{"operation":"document","citation":"70 FR 11768","title":"Hazardous Materials: Requirements for UN Cylinders","source_type":"rulemaking","agency":"Pipeline and Hazardous Materials Safety Administration","status":"proposed","official":true,"published_on":"2005-03-09","effective_on":null,"summary":"PHMSA proposes to amend the Hazardous Materials Regulations (HMR) to adopt standards for the design, construction, maintenance and use of cylinders and multiple-element gas containers (MEGCs) based on the standards contained in the United Nations (UN) Recommendations on the Transport of Dangerous Goods. Aligning the HMR with the UN Recommendations will promote flexibility, permit the use of technological advances for the manufacture of pressure receptacles, provide for a broader selection of pressure receptacles, reduce the need for exemptions, and facilitate international commerce in the transportation of compressed gases.","machine_formats":{"json":"https://regulus.evalyn.ai/document/federal-register-05-3859.json","markdown":"https://regulus.evalyn.ai/document/federal-register-05-3859.md"},"app_url":"https://regulus.evalyn.ai/document/federal-register-05-3859","source_url":"https://www.federalregister.gov/documents/2005/03/09/05-3859/hazardous-materials-requirements-for-un-cylinders","body":"Federal Register, Volume 70 Issue 45 (Wednesday, March 9, 2005) [Federal Register Volume 70, Number 45 (Wednesday, March 9, 2005)] [Proposed Rules] [Pages 11768-11801] From the Federal Register Online via the Government Publishing Office [ www.gpo.gov ] [FR Doc No: 05-3859] [[Page 11767]] ----------------------------------------------------------------------- Part III Department of Transportation ----------------------------------------------------------------------- Pipeline and Hazardous Materials Safety Administration ----------------------------------------------------------------------- 49 CFR Parts 107, 171, et al. Hazardous Materials: Requirements for UN Cylinders; Proposed Rule Federal Register / Vol. 70, No. 45 / Wednesday, March 9, 2005 / Proposed Rules [[Page 11768]] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration 49 CFR Parts 107, 171, 172, 173, 178, and 180 [Docket No. PHMSA-2005-17463 (HM-220E)] RIN 2137-AD91 Hazardous Materials: Requirements for UN Cylinders AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), DOT. ACTION: Notice of proposed rulemaking. ----------------------------------------------------------------------- SUMMARY: PHMSA proposes to amend the Hazardous Materials Regulations (HMR) to adopt standards for the design, construction, maintenance and use of cylinders and multiple-element gas containers (MEGCs) based on the standards contained in the United Nations (UN) Recommendations on the Transport of Dangerous Goods. Aligning the HMR with the UN Recommendations will promote flexibility, permit the use of technological advances for the manufacture of pressure receptacles, provide for a broader selection of pressure receptacles, reduce the need for exemptions, and facilitate international commerce in the transportation of compressed gases. DATES: Comments must be received by July 7, 2005. ADDRESSES: You may submit comments to Docket No. PHMSA-05-17463 (HM- 220E) by any of the following methods: Federal eRulemaking Portal: Go to http://www.regulations.gov . Follow the online instructions for submitting comments. Web Site: http://dms.dot.gov . Follow the instructions for submitting comments on the DOT electronic docket site. Fax: 202- 493-2251. Mail: Docket Management System; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590-0001. Hand Delivery: Docket Management System; Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal Holidays. Instructions: All submissions must include the agency name and docket number or Regulatory Identification Number (RIN) for this rulemaking. Comments should identify the docket number (PHMSA-05- 17463). If sent by mail, comments are to be submitted in duplicate. Persons wishing to receive confirmation of receipt of their comments should include a self-addressed stamped postcard. Internet users may access all comments received by the Department of Transportation at http://dms.dot.gov . Note that all comments received will be posted without change to http://dms.dot.gov including any personal information provided. Please see the Privacy Act heading under Regulatory Analyses and Notices. Docket: For access to the docket to read background documents or comments received, go to http://dms.dot.gov at any time or to Room PL- 401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. FOR FURTHER INFORMATION CONTACT: Duane Pfund, telephone number (202) 366-0656, Assistant International Standards Coordinator; Mark Toughiry, telephone number (202) 366-4545, Office of Hazardous Materials Technology; or Sandra Webb, telephone number (202) 366-8553, Office of Hazardous Materials Standards, Research and Special Programs Administration, U.S. Department of Transportation, Washington, DC 20590-0001. SUPPLEMENTARY INFORMATION: List of Topics I. Background II. Overview of Proposed Changes in This NPRM III. UN Pressure Receptacles and MEGCs--Design and Construction Requirements A. Refillable Seamless Steel Cylinders B. Refillable Seamless Steel Tubes C. Refillable Seamless Aluminum Alloy Cylinders D. Refillable Seamless Acetylene Cylinders E. Non-Refillable Metallic Cylinders F. Refillable Composite Cylinders G. MEGCs IV. Pressure Receptacles--Initial and Subsequent Design Type Review and Approval Process V. MEGCs--Initial Design Type Review and Approval Process VI. Qualification and Approval Process for Persons Performing Pressure Certifications A. Inspection Bodies 1. Independent Inspection Agencies (IIAs) 2. Approval Agencies B. Manufacturers C. Requalifiers VII. UN Cylinders and Tubes--Requalification Requirements VIII. Pressure Receptacles--Filling Limits IX. Summary of Proposed Regulatory Changes by Part X. Rulemaking Analyses and Notices I. Background On October 30, 1998, the Research and Special Programs Administration (RSPA), the predecessor agency to the Pipeline and Hazardous Materials Safety Administration (PHMSA, we), published a notice of proposed rulemaking (NPRM) under Docket HM-220 (63 FR 58460). In the NPRM, we proposed, among other changes, to amend the Hazardous Materials Regulations (HMR; 49 CFR parts 171-180) to establish four (4) new metric-marked DOT cylinder specifications to replace twelve (12) current cylinder specifications. The proposed specifications were more performance-oriented than the current DOT cylinder specifications, and were based, in part, on draft standards developed by the International Standards Organization (ISO) and the European Committee for Standardization. Most commenters objected to adoption of specifications based on draft ISO standards. These commenters were concerned that the draft ISO standards could be changed and that cylinders manufactured to the draft standards might not be accepted for transportation in the world market. The commenters requested that we delay consideration of the proposed metric-marked cylinder specifications until the ISO completed its work on the international cylinder standards, and the UN Sub-Committee of Experts on the Transport of Dangerous Goods incorporated the ISO standards into the UN Recommendations on the Transport of Dangerous Goods (UN Model Regulations). Based on the merits of those comments, we agreed that the proposed metric-marked cylinder standards and related proposals that were based on draft ISO standards should not be adopted. On February 13, 2002, we published a notice withdrawing the metric- marked cylinder standards and related proposals and transferring the remaining proposals to Docket No. HM-220D (67 FR 6667) that was finalized August 8, 2002 (67 FR 51626). The UN Model Regulations establish international standards for the safe transportation of hazardous materials. The UN Model Regulations are not regulations, but rather recommendations issued by the UN Sub- Committee of Experts on the Transport of Dangerous Goods (UN Sub- Committee of Experts). These recommendations are amended and updated biennially by the UN Sub-Committee of Experts. They serve as the basis for national, regional, and international modal regulations, [[Page 11769]] including the International Maritime Dangerous Goods (IMDG) Code issued by the International Maritime Organization, and the International Civil Aviation Organization Technical Instructions for the Safe Transport of Dangerous Goods by Air (ICAO Technical Instructions) issued by the ICAO Dangerous Goods Panel. The HMR authorize domestic transportation of hazardous materials shipments prepared in accordance with the IMDG Code if all or part of the transportation is by vessel, subject to certain conditions and limitations, and the transportation of hazardous materials shipments prepared in accordance with the ICAO Technical Instructions for transportation by aircraft and by motor vehicle either before or after being transported by aircraft. Since 1999, the UN Sub-Committee of Experts has been working to develop international standards for the design, construction, inspection, and testing of cylinders and other pressure receptacles for inclusion in the UN Model Regulations. The objective was to develop requirements that can be globally accepted for international transportation, storage, and use. Representatives from the European Industrial Gases Association, the Compressed Gas Association, the European Cylinder Makers Association, the International Standards Organization Technical Committee 58 (ISO/TC 58), and many specialist government officials, including cylinder experts from DOT, participated in the UN Sub-Committee of Experts' efforts. The standards developed for cylinders and other gas receptacles address manufacture, approval, filling, and use. The cylinders and other gas receptacles must be in compliance with ISO standards for design, manufacture, and testing; constructed of materials that are compatible with the gas to be contained in the cylinder, as established in ISO standards; and periodically inspected according to ISO standards. The standards were adopted by the UN Sub-Committee of Experts in 2001 and 2004 and are included in the 13th and 14th Edition of the UN Model Regulations. Cylinders manufactured in accordance with these requirements are marked with the internationally recognized UN mark, which ensures that the cylinders are acceptable world-wide. The continually increasing amount of hazardous materials transported in international commerce warrants the harmonization of domestic and international requirements to the greatest extent possible. Harmonization serves to facilitate international transportation and at the same time ensures the safety of people, property and the environment. While the intent of the harmonization rulemakings is to align the HMR with international standards, we review and consider each amendment on its own merit. Each amendment is considered on the basis of the overall impact on transportation safety and the economic implications associated with its adoption into the HMR. Our goal is to harmonize without sacrificing the current HMR level of safety and without imposing undue burdens on the regulated public. To this end, we are proposing to adopt the UN standards for cylinders (pressure receptacles limited to a water capacity of 150 L), tubes (pressure receptacles with a water capacity exceeding 150 L and not more than 3,000 L capacity), cylinder bundles (cylinders held together in a frame and manifolded together with up to a total water capacity of 3,000 L or 1,000 L for toxic gases), and multiple element gas containers (MEGCs) into the HMR. Our proposal does not remove existing requirements for DOT specification cylinders; rather, we propose to incorporate the UN standards so that a shipper may use either a DOT specification cylinder or a UN standard pressure receptacle as appropriate for individual gases and circumstances. The goal of this rulemaking is to promote flexibility and permit the use of advanced technology for the manufacture and use of pressure receptacles, to provide for a broader selection of authorized pressure receptacles, reduce the need for exemptions, and to facilitate international transportation. DOT technical experts participated in evaluating the ISO standards on which the UN Model Regulations applicable to pressure receptacles are based. We believe that the design, manufacturing, and test requirements provide an equivalent level of safety as the DOT cylinder requirements. Copies of the ISO standards are available for review in the public docket for this rulemaking. The public docket may be viewed in Room PL-401 of the Nassif Building, 400 7th Street, SW., Washington, DC 20590. II. Overview of Proposed Changes in This NPRM This NPRM proposes to amend the HMR to incorporate: --Design, construction and testing requirements for refillable seamless aluminum alloy cylinders conforming to ISO 7866; --Design, construction and testing requirements for refillable seamless steel cylinders conforming to ISO 9809-1, ISO 9809-2, and ISO 9809-3; --Design, construction and testing requirements for non-refillable metallic cylinders conforming to ISO 11118; --Design, construction and testing requirements for composite cylinders conforming to ISO 11119-1, 11119-2 and 11119-3, with certain limitations; --Design, construction and testing requirement for refillable seamless steel tubes with a water capacity between 150 L and 3,000 L conforming to ISO 11120; --Design, construction and testing requirements for UN acetylene cylinders conforming to applicable ISO standards, except the cylinders must be refillable, made of stainless steel, filled with a suitable quantity of solvent (solvent-free not authorized) and fitted with suitable fusible plugs; --Design, construction and testing requirements for MEGCs; --Requalification of UN pressure receptacles, including pressure receptacles installed as components of MEGCs; --A quality conformity assessment system for UN pressure receptables consistent with section 6.2.2.5 of the UN Model Regulations; --A 10-year requalification interval for UN pressure receptacles, except for acetylene and composite cylinders and pressure receptacles used for certain specifically named gases; and --Filling densities prescribed in P200 of the UN Model Regulations for UN pressure receptacle or the requirements in proposed Sec. 173.302b or Sec. 173.304b in this NPRM. Consistent with the current HMR, we are proposing to require UN pressure receptacles to meet the pressure relief requirements in Sec. 173.301(f), and aluminum alloy oxygen cylinders to have straight (parallel) threads. In addition, we are proposing to require each new UN pressure receptacle and MEGC design type to be approved by the Associate Administrator and marked with the letters ``USA,'' to identify the United States of America as a country of approval. The USA country of approval marking will be required on all UN pressure receptacles manufactured within or being shipped to, from, or within the United States. III. UN Pressure Receptacles and MEGCs--Design and Construction Requirements The UN Model regulations define four types of gas pressure receptacles--gas cylinder, pressure drum, tube and bundle of cylinders. As defined in the UN Model Regulations, a cylinder is a [[Page 11770]] pressure receptacle with a water capacity not exceeding 150 liters. A pressure drum is a welded pressure receptacle with a water capacity exceeding 150 liters but not more than 1,000 liters. A tube is a seamless pressure receptacle with a water capacity exceeding 150 liters but not more than 3,000 liters. A bundle of cylinders is an assembly of cylinders that is fastened together, interconnected by a manifold and transported as a unit; the total water capacity of the bundle may not exceed 3,000 liters, or 1,000 liters when used for Division 2.3 gases. In this NPRM, we are proposing to adopt the UN Model Regulations requirements for seamless cylinders and tubes, bundles of cylinders, and MEGCs. The ISO has not finalized its design and construction standards for pressure drums or welded cylinders; therefore, we are not proposing to adopt these pressure receptacle requirements in this NPRM. Thus, the term ``pressure receptacle'' as used in this NPRM refers to cylinders and tubes. We are proposing to provide for a wider selection of pressure receptacles by providing for cylinders, tubes, and MEGCs constructed and certified to the referenced ISO standards and Part 178 requirements. Our present DOT certification system for domestically manufactured seamless cylinders, with the exception of the 3B, 3BN and 3E specifications, requires inspections and verifications of newly produced cylinders to be performed by independent inspection agencies (IIAs). With the exception of cylinders manufactured outside the United States and certain exemption cylinders, PHMSA does not conduct an audit of the cylinder manufacturer's operations prior to initial manufacture. In this NPRM, we are proposing to require each facility that manufactures UN pressure receptacles within the United States and foreign manufacturers of UN pressures receptacles used for transporting hazardous materials to, from or within the United States to be approved by the Associate Administrator. Approval of a pressure receptacle manufacturer will be accomplished through approval of: --Each initial pressure receptacle design type. Prior to manufacture, each manufacturer of UN pressure receptacles will be required to have each initial pressure receptacle design type reviewed by an IIA and approved by the Associate Administrator. --The pressure receptacle manufacturer's quality system. Each manufacturer of UN pressure receptacles will be required to have its quality system documented in the form of written policies, procedures, and instructions. A manufacturer's technical knowledge, skill and integrity are some factors that provide assurance to pressure receptacle purchasers and the general public that pressure receptacles comply with the HMR and are safe transport of hazardous materials. The current HMR requirements contain no formalized criteria for the assessment of these factors. Each manufacturer will be required to demonstrate its knowledge and technical expertise by manufacturing a production lot while being audited by PHMSA personnel. --The production IIA. During the production run, this IIA has the responsibility for ensuring that each pressure receptacle produced by the manufacturer conforms to the applicable specification requirements. The current application procedures for IIAs in Subpart I of Part 107 would apply. During PHMSA's audit of the pressure receptacle manufacturer, the production IIA will be required to perform all prescribed inspections and verifications during the production run. --The proposed requirements in Sec. Sec. 178.69 and 178.70 for the design and construction of pressure receptacles are consistent with those in the UN Model Regulations, except as noted in the following discussions. All pressure receptacles and MEGCs designed and constructed in full conformance with the applicable requirements will be marked with the UN designation, the letters ``USA,'' and the manufacturer's approval number. Any UN pressure receptacle or MEGC not marked in this manner and with the letters ``USA'' as a country of approval will not be authorized to be filled, offered or accepted for transportation within the United States. We believe this approach will maintain the high level of safety existing within the United States while facilitating trade worldwide. A. Refillable Seamless Steel Cylinders This NPRM proposes to allow the use of refillable seamless steel cylinders designed, constructed, and tested to the following standards: ISO 9809-1 ``Gas cylinders--Refillable seamless steel gas cylinders--Design, construction and testing--Part 1: Quenched and tempered steel cylinders with tensile strength less than 1100 MPa.'' This standard specifies minimum requirements for the material, design, construction and workmanship, manufacturing processes, and tests at manufacture for refillable quenched and tempered seamless steel gas cylinders with water capacities from 0.5 liter up to and including 150 liters. ISO 9809-1 is applicable to cylinders with a maximum tensile strength of 1,100 MPa for chrome-molybdenum steels or 1,030 MPa for carbon-manganese steels. However, a lower tensile strength applies when there is a risk of hydrogen embrittlement. The materials of construction are similar to those of DOT 3AA specification cylinders made of carbon manganese alloy steel. ISO 9809-2 ``Gas cylinders--Refillable seamless steel gas cylinders--Design, construction and testing--Part 2: Quenched and tempered steel cylinders with tensile strength greater than or equal to 1100 MPa.'' This standard specifies minimum requirements for the material, design, construction and workmanship, manufacturing processes, and tests at manufacture for refillable quenched and tempered seamless steel gas cylinders with water capacities from 0.5 liter up to and including 150 liters. ISO 9809-2 is applicable to cylinders with maximum tensile strength of greater than or equal to 1,100 MPa. ISO 9809-3 ``Gas cylinders--Refillable seamless steel gas cylinders--Design, construction and testing--Part 3: Normalized steel cylinders.'' This standard specifies minimum requirements for the material, design, construction and workmanship, manufacturing processes, and tests at manufacture for refillable normalized or normalized and tempered seamless steel gas cylinders with water capacities from 0.5 liter up to and including 150 liters. Materials for the manufacture of normalized or normalized and tempered gas cylinders are generally classified as carbon-steels, carbon-manganese or manganese-molybdenum steels. The maximum tensile strength for cylinders made from these steels may not exceed 800 MPa. The materials of construction are similar to those of DOT 3A specification cylinders made of carbon or carbon manganese steel. ISO-9809-3 provides that other steels permitted in ISO 9809-1 or ISO 9809-2 for quenched and tempered cylinders may be used and subjected to normalizing and tempering, provided they additionally pass the impact test requirements specified in ISO 9809-1, and the tensile strength does not exceed 950 MPa. Cylinders with water capacities less than 0.5 liter may also be manufactured and certified to ISO 9809-1, 9809-2 and 9809-3. Cylinders conforming to these standards are authorized for compressed, liquefied, and dissolved gases. These ISO 9809 standards require [[Page 11771]] that, following final heat treatment at manufacture, all cylinders except those selected for batch testing must be subjected to a hydraulic proof pressure test or a hydraulic volumetric expansion test. The standards permit the purchaser and the manufacturer to decide whether to perform the proof pressure test or volumetric expansion test. We consider the proof pressure test to be essentially a leak test. We are proposing to require this test to be a volumetric expansion test. The volumetric expansion test measures the cylinder's elastic expansion and ensures the adequacy of the physical properties of each cylinder. Further, this initial elastic expansion measurement offers a reference point, or benchmark, for use by requalifiers in evaluating whether the cylinder's wall elastic expansion remains within the prescribed parameters and the cylinder is safe for continued use. B. Refillable Seamless Steel Tubes This NPRM proposes to allow use of refillable seamless steel tubes designed, constructed, and tested to the following standard: ISO 11120 ``Gas cylinders--Refillable seamless steel tubes of water capacity between 150 L and 3,000 L--Design, construction and testing.'' This standard specifies minimum requirements for the material, design, construction and workmanship, manufacturing processes, and tests at the time of manufacture for refillable quenched and tempered seamless steel tubes with water capacities from 150 liters up to and including 3,000 liters for compressed and liquefied gases. ISO 11120 is applicable to tubes with a maximum tensile strength of less than 1,100 MPa, except tubes intended for hydrogen bearing gases are limited to a maximum tensile strength of 950 MPa. C. Refillable Seamless Aluminum Alloy Cylinders This NPRM proposes to allow use of refillable seamless aluminum alloy cylinders designed, constructed, and tested to the following standard: ISO 7866 ``Gas cylinders--Refillable seamless aluminum alloy gas cylinders--Design, construction and testing.'' This standard specifies minimum requirements for the material, design, construction and workmanship, manufacturing processes, and tests at manufacture for refillable seamless aluminum alloy gas cylinders with water capacities from 0.5 liter up to and including 150 liters. The cylinders are for compressed, liquefied, and dissolved gases, other than acetylene. The UN Model Regulations permit the use of either tapered or straight (parallel) threads in aluminum alloy oxygen cylinders through the incorporation by reference of other ISO standards. However, we are not proposing to allow the use of tapered threads in aluminum alloy cylinders used in oxygen service and transported in the United States. This is consistent with Sec. 173.302(b) of the HMR, which requires each aluminum oxygen cylinder opening to be configured with straight threads only. Requiring the use of straight threads eliminates the possibility of a tapered threaded valve being inadvertently inserted into a straight threaded cylinder opening. Such a mismatch or cross connect could lead to a violent expulsion of the tapered thread valve or unintended release of oxygen. Within the United States, there are 20 million or more DOT 3AL aluminum alloy cylinders in oxygen service equipped with straight threads. Allowing the use of UN aluminum alloy oxygen cylinders with tapered threads, could increase the potential for inserting improper valves, even though the UN cylinders will be marked with the thread type code, e.g. 18P for straight or 25E for tapered. Persons who are not familiar with the ISO thread type codes may assume that the aluminum alloy oxygen cylinder is equipped with straight threads. The European countries have widely used tapered threads for all gas services; therefore, this mismatching concern may not exist. Although our experience within the United States is with straight thread designs, the use of both thread designs may offer certain advantages. We are asking commenters to address the impact of retaining the prohibition against using tapered threads in aluminum alloy oxygen cylinders. D. Refillable Seamless Acetylene Cylinders This NPRM proposes to allow use of refillable acetylene cylinders complying with ISO 9809-1 or ISO 9809-3 and ISO 3807-2 ``Cylinders for acetylene--Basic requirements--Part 2: Cylinders with fusible plugs.'' ISO 9809-1 and ISO 9809-3 specify the details for design of the cylinder shell. ISO 3807-2 specifies the basic requirements for acetylene cylinders with a maximum nominal water capacity of 150 liters, with shells made from steel and equipped with fusible plugs. It includes procedures for type testing, production batch testing, and the methods for determining the maximum permissible settled pressure in acetylene cylinders and the porosity of the porous mass. The UN Model Regulations also allow acetylene cylinder shells to be made of aluminum alloy conforming to ISO 7866. We are not proposing to allow the use of aluminum shells for acetylene cylinders transported in the United States. At manufacture, the cylinder shells are filled with a porous mass material and heat cured. The curing temperatures of the porous mass typically range from 260 [deg]C (500 [deg]F) to 371 [deg]C (700 [deg]F) for 24 to 48 hours, depending on the size of the cylinder, until the filler hardens. Exposing an aluminum cylinder to sustained high temperatures over long periods of time may adversely affect the structural integrity of the aluminum, thus making the cylinders unsafe for transportation. Because of this safety concern, we are proposing in this NPRM not to allow the manufacture and use of UN aluminum acetylene cylinders in the United States. In addition, paragraph 6.2.2.1.3 of the UN Model Regulations allows the manufacture and use of non-refillable acetylene cylinders without fusible plugs. The HMR do not authorize the manufacture or use of non- refillable acetylene cylinders with or without fusible plugs. We have no shipping experience or safety data on the transportation of non- refillable acetylene cylinders. Therefore, we are proposing that acetylene cylinders must be constructed of seamless steel, be refillable and equipped with fusible plugs. We are proposing to prohibit acetylene cylinders not meeting the proposed requirements from transportation and use in the United States. E. Non-Refillable Metallic Cylinders This NPRM proposes to allow use of non-refillable metallic cylinders designed, constructed and tested to the following standard: ISO 11118 ``Gas cylinders--Non-refillable metallic gas cylinders-- Specification and test methods.'' This standard specifies minimum requirements for the material, design, construction and workmanship, manufacturing processes, and test at manufacture for non-refillable metallic gas cylinders of welded, brazed or seamless construction for compressed, liquefied and dissolved gases. As stated above in this preamble, we are proposing not to allow the manufacture or use of non- refillable acetylene cylinders. F. Refillable Composite Cylinders This NPRM proposes to allow use of refillable composite cylinders designed, constructed, and tested to the following standards: ISO 11119-1 ``Gas cylinders of composite construction-- Specification and test methods--Part 1: Hoop wrapped composite gas cylinders.'' This [[Page 11772]] standard specifies requirements for composite gas cylinders up to and including 450 liters water capacity, for compressed or liquefied gases with test pressures up to and including 650 bar. The cylinders consist of a seamless metallic liner over-wrapped with carbon fiber, aramid fiber, or glass fiber (or a combination thereof) in a resin matrix, or steel wire, to provide circumferential reinforcement. ISO 11119-2 ``Gas cylinders of composite construction-- Specifications and test methods--Part 2: Fully wrapped fibre reinforced composite gas cylinders with load-sharing metal liners.'' This standard specifies requirements for composite gas cylinders up to and including 450 liters water capacity, for compressed or liquefied gases with test pressures up to and including 650 bar. The standard addresses fully- wrapped composite cylinders with a load-sharing liner consisting of a seamless metallic liner over-wrapped with carbon fiber, aramid fiber, or glass fiber (or a combination thereof) in a resin matrix, to provide circumferential reinforcement. ISO 11119-3 ``Gas cylinders of composite construction-- Specifications and test methods--Part 3: Fully wrapped fibre reinforced composite gas cylinders with non-metallic and non-load-sharing metal liners.'' This standard specifies requirements for composite gas cylinders up to and including 450 liters water capacity, for compressed or liquefied gases with test pressures up to and including 650 bar. The cylinders are fully-wrapped composite cylinders with a non-load-sharing metallic or non-metallic liner. The cylinders consist of a liner over- wrapped with carbon fiber or aramid fiber or glass fiber, or a mixture thereof, in a resin matrix to provide longitudinal and circumferential reinforcement. Depending on their construction, the UN Model Regulations specify design life for composite cylinders certified to ISO 11119-1, 11119-2 and 11119-3 from a minimum design life of 10 years to an unlimited life. We are proposing to require composite cylinders to be designed and constructed to the unlimited life requirements while limiting the service life to not more than 15 years from the date of manufacture. Under the HMR, composite cylinders are currently authorized for construction only under the terms of a DOT exemption. The 15-year service life limitation is consistent with that imposed on composite cylinders authorized under exemptions. The ISO-11119-3 standard was adopted by the UN Sub-Committee of Experts in December 2004 for the manufacture and use of fully-wrapped composite cylinders with non-metallic and non-load-sharing metal liners. This standard also applies to composite cylinders without liners. Our experience within the United States is with fully-wrapped carbon-fiber reinforced (CFFC) and fiber reinforced plastic (FRP) composite aluminum-lined cylinders. We have no safety data on the use of composite cylinders with non-metallic and non-load-sharing metal liners or without liners. In this NPRM, we are proposing to prohibit in the United States the manufacture and use of fully-wrapped composite cylinders without liners. Under this proposal, ISO-11119-3 cylinders must have either a metallic or non-metallic (plastic) liner. Since the stress distribution of both ISO 11119-2 and 3 designs is handled by the composite shell rather than the liner, the major concern for plastic- lined cylinders made in accordance with ISO 11119-3 is the permeation of toxic and flammable gases at high temperature ranges (130-154 [deg]F). Therefore, in this NPRM we are proposing to prohibit the transportation of toxic gases or toxic gas mixtures meeting the criteria for Division 2.3, Hazard Zone A or B, in ISO 11119-3 cylinders. When used for Division 2.1 materials, the cylinder will be required to have a working pressure not to exceed 62 bar. We are also proposing to prohibit the use of ISO 11119-3 cylinders for underwater breathing applications because of the effects of saltwater on some resins. G. MEGCs A MEGC is an assembly of UN cylinders, tubes, or bundles of cylinders interconnected by a manifold and assembled within a framework. The term includes all service equipment and structural equipment necessary for the transport of the gases. We are proposing to prescribe the design type approval procedures and the manufacturing specification requirements for MEGCs in new Sec. Sec. 178.74 and 178.75 respectively. The proposed requirements are based on the provisions in Sec. 178.275 of the HMR and paragraph 6.7.5 of the UN Model Regulations. IV. Pressure Receptacles--Initial and Subsequent Design Type Review and Approval Process We are proposing to implement a conformity assessment system consistent with section 6.2.2.5 in the UN Model Regulations. Under this conformity assessment system, PHMSA, as the United States Competent Authority, will be responsible for implementing a system for providing overall approval of each pressure receptacle design type, the manufacturer's quality system, and inspection bodies. The conformity assessment system requirements in the UN Model Regulations were adopted on the basis of the requirements in ISO Technical Report 14600. The requirements are based on the practices used in Europe, Canada, and the United States for ensuring that cylinder quality is consistent with that prescribed in the ISO design and construction standards. The initial design type approval consists of an approval of the manufacturer's quality system and of the pressure receptacle design to be produced. (The manufacturer's quality system is discussed later in this preamble.) Under the proposed procedures for approval of the pressure receptacle design type, the manufacturer will select an inspection body, which, as proposed in this NPRM, will be an IIA approved by the Associate Administrator in accordance with the current procedures in Subpart I of Part 107. The manufacturer will submit an application for an initial design type approval to the IIA for review. The IIA will examine the manufacturer's application for an initial design type approval for completeness. If the application is incomplete, it will be returned to the manufacturer with an explanation. If the IIA verifies that the design conforms to the applicable standards and the requirements contained in Part 178 of the HMR, the manufacturer will fabricate a prototype lot of pressure receptacles in accordance with the design specification. The IIA will verify that the prototype lot conforms to the applicable requirements by witnessing the testing of selected pressure receptacles. If the prototype tests indicate that the pressure receptacles conform to all applicable requirements, the IIA will prepare a design type approval certificate and return the certificate documentation to the manufacturer. The manufacturer will submit the design application to the Associate Administrator for approval. Each application for an initial design type approval must contain the information specified in proposed Sec. 178.70, which includes: (1) The manufacturer's name and the manufacturing facility's address; (2) the designation of the pressure receptacle and the relevant pressure receptacle standard; (3) details of any similar approval application submitted to and denied by another country's competent authority; (4) technical documentation required for design type approval, such as design standards, manufacturing drawings, and design calculations; (5) test reports of the manufactured [[Page 11773]] prototype lot; and (6) documentation on the manufacturer's quality system. If the application, design drawings, and quality control documents are found satisfactory, PHMSA will schedule an on-site audit to assess the manufacturing and inspection processes, and test procedures. During the audit by PHMSA personnel, the manufacturer will be required to produce a group of cylinders to the technical standards for which approval is sought. During the production run, the production IIA will perform the required inspections and tests of newly manufactured cylinders. If the procedures and controls are deemed acceptable, test sample cylinders will be selected at random from the production lot and sent to a laboratory designated by PHMSA for verification testing. If the cylinder test samples are found to conform to all the applicable requirements, the Associate Administrator will issue approvals to the manufacturer and the production IIA to authorize the manufacture of the pressure receptacles. The manufacturer will bear the cost of the audit and verification testing. Under the system proposed in this NPRM, a manufacturer will be required to apply for a new design approval from the Associate Administrator for each new pressure receptacle design type or modification to an approved UN design type. A pressure receptacle will be considered to be of a new design, as specified in the referenced ISO design, construction, and testing standards, when: 1. It is manufactured at a different facility; 2. It is manufactured by a different process; 3. It is manufactured from a material with chemical and mechanical properties different from those specified in the standard; 4. Heat treatment differs from that specified in the standard; 5. The base profile has changed (e.g., concave, convex, hemispherical) or there is a change in the base thickness/cylinder diameter ratio; 6. The overall length of the cylinder has increased by more than 50%; 7. The nominal outside diameter has changed; 8. The design wall thickness has changed; 9. The hydraulic test pressure has been increased; or 10. The guaranteed minimum yield strength and/or the guaranteed minimum tensile strength has changed. Requests for subsequent UN design type approvals will be reviewed by an IIA for design type approval, and approved by the Associate Administrator. The production IIA and the manufacturer will retain a set of the pressure receptacle design type approval documents for a minimum of 20 years. PHMSA has the authority to modify, suspend or terminate an approval certificate upon evidence that information upon which the approval was based is fraudulent or substantially erroneous, or such action is necessary to adequately protect against risks to life or property. The conditions for suspension or termination of an approval are in proposed Sec. 178.70. V. MEGCs--Initial Design Type Review and Approval Process We are proposing to require MEGCs to be reviewed by an approval agency with authorization under the procedures in subpart E of Part 107. The elements (pressure receptacle) installed in the MEGC will be approved as described in section IV of this preamble. The application procedure will be similar to that currently prescribed for the approval of IM and UN portable tanks in Se","truncated":true,"body_characters":211558}