# Pipeline Safety: Plastic Pipe Rule

- **operation:** document
- **citation:** 83 FR 58694
- **title:** Pipeline Safety: Plastic Pipe Rule
- **source type:** rulemaking
- **agency:** Pipeline and Hazardous Materials Safety Administration
- **status:** historical
- **official:** true
- **published on:** 2018-11-20
- **effective on:** 2019-01-22
- **summary:** PHMSA is amending the Federal Pipeline Safety Regulations that govern the use of plastic piping systems in the transportation of natural and other gas. These amendments are necessary to enhance pipeline safety, adopt innovative technologies and best practices, and respond to petitions from stakeholders. The changes include increasing the design factor of polyethylene pipe; increasing the maximum pressure and diameter for Polyamide-11 pipe and components; allowing the use of Polyamide-12 pipe and components; new standards for risers, more stringent standards for plastic fittings and joints; stronger mechanical fitting requirements; the incorporation by reference of certain new or updated consensus standards for pipe, fittings, and other components; the qualification of procedures and personnel for joining plastic pipe; the installation of plastic pipe; and a number of general provisions.
- **machine formats:** - **json:** https://regulus.evalyn.ai/document/federal-register-2018-24925.json
- **markdown:** https://regulus.evalyn.ai/document/federal-register-2018-24925.md
- **app url:** https://regulus.evalyn.ai/document/federal-register-2018-24925
- **source url:** https://www.federalregister.gov/documents/2018/11/20/2018-24925/pipeline-safety-plastic-pipe-rule
**body:**

Federal Register, Volume 83 Issue 224 (Tuesday, November 20, 2018) [Federal Register Volume 83, Number 224 (Tuesday, November 20, 2018)] [Rules and Regulations] [Pages 58694-58720] From the Federal Register Online via the Government Publishing Office [ www.gpo.gov ] [FR Doc No: 2018-24925] [[Page 58693]] Vol. 83 Tuesday, No. 224 November 20, 2018 Part II Department of Transportation ----------------------------------------------------------------------- Pipeline and Hazardous Materials Safety Administration ----------------------------------------------------------------------- 49 CFR Part 192 Pipeline Safety: Plastic Pipe Rule; Final Rule Federal Register / Vol. 83, No. 224 / Tuesday, November 20, 2018 / Rules and Regulations [[Page 58694]] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration 49 CFR Part 192 [Docket No. PHMSA-2014-0098: Amdt. No. 192-124] RIN 2137-AE93 Pipeline Safety: Plastic Pipe Rule AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), Department of Transportation (DOT). ACTION: Final rule. ----------------------------------------------------------------------- SUMMARY: PHMSA is amending the Federal Pipeline Safety Regulations that govern the use of plastic piping systems in the transportation of natural and other gas. These amendments are necessary to enhance pipeline safety, adopt innovative technologies and best practices, and respond to petitions from stakeholders. The changes include increasing the design factor of polyethylene pipe; increasing the maximum pressure and diameter for Polyamide-11 pipe and components; allowing the use of Polyamide-12 pipe and components; new standards for risers, more stringent standards for plastic fittings and joints; stronger mechanical fitting requirements; the incorporation by reference of certain new or updated consensus standards for pipe, fittings, and other components; the qualification of procedures and personnel for joining plastic pipe; the installation of plastic pipe; and a number of general provisions. DATES: The effective date of these amendments is January 22, 2019. The incorporation by reference of certain publications listed in the rule is approved by the Director of the Federal Register as of January 22, 2019. FOR FURTHER INFORMATION CONTACT: General Information: Sayler Palabrica, Transportation Specialist, by telephone at 202-366-0559 or by email at [email protected] . Technical Questions: Max Kieba, General Engineer, by telephone at 202-493-0595 or by email at [email protected] . SUPPLEMENTARY INFORMATION: I. Executive Summary A. Purpose of Regulatory Action B. Summary of Regulatory Provisions C. Costs and Benefits II. Background A. Notice of Proposed Rulemaking B. Gas Pipeline Advisory Committee III. Analysis of Comments and Proposed PHMSA Response IV. Standards Incorporated by Reference V. Regulatory Analysis and Notices VI. Section-By-Section Analysis List of Subjects and Amendments to Part 192 I. Executive Summary A. Purpose of Regulatory Action PHMSA is amending the Federal Pipeline Safety Regulations that govern the use of plastic piping systems in the transportation of natural and other gas. This final rule is comprised of amendments that will improve safety, allow for expanded use of plastic pipe products, and allow or require the use of certain materials and practices. The use and availability of plastic pipe have changed over the years with technological innovations in the products and best practices used in plastic pipe installations. Progress in the design and manufacture of plastic pipe and components has resulted in materials with higher strength characteristics. Manufacturers are instituting new practices related to traceability, and operators are incorporating these practices. Together, these measures have the potential to improve pipeline safety and integrity. The pipeline safety regulations have not stayed current with some of these developments. Many of PHMSA's stakeholders have petitioned PHMSA to codify measures from the progress the industry has made; these petitions are detailed below. This final rule amends the Federal Pipeline Safety Regulations (PSR) to incorporate these changes to enhance pipeline safety, respond to petitions for rulemaking, and accommodate innovations in plastic pipe materials and designs. PHMSA received several petitions for rulemaking under 49 CFR 190.331 regarding plastic pipe. Copies of these petitions are available in the docket for this rulemaking (PHMSA-2014-0098) in addition to the dockets initially established for the petitions. The amendments in this rulemaking will address the following petitions: American Gas Association (AGA)--(Docket No. PHMSA 2010- 0011)--Petition to increase design factor of PE pipe 0.32 to 0.4 and incorporate updated ASTM International (ASTM) D2513 (standard for polyethylene (PE) pipe and fittings). Evonik Industries (Evonik) and UBE Industries (UBE)-- (Docket No. PHMSA 2010-0009)--Petition to allow use of Polyamide-12 (PA-12) pipe. Arkema--(Docket No. PHMSA 2013-0227)--Petition to allow use of Polyamide-11 (PA-11) pipe at higher pressures. Gas Piping Technology Committee (GPTC)--Petition to allow above-ground, encased plastic pipe for regulator and metering stations. Federal and State inspectors have noticed issues related to plastic pipe installation that should be addressed in the pipeline safety regulations. For example, the National Association of Pipeline Safety Representatives (NAPSR), an association of State pipeline safety regulators, petitioned PHMSA to establish permanency requirements for pipe markings in Resolution SR 2-01. Approved on September 27, 2001, Resolution SR2-01 encouraged PHMSA OPS to amend 49 CFR 192.63 ``to require marking of all pipe, fittings, and components in such a manner that the markings last for a period of 50 years or the life of the pipe, fittings, and components.'' B. Summary of Regulatory Provisions To address these issues and petitions, PHMSA is amending the PSR in 49 CFR part 192 to update the plastic pipe regulations. This rulemaking limits these changes to new, repaired, and replaced pipelines. The changes include increasing the design factor of PE pipe; increasing the maximum pressure and diameter for PA-11 pipe and components; allowing the use of PA-12 pipe and components; new standards for risers; more stringent standards for plastic fittings and joints; stronger mechanical fitting requirements; new and expanded standards for the installation of plastic pipe; the incorporation by reference of certain the qualification of procedures and personnel for joining plastic pipe; the installation of plastic pipe; new or updated consensus standards for pipe, fittings, and other components; the qualification of procedures and personnel for joining plastic pipe; the installation of plastic pipe; and a number of general provisions. These amendments are described in Part III of this document and in further detail in the Notice of Proposed Rulemaking (NPRM) published May 21, 2015. See 80 FR 29263. C. Costs and Benefits In accordance with 49 U.S.C. 60102, Executive Orders 12866 and 13563, and U.S. DOT policy, PHMSA has prepared an assessment of the benefits and costs of the rule as well as reasonable alternatives. PHMSA released the initial Regulatory Impact Analysis (RIA) concurrent with the NPRM for public review and comment. PHMSA developed the final RIA by incorporating further internal review and input from public comments. PHMSA has published the final RIA concurrent with this final rule, and it is [[Page 58695]] available in the docket. PHMSA quantified positive net benefits of $32.7 million, mostly from cost savings due to the change in the PE design factor. Other changes enhance pipeline safety, expand flexibility in pipe material choice, and incorporate more modern technical consensus standards. PHMSA quantified approximately $391,000 in annualized safety benefits from the revisions to plastic pipe installation requirements. This estimate is based on the historical frequency and consequences of incidents on plastic pipe systems that could have been prevented by the changes in the final rule. PHMSA also determined unquantified safety benefits from enhanced standards for fittings and risers, prohibiting the permanent use of temporary leak repair clamps, and other general provisions. PHMSA estimated that the revised design factor for PE, relaxed restrictions on PA-11, incorporation of PA-12, and updated standards for all three materials would have negligible impacts on pipeline safety. Overall, the rule improves the safety of plastic pipe systems. On the cost side, PHMSA quantified $32 million in cost savings for the revision to the design factor of PE pipe from 0.32 to 0.40. The change in design factor leads to pipe material cost savings as it permits pipe to operate at higher pressures for a given pipe size and wall thickness. PHMSA also determined that the provisions for expanded use of PA-11 and incorporation of PA-12 materials would lead to unquantified cost savings to operators from greater flexibility in pipeline material choice. The other provisions have unquantified costs, however PHMSA expects these to be minimal as they generally incorporate existing industry best practices by incorporating by reference technical consensus standards. II. Background A. Notice of Proposed Rulemaking On May 21, 2015, PHMSA published the Plastic Pipe NPRM and requested feedback and public comments on the proposed changes to the natural gas pipeline safety regulations in accordance with the Administrative Procedure Act, 5 U.S.C. 551 et seq. The comment period closed on July 31, 2015. These comments and all other related rulemaking materials are available in the electronic docket via www.regulations.gov under Docket ID PHMSA-2014-0098. In section III of this document, PHMSA has summarized the regulatory changes proposed in the NPRM and the public's comments regarding those changes. PHMSA has included a detailed response to the public's feedback and comments. B. Gas Pipeline Advisory Committee Under 49 U.S.C. 60115, the Gas Pipeline Advisory Committee (GPAC) is a statutorily mandated advisory committee that advises PHMSA on proposed safety standards, risk assessments, and safety policies for natural gas pipelines. The Pipeline Advisory Committees were established under the Federal Advisory Committee Act, Public Law 92- 463, 5 U.S.C. App. 1-16, and the Federal Pipeline Safety Statutes, 49 U.S.C. ch. 601. The GPAC consists of 15 members, with membership equally divided among Federal and State agencies, the regulated industry, and the public. The GPAC advises PHMSA on the technical feasibility, practicability, and cost-effectiveness of each proposed pipeline safety regulation. On June 1-3, 2016, the GPAC met in Arlington County, VA. Seven members of the GPAC were in attendance: One representing government, three representing the public, and five representing industry. One member representing the public, one representing industry, and one representing government were absent; additionally, there were 3 vacancies for government representatives and one vacancy for a public representative. During the meeting, the GPAC considered the regulatory proposals of the NPRM, discussed the comments on the NPRM from the public and the pipeline industry, and recommended changes to the NPRM. The record of this meeting, including full transcripts, is filed under Docket Number PHMSA-2016-0032, available at both regulations.gov and on the PHMSA meeting page at https://primis.phmsa.dot.gov/meetings/MtgHome.mtg?mtg=113 . The GPAC, in a unanimous vote, found the NPRM, as published in the Federal Register, and the Draft Regulatory Evaluation technically feasible, reasonable, cost-effective, and practicable provided PHMSA incorporated recommended amendments agreed upon by the committee. PHMSA staff has reviewed and incorporated the GPAC's recommendations into this final rule to the extent practicable. Part III of this document summarizes these discussions and recommendations in greater detail under the respective individual topics. III. Analysis of Comments and PHMSA Response In the NPRM published on May 21, 2015, PHMSA solicited public comment on whether the potential amendments put forward in the NPRM would enhance the safety of plastic pipe in gas transmission, distribution, and gathering systems, and on the costs and benefits associated with these proposals. PHMSA received comments on the NPRM from 39 entities, including: Fifteen pipeline operators; Eight pipeline or manufacturer trade associations; Six manufacturers; Five private citizens; Three consultants; Two government entities, including an association of State pipeline regulators; One citizen group; and One pipeline services company. The following subsections summarize PHMSA's proposals, each of the relevant issues raised by commenters concerning those proposals, and PHMSA's response to those comments. Comments and corresponding rulemaking materials received may be viewed at www.regulations.gov under docket ID PHMSA-2014-0098. A. Tracking and Traceability (1) PHMSA's Proposal In the NPRM, PHMSA proposed to amend Sec. 192.3 to define ``traceability information'' and ``tracking information'' and to amend Sec. Sec. 192.321 and 192.375 to establish standards requiring operators to properly and consistently track and trace pipe and components within their system. The proposed tracking information included the location of each section of pipe, the individual who joined the pipe, and components within the pipeline. The proposed traceability information included the location of pipe and components; manufacturer; production; lot information; size; material; pressure rating; temperature rating; and as appropriate, other information such as type, grade, and model. PHMSA proposed to amend Sec. 192.63 to require operators to adopt the tracking and traceability requirements in ASTM F2897-11a, ``Standard Specification for Tracking and Traceability Encoding System of Natural Gas Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances),'' issued in November 2011, (ASTM F2897-11a), and proposed that operators must record the tracking and traceability data and retain it for the life of the pipe. (2) Comment Summary PHMSA received comments supporting the proposed revisions from NAPSR and Dr. Gene Palermo of Palermo Plastics Pipe (P3) Consulting [[Page 58696]] (Palermo). Palermo praised the tracking and traceability standards in ASTM F2897-11a and noted that it would bring American operators more in line with International Standards Organization (ISO) tracking and traceability standards. Though the American Public Gas Association (APGA) had specific concerns about technology and costs, it described the collection of tracking and traceability information as ``a laudable goal'' and further noted that ``operators no doubt wish this capability existed when PHMSA issued advisory bulletins about brittle-like cracking problems with Century Pipe, DuPont Adyl A piping manufactured before 1973 and polyethylene gas pipe designated PE 3306.'' AGA, APGA, the Texas Pipeline Association (TPA), the Northeast Gas Association, National Grid, AGL Resources, Atmos Energy Corporation, CPs Energy, Questar Gas Company, National Fuel Gas Distribution Corporation, SoCal Gas and San Diego Gas and Electric (SDG&E), NiSource Incorporated, and Norton McMurray Manufacturing Company (NORMAC) submitted comments suggesting that the plastic pipe tracking and traceability provisions should be dropped entirely from the rulemaking. Many operators echoed AGAs concern that a tracking and traceability program would be economically significant, and that full consideration of the costs, benefits, and alternatives that program would slow the adoption and implementation of other portions of the rule. Additionally, those commenters maintained that tracking and traceability requirements should be considered in a separate rulemaking for all material and system types, rather than piecemeal and only for plastic pipe in this rulemaking. The commenters suggested that consistent regulation of all system types would avoid regulatory uncertainty. AGA, APGA, National Fuel, NiSource, SoCal Gas and SDG&E, and Southwest Gas (SW Gas) all proposed convening a working group to discuss options for moving forward with a separate, comprehensive tracking and traceability rule. National Grid estimated a compliance cost of $8.1 million a year for 14,968 plastic pipe miles, and SW Gas estimated $10 million to $20 million in startup costs and $1 million to $2 million in annual costs. APGA, the Plastics Pipe Institute (PPI), NORMAC, R.W. Lyall and Company (Lyall), Thomas M. Lael, National Fuel Gas, City Utilities, and TPA submitted comments, indicating that markings should only have to be permanent up to the time of installation. Commenters argued that truly ``permanent'' markings are not currently technically feasible, stating that the information is only needed at the time of installation; after the information has been recorded into a recordkeeping system, the physical markings are no longer necessary. PPI notes that with current technology and practice, markings are designed to last only three years in an underground environment APGA commented that the proposal would be significantly burdensome to small public operators and that it would be reasonable to expect markings to remain intact 20 years after the pipe was made. Lyall requested clarification about what was expected by the term ``permanent markings'' and whether an operator's records were sufficient to meet those requirements. APGA suggested that if PHMSA did move forward with a tracking and traceability program, it should only collect the data required by the six fields prescribed under ASTM F2897-11a: Component manufacturer, manufacturer's lot code, production date, material, type and size. Both Lyall and Continental Industries concurred. PPI noted that deviating from ASTM F2897-11a would require manufacturers to revamp their marking systems away from the standard and would potentially require new barcoding systems. SW Gas suggested that a tracking and traceability working group could potentially revise ASTM F2897 to incorporate any additionally-needed data fields in the future. AGA, Northeast Gas Association (NGA), National Fuel Gas Distribution Corporation (NFGDC), PPI, Lyall, and City Utilities recommended that, regardless of the specific tracking and traceability provision in the final rule, PHMSA should use a ``phased-in'' approach for implementation. City Utilities commented that it was not opposed to the recordkeeping of material data but requested an extended timeframe to create an implementation plan that considered budget costs. Commenters suggested three to five-year phase-in periods for tracking and traceability recordkeeping requirements. The GPAC discussed this topic at length and ultimately recommended that PHMSA phase-in the tracking and traceability provisions by establishing a compliance deadline of one year for ASTM F2897-11a- compliant markings and a deadline of five years for recordkeeping requirements. The GPAC further recommended that PHMSA limit the marking and traceability requirements to the categories in ASTM F2897-11a and revise the permanent marking standard to a requirement that markings on plastic pipe and components be legible at the time of installation. (3) PHMSA Response In response to comments on the tracking and traceability recordkeeping requirements proposed for Sec. Sec. 192.63, 192.321(j) and 192.375(c), PHMSA is delaying final action on these proposals until a later date. PHMSA expects to consider all the comments and the recommendations of the GPAC related to tracking and traceability recordkeeping after further evaluation of the costs and benefits of this issue. These issues may be revisited in either a subsequent final action or a new rulemaking project. Plastic pipe must still be marked with the 16-character ASTM F2897- 11a markings, which are included in the 2012 editions of the material standards for PE and PA-12 pipe. Incorporating the 2012 editions of the material standards help narrow the gap between the regulations and the latest consensus standards, and adopting the 16-character ASTM F2897- 11a markings within those materials standards will help to phase in standardization to how component attributes are marked and eventually captured in asset management systems. The final rule does not include most of the additional marking performance regulations previously proposed in Sec. 192.63(e), such as permanence requirements and instead defers to the language in the material standards. PHMSA notes that some of the standards incorporated by reference in this final rule contain their own durability requirements which also vary on whether the marking is on pipe, fitting or another component. For example, section 7 for respective material specific standards (i.e. ASTM D2513- 12ae1 for PE, ASTM F2785-12 for PA-12 and ASTM F2945-12a for PA-11) states that for pipe all required markings shall be legible, visible, and permanent. The standards go on to say to ensure permanence, markings shall be applied so it can only be removed by physically removing part of the pipe wall, shall not reduce the wall thickness to less than the minimum value of the pipe, not have any effect on the long-term strength of the pipe, and not provide leakage channels when elastomeric gasket compression fittings are used to make joints. The marking section for fittings on the other hand does not have such explicit requirements on durability or mention permanence. The standard for plastic valves, ASME B16.40-2008, states that only certain markings on valves must be [[Page 58697]] permanently affixed, while others can be made by any means. PHMSA is including language in Sec. 192.63(e) that markings must be legible until time of installation based on public comments and GPAC recommendations. The language is intended to provide clarity given the confusion with how the marking portions of the material specific standards (such as ASTM D2513-12ae1 for PE, ASTM F2785-12 for PA-12 and ASTM F2945-12a for PA-11) are written and what the ultimate requirements are. For example, it is not entirely clear in section 7.1 of ASTM D2513-12ae1, ``Standard Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing, and Fittings,'' issued on April 1, 2012, (ASTM D2513-12ae1), whether all required markings (including the 16-character ASTM F2897-11a markings in section 7.6) be ``legible, visible, and permanent'' per the standards or if the permanence requirements only apply to the more conventional print line information in place prior to the 2012 version and the 16-character marking is an additional requirement with different durability requirements. While manufacturers also commented that it was not feasible to make ASTM D2897 markings permanent and readable for several years after installation without additional costs, it is certainly feasible to print markings legible until the time of installation. This new regulatory language addresses issues raised in public comments and by the GPAC concerning confirming the durability of markings, and help ease any potential regulatory burdens as a result of confusion with permanency and durability requirements. Furthermore, PHMSA is still including a one-year implementation period based on public comments and GPAC recommendations to allow manufacturers additional time to incorporate the new requirements, particularly for the 16-character marking. PHMSA understands many manufacturers are already implementing the 16- character marking but some have not yet, with many manufacturers on both sides waiting to get clarity of expectations on durability. In the interim, PHMSA expects all distribution operators to already be collecting some form of tracking and traceability information, since the Distribution Integrity Management Program (DIMP) regulations in Sec. 192.1007(a)(5) require that operators capture and retain data on the location where new pipeline is installed and the material of which it is constructed. B. Design Factor for PE (1) PHMSA's Proposal PHMSA proposed to amend the design pressure equation in Sec. 192.121 to increase the design factor (DF) for PE pipe from 0.32 to 0.40. The design pressure for PE pipe and other thermoplastics are based first on a Hydrostatic Design Basis (HDB) rating, which refers to the categorized long term hydrostatic strength for a given material. The HDB value is sometimes also considered a measure of the ultimate long term strength of the material. Industries then apply an additional design factor multiplier to the HDB rating to account for potential long term effects based on engineering considerations of how the HDB of the material was derived in conjunction with the behavioral properties of the material, and the specific product they are transporting. The allowable design pressure for plastic in Sec. 192.121 is based on a number of factors, including the HDB rating, wall thickness and diameter or standard dimension ratio (SDR), and design factor. An increase in design factor allows for the use of slightly thinner wall to achieve the same design pressure. To illustrate how the design factor affects the design of plastic pipe, examples using the design pressure calculation are shown below. The design pressure formula in Sec. 192.121 is expressed in one of two ways: P = 2 x S x (t/(D-t)) x DF or P = 2 x (S/(SDR-1)) x DF Where S = the HDB rating; t = specified minimum wall thickness; D = specified outside diameter; DF is the design factor; and SDR the standard dimension ratio (ratio of average specified outside diameter to minimum specified wall thickness.) A common pipe material is PE4710 which has an HDB rating of 1600 at 73 [deg]F. A common pipe size is 4-inch PE SDR 11 which has an average specified outside diameter of 4.5 inches and specified minimum wall thickness of 0.409 inches. If these values are applied to the first equation above, the design pressure would be: P = 2 x 1600 x (0.409/(4.5-0.409)) x 0.32 = 102.4 Applying them to the second equation above, design pressure would be: P = 2 x (1600/(11-1)) x 0.32 = 102.4 psi If the design factor is changed from 0.32 to 0.40, it also changes the result of the calculation in the design pressure formula. If an operator wants to maintain an operating pressure of around 102.4 psi with the new design factor, they could do so using a slightly thinner wall pipe of SDR 13.5, or minimum specific wall of 0.333 inches. The formulas below illustrate how the new design factor allows an operator to use the same design pressure with thinner wall pipe. P = 2 x 1600 x (0.333/(4.5-0.333)) x 0.4 = 102.3 psi or P = 2 x (1600/(13.5-1)) x 0.4 = 102.4psi Alternatively, an increase of design factor with use of slightly thinner wall pipe allows an operator to increase throughput and design pressure if all other variables remain the same, as long as the design pressure doesn't exceed the limitations called out in the regulations (such as 125 psi and minimum wall thickness.) The current design factors for thermoplastic pipe were established decades ago based on general experience with materials at the time and attempts at standardization. As an example, water used a 0.5 design factor for decades. For gas pipe, additional safety factors (sometimes also called strength reduction or derating factors) were applied to the water DF: an additional 0.8 multiplier covers long term effects from constituents in fuel gas, and another 0.8 multiplier compensates for use at increased temperatures above 73 [deg]F. If those two multipliers are applied on top of 0.5 DF for water (or 0.5 x 0.8 x 0.8) the resulting DF is 0.32 for gas. On August 14, 2009, PHMSA received a petition from AGA to allow for a 0.40 design factor for PE pipe based on research and technical justifications performed by the Gas Technology Institute (GTI; July 16, 2007) and to include certain limitations by type of material and wall thickness.\1\ A primary justification for considering raising the design factor is consideration of newer, better performing materials of today and changes in other industries like water, but still applying the same safety factors in place for gas. The water industry has changed their safety factor from 0.5 to 0.63 in standards such as ANSI/ AWWA C901-08, Polyethylene (PE) Pressure Pipe and Tubing, \1/2\ in. (13 mm) through 3 in. (76mm), for Water Service (October 1, 2008.) The 2017 edition of PPI TR-4 allows a design factor of 0.63 for plastic water pipe made of certain PE 4710 materials. Applying the same two derating factor multipliers for gas to the newer DF for water (or 0.63 x 0.8 x 0.8) results in a DF of 0.4 for gas. There are [[Page 58698]] additional safety measures applied if operators want to use the 0.4 DF, including the use of newer materials in place today, the application of a minimum wall thicknesses by pipe size, and a maximum pressure of 125psi. --------------------------------------------------------------------------- \1\ Docket No. PHMSA-2011-0011, August 14, 2009. --------------------------------------------------------------------------- Since design pressure for plastic pipe is based on a number of variables, including design factor and wall thickness, an increase in design factor would allow for the use of PE pipe with thinner pipe walls manufactured in accordance with ASTM D2513-12ae1 as long as it doesn't go below the minimum wall thickness for a specific pipe size. (2) Summary of Comments The majority of commenters, including AGA, APGA, PPI, NGA, NAPSR, NFGDC, TPA, Palermo, and SW Gas, supported this proposal, with several suggesting that a higher design factor would incentivize the use of plastic pipe and provide safety and economic benefits due to its low cost and resistance to traditional corrosion risks. Palermo supported the design factor increase to 0.40 and noted the safe operating history of PE pipe operated to that specification in Canada. Palermo further noted that increasing the design factor would make the material more attractive for operators which it claims would have positive impacts on pipeline safety, stating that going to a 0.4 design factor encourages distribution operators to ``extend the use of plastic pipe systems and displace the lower safety related performance of metal pipe with the higher safety related performance of plastic piping system.'' Palermo noted specifically that plastic pipe systems do not face corrosion risks like metallic pipe systems do. AGA, PPI, NGA, Evonik Industries, and the MidAmerican Energy Company (MidAmerican) supported the proposal in general but were opposed to restricting the diameter of PE pipe beyond the limitations in ASTM D2513-14e1. The commenters suggested permitting pipe up to 24 inches as provided in the standard. Evonik Industries, a plastic pipe manufacturer and one of the original petitioners, also requested that PHMSA expand the PE, PA-11 and PA-12 minimum wall thickness tables in Sec. 192.121 to include pipe sizes less-than-or-equal-to one-inch Iron Pipe Size (IPS).\2\ MidAmerican further requested the inclusion of one- inch Copper Tubing Size (CTS) (another size standard) as a pipe size. --------------------------------------------------------------------------- \2\ Iron pipe size (IPS) is a pipe size standard still used for polymer pipe. --------------------------------------------------------------------------- AGA and TPA requested that the proposal for an increased design factor for PE pipe should be applied retroactively to existing pipe made of PE2708 and PE4710. ASTM introduced those compounds in 2008 in ASTM D2513-08b ``Standard Specification for Thermoplastic Gas Pressure Pipe, Tubing, and Fittings.'' The Iowa Utilities Board (IAUB) stated that the wall-thickness tables in the rule should use Standard Dimension Ratio (SDR) rather than Dimension Ratio (DR) in the column heading to be consistent with the design formula for plastic pipe in Sec. 192.121. Additionally, for ease of use, IAUB recommended including a header on the PE and PA tables in Sec. 192.121 indicating to what materials they apply. DTE Energy (DTE) opposed the proposed 0.090-inch minimum wall thickness for plastic pipe and suggested that PHMSA should retain the current 0.062-inch minimum for PE pipe that they have used in Michigan since 1967. DTE further commented that operators should be allowed to apply the design formula in Sec. 192.121(a), based on the intended use and operating pressure of the pipe, to dictate the minimum required wall thickness. The PVC Pipe Association, a trade group representing PVC pipe manufacturers, submitted comments broadly opposing PHMSA's proposal to modify the allowed design factor of PE Pipe. The Association opposed the less-conservative design factor of 0.40 until operators could gain more field experience with PE pipe operating at the higher factor. In supporting documentation, the PVC Pipe Association hypothesizes that certain high-density polyethylene (HDPE) pipe grade compounds can be susceptible to microscopic crack propagation in high-pressure water service, though it acknowledged that newer compounds may be more crack- resistant. The GPAC recommended minor changes to the minimum wall thickness tables to add additional items, and that PHMSA research the procedural possibility of incorporating the more recent ASTM D2513-14e1, which allows PE pipe with a larger maximum diameter. The Committee further requested that PHMSA research the possibility of applying the new design factor retroactively to existing pipe with the same material characteristics specified in the rule. Members of the Committee and representatives of PPI and AGA commented that, except for the diameters allowed currently, ASTM D2513-12ae1 is not significantly different from either the editions issued before or after it. Therefore, allowing previously installed pipe to operate at the increased design factor or allowing the higher diameters permitted in the 2014 standard should be acceptable. (3) PHMSA Response In consideration of the comments, PHMSA is revising the final rule to include pipe sizes smaller than one-inch IPS and certain one-inch CTS pipe sizes on the tables for each of the materials modified in the final rule. Specifically, in this final rule, PHMSA has revised the proposed PE wall thickness and the SDR table in Sec. 192.121(c)(iv) for clarity and to include \1/2\' and \3/4\' IPS and CTS sizes. The omission of these smaller-diameter specifications was an oversight; PHMSA did not intend to restrict the use of small-diameter plastic pipe. PHMSA will also revise the PE, PA-11, and PA-12 tables per the recommendations of the IUB for consistency and ease of use. In response to comments from DTE, PHMSA notes that the 0.090-inch minimum wall thickness applies to pipes operating at the new 0.40 design factor. At 0.32, operators may still use the design formula in Sec. 192.121 in accordance with the applicable standard. PHMSA is not lowering the minimum wall thickness for 0.40 design factor pipe, as the more conservative wall thickness is necessary to mitigate sidewall fusion and tapping risks, among others, that exist at the higher design factor. PHMSA notes that while AGA and TPA are correct in their assessment that the design requirements for PE2708 and PE4710 pipe under ASTM D2513-08b are the same as the newly incorporated ASTM D2513-12ae1 edition, this subpart is non-retroactive, therefore, the previous maximum design factor would still apply to existing pipelines. PHMSA disagrees with comments from the PVC Pipe Association; the supporting data provided in the AGA petition provides proper safety justification for the revised maximum design factor. As described further in the petition, a battery of tests was performed on pipe to evaluate the combined influence of increased internal pressures and other add-on stresses including effects of squeeze-off, rock impingement, surface scratches, earth loading, and bending stresses on the pipe wall. Various types of joints (butt heat fusion, saddle fusion, electrofusion and mechanical joining) were also subjected to long term sustained pressure testing at elevated temperatures. No failures were observed. Both the petition and the final rule do provide minimum wall thickness requirements for an added safety measure. The Vinyl Institute's comments studying the history of legacy [[Page 58699]] plastic pipe materials in high-pressure water service is not directly applicable to evaluating the operation of modern PE compounds in gas service. PHMSA has considered, as requested by the GPAC, the possibility of incorporating a more recent edition of ASTM D2513 and permitting retroactive applicability of the 0.40 design factor. PHMSA is not in the position to adopt the more recent ASTM D2513-14e1, which includes the increased maximum diameter, since this is beyond the scope of the NPRM and PHMSA has not solicited comment on such a proposal. PHMSA will evaluate the new standard and diameter revision for inclusion in future rulemakings. C. Expanded use of PA-11 Pipe (1) PHMSA's Proposal In the NPRM, PHMSA proposed to amend part 192 to allow pipelines made of certain modern PA-11 compounds to operate at pressures up to 250 pounds per square inch gauge (psig) and permit installation of PA- 11 pipe with a diameter up to six inches. This would expand the allowable uses of PA-11 from the current regulations which restrict the use of PA-11 pipe to pressures up to 200 psig and nominal pipe sizes of 4 inches or less. Arkema, the plastics manufacturer that petitioned for this change, cited the growing history of safe operation of PA-11 pipe since 1999 either under special permit or the current restrictions. PHMSA is also permitting arithmetic interpolation of the allowable pressure equation for PA-11. This would allow consistency with how hydrostatic design basis (HDB) \3\ is already determined for other thermoplastic pipe materials in Sec. 192.121. --------------------------------------------------------------------------- \3\ The HDB is a reflection of a plastic pipe's ability to resist internal pressure over long periods of time. --------------------------------------------------------------------------- Finally, PHMSA proposed incorporating two PA-11 specific standards by reference. Currently, plastic pipe and fittings made of PA-11 must be manufactured in accordance with the much older editions of ASTM D2513 (1987 and 1999) that are referenced for thermoplastic materials other than PE. Adopting ASTM F2945-12a incorporates over a decade of PA-11 material and design advancements. The standard includes requirements for material composition, design, manufacturing tolerances, strength, crack resistance, and quality control for PA-11 pipe and fittings. The final rule also incorporates ASTM F2600-09 as a listed specification for electrofusion fittings on PA-11 pipe. An electrofusion fitting is one with a built-in electric heating element. Passing a current through the fitting bonds the pipe. With new material specific standards being added for PA-11 and other standards being added for components in this rule, there is a need to add F2600-09 for Electrofusion PA-11 fittings, similar to how ASTM F1055 is currently referenced for PE Electrofusion Fittings. Like the PE standard, ASTM F2600-09 sets material and performance requirements for PA-11 electrofusion fittings. In order to meet this standard, a manufacturer must demonstrate test a specimen for minimum hydraulic burst pressure, sustained pressure, tensile strength, impact resistance, and joint integrity. (2) Summary of Comments Nearly all commenters supported this 
- **truncated:** true
- **body characters:** 188176