station must conform to NFPA 51A, Standard for Acetylene Cylinder Charging plants; and a provision specifying a minimum burst pressure of 500 psig for the flexible transfer hose used for acetylene withdrawal. We share your concern about the potential safety hazards posed by a fire resulting from the sudden decomposition of acetylene in an accident or during unloading. We met with CGA to discuss NTSB Recommendations H-09-01 and H-09-02. As a result, CGA has undertaken an accelerated revision of CGA publication G-1.6 (Recommended Practices for Mobile Acetylene Trailer Systems) to address the safety issues highlighted in the recommendations. In addition, PHMSA is participating at the International Standard Organization (ISO) in the technical groups responsible for development of new IS0 standards (IS0 10961 and 11372) relating to the design, construction, testing, and operation of acetylene cylinder assemblies. We will continue to work with the CGA and IS0 to explore all possible options for further improvement of current regulations concerning the transportation and safe operation of acetylene cylinders. Based on the actions outlined above, we request that Safety Recommendations H-09-01 and H 09-02 be classified as Open-- Acceptable Action.” We appreciate your consideration of this request. Sincerely, Cynthia Douglass, Acting Deputy Administrator, Enclosure