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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

1

Introduction

In the United States, large-diameter transmission pipelines transport gas and liquid commodities in large volumes over long distances. The country’s network of transmission pipelines consists of about 300,000 miles of gas pipeline and 230,000 miles of hazardous liquid pipeline. Gas transmission pipelines primarily transport natural gas but also carry other flammable, toxic, and corrosive gases; hazardous liquid pipelines transport a variety of liquid products, including crude oil, liquid carbon dioxide, refined petroleum products, and highly volatile liquids that include anhydrous ammonia and the hydrocarbons propane, butane, and natural gas liquids.

Transmission pipelines are one of the safest and most efficient modes of bulk freight transportation. However, when their integrity is compromised, the consequences can be catastrophic because of the hazardous nature and high volumes of the commodities being transported under pressure and the frequency with which pipelines traverse populated and environmentally sensitive areas. When a pipeline rupture occurs, it can lead to an explosion, fire, asphyxiation hazard, or discharge of toxic material into the environment. The National Transportation Safety Board (NTSB) has been investigating major pipeline ruptures and their causes for more than 50 years, including factors contributing to the severity of outcomes.

Following some its earliest investigations, NTSB concluded that faster actions to isolate the ruptured pipeline segment would have reduced the consequences by limiting the release of hazardous material. These findings led NTSB in 1971 to recommend that the U.S. Department of Transportation (U.S. DOT) conduct studies for the purpose of developing standards

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

for the timely isolation and shutdown of ruptured gas and hazardous liquid pipelines.1

In the years prior to NTSB’s recommendation, U.S. DOT had issued regulations establishing location requirements for shutoff valves on new hazardous liquid and gas transmission pipelines. In the case of gas transmission pipelines, the regulations stipulated that the valves be spaced at intervals depending on the density of the population where the pipeline was located.2 The regulations designated “class” locations from 1 to 4, with 1 representing rural locations and 4 representing densely populated areas and based on the number of buildings and dwellings in the area.3 The maximum valve spacing was set at 10 miles, 7.5 miles, 4 miles, and 2.5 miles, respectively, for Classes 1, 2, 3, and 4. In the case of hazardous liquid pipelines, the regulations were less prescriptive with regard to valve locations, requiring their installation on each side of water crossings but giving the operator discretion to install them in other locations that would minimize damage from releases. For both types of pipelines, the regulations did not define the specific type of shutoff valve that must be installed or its method of activation during an abnormal or emergency event, whether by manual, automatic, or remote operation.

During the 1980s and 1990s, NTSB continued to make recommendations for U.S. DOT to establish standards for the timely shutdown of pipeline segments in emergencies, including recommendations for the installation of automatic and remote-control shutoff valves to supplement or replace manually operated valves. Whereas manual valves must be closed by a person at the site of the valve by turning a wheel, toggling a switch, or pushing a lever, valves operated remotely can be closed by personnel from a control center following notification of a rupture or indications of a release from sensors monitoring pressure levels and flow rates. Automatic shutoff valves deploy on their own when designated pressure or flow-rate thresholds are sensed.4

Following its investigation of a ruptured pipeline that released gasoline in Mounds View, Minnesota, in July 1986, NTSB called on U.S. DOT to require the installation of remote-control valves on hazardous liquid

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1 NTSB. 1971. Special Study of the Effects of Delay in Shutting Down Failed Pipeline Systems and Methods for Providing Rapid Shutdown. Report NTSB-PSS-71-1. Washington, DC.

2 In August 1970, U.S. DOT issued standards for gas transmission pipelines that established new definitions for class locations (35 Fed. Reg., 13248–13276, August 19, 1970).

3 These designations were previously included in the American Society of Mechanical Engineers International standard “Gas Transmission and Distribution Piping Systems” (ASME B31.8).

4 Another type of valve that activates automatically is a check valve, which will block the reverse flow of product when forward flow rates or pressures are reduced below thresholds (e.g., in the event of a rupture).

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

pipelines.5 In this incident, which led to two fatalities after the gasoline ignited in a residential area, the control room personnel who identified the rupture had to dispatch technicians to close the valve manually, a process that took 1 hour and 40 minutes.

NTSB maintained that if the control room personnel had been able to close the valve remotely, the amount of product released into the residential area would have been substantially reduced. Less than a decade later, in March 1994, NTSB investigated a gas transmission pipeline explosion in Edison, New Jersey.6 In this case, the operator took 2.5 hours to close a manual valve while eight apartment buildings burned and 1,500 people were evacuated. In its report, NTSB again called on U.S. DOT to establish requirements for automatic or remote-control shutoff valves in populated and environmentally sensitive areas.

In early 2000, U.S. DOT issued a rulemaking notice proposing a new set of regulations for hazardous liquid pipelines intended to address a number of safety and environmental concerns, including those raised by NTSB pertaining to the timely isolation of ruptures and the use of automatic and remote-control shutoff valves.7 The notice proposed the establishment of regulations obligating operators to assess, repair, and validate through comprehensive analyses the integrity of pipelines that could affect populated locations, areas unusually sensitive to environmental damage, and commercially navigable waterways, which were defined to be high consequence areas (HCAs). Finalized in December 2000,8 the integrity management (IM) rule required hazardous liquid pipeline operators to identify all pipeline segments located in or that could affect an HCA, evaluate the entire range of threats to their integrity, assess the associated risks, and implement other preventive and mitigative measures as appropriate based on the analyses and in addition to measures already required by regulation.

The hazardous liquid pipeline IM rule contains examples of preventive and mitigative measures that should be candidates for consideration by operators, including automatic and remote-control shutoff valves, which are referred to as emergency flow restricting devices (EFRDs). The rule lists factors that an operator should consider when making such decisions, including the swiftness of leak detection and pipeline shutdown capabilities, but it does not stipulate the use of specific and measurable criteria for these evaluations to inform operators’ decisions, such as by specifying a

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5 NTSB. 1986. Pipeline Accident Report: Williams Pipe Line Company Liquid Pipeline Rupture and Fire, Mounds View, Minnesota, July 8, 1986. Report PB87-916502. Washington, DC.

6 NTSB. 1995. Texas Eastern Transmission Corporation Natural Gas Pipeline Explosion and Fire, Edison, New Jersey, March 23, 1994. Pipeline Accident Report PB-95-916501. Washington, DC.

7 65 Fed. Register, 21695–21710. April 24, 2000.

8 65 Fed. Register, 75378–75411, December 1, 2000.

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

maximum shutdown time or expected product release value. The reference to EFRDs as a candidate mitigative measure, rather than a requirement, is consistent with the IM rule’s overall approach that allows operators to make choices about the implementation of risk management measures that exceed regulatory minimums based on their own risk assessment and decision-making processes and pipeline-specific conditions.

In commenting on the IM rule when it was first proposed, NTSB raised concerns about the capability of operators to apply risk management principles to determine the need for additional protective measures and recommended that the rule include more minimum criteria for decision making.9 Other commenters, including the U.S. Environmental Protection Agency, maintained that if the rule requires an operator to conduct a risk assessment to determine whether an EFRD or other protective measure is needed, then it should prescribe a specific risk assessment protocol. In issuing the final rule, U.S. DOT did not establish minimum criteria or assessment protocols for deciding when to install an EFRD but noted that the adequacy of an operator’s analysis and the appropriateness of an operator’s risk reduction decisions would be subject to review during inspections.10

In 2003, U.S. DOT issued a similar IM rule for gas transmission pipelines located in HCAs.11 Since the greatest risks from ruptures by these pipelines are fires and explosions, the HCAs were defined as highly populated areas and sites where people regularly gather or live. In the same manner as the hazardous liquid IM rule, the gas IM rule obligated an operator, informed by threat assessments and risk analyses, to take additional measures beyond those already required in regulation to prevent and mitigate the consequences of a pipeline failure in an HCA. However, unlike the rule for hazardous liquid pipelines, the gas rule required operators to make a specific determination of whether automatic shutoff valves or remote-control valves would be an “efficient means” of adding protection to an HCA. While the rule did not define or provide criteria on how this evaluation of efficiency should be performed or its outcome assessed, it stipulated that the results should be documented for review by inspectors.

When commenting on the proposed gas pipeline IM rule, this time NTSB stated that it generally supported the rule’s key elements, including the obligations for operators to conduct threat and risk assessments to inform risk management strategies. Furthermore, NTSB revisited its recommendation (P-95-1) following the Edison, New Jersey, pipeline rupture that called on U.S. DOT to require operators to install automatic or remote-control shutoff valves on gas main lines in urban and environmentally

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9 65 Fed. Register, 75393, December 1, 2000.

10 Ibid.

11 68 Fed. Register, 69778–69837, December 15, 2003.

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

sensitive areas. In presuming that the gas rule’s requirement for operators to determine whether these safety devices would be an efficient means of adding protection would increase their use, NTSB classified the 1995 Edison recommendation as being “Closed—Acceptable Action.”

NTSB revisited this conclusion a few years later when on September 9, 2010, a 30-inch-diameter segment of a gas transmission pipeline ruptured in a residential area in San Bruno, California. The escaping natural gas ignited, resulting in a fire that destroyed 38 homes and damaged 70 others. Eight people were killed, many others were injured, and residents were evacuated from the area. In investigating the incident, NTSB determined that it took the operator 95 minutes to stop the flow of gas and isolate the pipe segment, as dispatchers and qualified technicians were delayed in locating the rupture site and accessing and closing the manual valves.12 Investigators concluded that the delay in isolating the rupture and stopping the flow of gas had contributed to the extent and severity of property damage and increased risks to residents and emergency responders. As a result, NTSB recommended that U.S. DOT’s Pipeline and Hazardous Materials Safety Administration (PHMSA) (which assumed responsibility for the federal pipeline safety program in 2004) amend its IM regulations to require the use of automatic or remote-control shutoff valves on gas transmission pipelines in HCAs and in Class 3 and 4 locations.13 In doing so, NTSB tempered its earlier confidence in the IM rule, expressing concern about a lack of regulatory criteria and guidance on how operators should determine the need for the valves when considering the evaluation factors cited in the rule, including criteria for assessing the swiftness of pipeline shutdown capabilities.

In passing the Pipeline Safety, Regulatory Certainty, and Job Creation Act of 2011, a year after the San Bruno pipeline rupture, Congress mandated the use of automatic or remote-control shutoff valves, or equivalent technologies, on newly constructed or entirely replaced segments of hazardous liquid and gas transmission pipeline segments when economically, technically, and operationally feasible.14 In compliance, PHMSA issued a final rule in April 2022 requiring operators of gas transmission and hazardous liquid pipelines to install such valves—collectively defined as rupture mitigation valves (RMVs)—on all newly constructed or entirely replaced segments of pipelines with diameters of 6 inches or more.15 In doing so, the rule established a minimum performance standard for an RMV to enable

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12 NTSB. 2011. Pacific Gas and Electric Company Natural Gas Transmission Pipeline Rupture and Fire, San Bruno, California, September 9, 2010. Report PB2011-916501. Washington, DC.

13 NTSB Recommendation P-11-11.

14 Pipeline Safety, Regulatory Certainty, and Job Creation Act of 2011, section 4, 2012. https://www.gpo.gov/fdsys/pkg/PLAW-112publ90/pdf/PLAW-112publ90.pdf.

15 68 Fed. Register, 620940–620992, April 8, 2022.

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

isolation of a rupture in 30 minutes or less (when measured from an operator’s identification of a rupture after notification of a potential rupture). The rule affords operators the ability to propose the use of manual valves as an alternative equivalent technology but only if it can meet the 30-minute standard and the operator can demonstrate that an RMV is technically, operationally, or economically infeasible. The rationale for the 30-minute standard, which was developed after consultations with pipeline advisory committees, is provided in the final rule along with examples of circumstances that could affect feasibility.

In commenting on the final rule, NTSB maintained that the rule’s scope of coverage does not satisfy the 2011 San Bruno recommendation because it applies only to newly constructed or entirely replaced segments of transmission pipelines and would not apply retroactively to existing pipelines.16 At the same time, NTSB noted that in a January 22, 2020, response to another NTSB safety recommendation,17 PHMSA had maintained that it could only issue advisory bulletins for existing pipeline facilities due to a “nonapplication” clause in Title 49 USC § 60104(b) that states the following: “[A] design, installation, construction, initial inspection, or initial testing standard does not apply to a pipeline facility existing when the standard is adopted.” While stating that it believed PHMSA does have the authority to require the installation of RMVs on existing pipelines, NTSB requested that Congress make this authority explicit by exempting RMV installations from the nonapplication clause.

To be consistent with the terminology of the new rule, “RMV” is used in the remainder of this report when referring collectively to automatic shutoff valves, remote-control shutoff valves, and EFRDs.

Box 1-1 provides a timeline summary of the pipeline incidents and NTSB recommendations cited above. It also contains a selection of relevant studies, U.S. DOT rulemakings, and congressional directives on RMVs since the 1960s. Appendix B provides a more detailed timeline.

STUDY ORIGIN AND CHARGE

In 2020, Congress passed the Protecting Our Infrastructure of Pipelines and Enhancing Safety Act of 2020, also known as the PIPES Act of 2020. Section 119 directs U.S. DOT to commission a study by the National Academies of

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16 NTSB. 2022. Evaluation of the US Department of Transportation 2021 Report to Congress on the Regulatory Status of the Safety Issue Areas on the National Transportation Safety Board’s Most Wanted List. https://www.ntsb.gov/news/Documents/NTSB%20Evaluation%20of%20DOT%202021-22%20MWL%20Final.pdf.

17 Official correspondence from Howard R. Elliott, PHMSA Administrator, to NTSB regarding NTSB Recommendation P-19-014, January 22, 2020.

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

Sciences, Engineering, and Medicine (the National Academies) to examine the regulatory standards that govern decisions about the installation of automatic and remote-control shutoff valves on existing gas transmission and hazardous liquid pipelines located in HCAs.

To conduct the study, which is the subject of this report, the National Academies convened (following procedures explained in the Preface) an independent committee of experts in pipeline design and operations, risk analysis and management, accident investigation, economics, public policy, and regulatory design and enforcement. The study committee’s charge (or Statement of Task) was drawn from a legislative directive and is provided in Box 1-2. It calls for the committee to review existing methodologies, standards, and regulatory criteria for deciding when and where an automatic or remote-control shutoff valve, or equivalent EFRD, should be installed on an existing transmission pipeline in an HCA. In doing so, the committee is asked to consider how such criteria and methodologies treat public safety and environmental risks and the economic, technical, and operational feasibility of an RMV installation. The committee is also asked to consider

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

relevant NTSB recommendations and consider issues and problems that can arise when relying on manual shutoff valves in emergencies, including human factors issues and timely access to the valve for closure.

At the time the study was commissioned, PHMSA was nearing completion of its rulemaking on the installation of RMVs on newly constructed and entirely replaced segments of transmission pipelines. In April 2022, the rule was finalized, allowing the committee to consult PHMSA’s rulemaking notice for insight into the agency’s rationale for establishing the conditions and criteria for RMV installation, albeit restricted to applications for newly constructed and entirely replaced segments of pipelines. Informed by its review of the new rule and the other topics in its charge, the committee is asked to make recommendations, as appropriate, regarding regulatory or statutory changes that might be considered at the federal and state levels concerning RMV requirements on existing hazardous liquid and gas transmission pipelines.

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

STUDY APPROACH

To inform its work, the committee invited briefings from subject matter experts from transportation safety and regulatory agencies (including PHMSA and NTSB), the natural gas and hazardous liquid pipeline industries, valve suppliers, research institutions, consulting organizations, and academia. The briefings yielded information on a range of relevant topics, including federal and state regulatory requirements, pipeline operations and monitoring systems, risk analysis methods, IM planning and implementation, pipeline safety performance, and rupture and dispersion modeling. The committee also visited pipeline facilities and met with their engineers, technicians, analysts, and operations and planning personnel. The many consulted experts and their affiliations are listed in the Acknowledgments.

To obtain additional information, the committee consulted data published by PHMSA that provide annually updated statistics on the country’s existing hazardous liquid and gas transmission pipeline networks, including total pipeline mileage, mileage by decade of installation, mileage in HCAs and Class 3 and 4 locations, and mileage by pipe diameter.

Because the PHMSA pipeline database lacks information on valve installations, including their types, spacing, and placement, the committee sought help in obtaining relevant data from industry trade associations representing the gas and hazardous liquid pipeline industries. The industry associations transmitted to their members a committee-developed survey asking for information about the number and types of valves used and average valve spacing distances for pipelines in HCAs and Class 3 and 4 locations. These data proved helpful for understanding many issues pertinent to the study, including current operator practices for using and placing different types of valves on their systems and some of the challenges associated with adding RMVs and replacing or converting manual valves to RMVs.

The committee analyzed PHMSA’s database of pipeline incident reports and reviewed NTSB pipeline accident investigations, PHMSA rulemaking notices, and studies conducted on issues related to RMVs and IM over the past 50-plus years, as summarized above and in Box 1-1. In deliberating over the information obtained from these data sources and consultations with outside experts, the committee sought to fulfill its charge with a consensus set of findings, conclusions, and recommendations on federal policy regarding the installation of RMVs on existing transmission pipelines. Although successful in reaching a consensus on several key issues, committee members differed in their views about the appropriate treatment of RMVs in PHMSA’s regulatory direction and guidance. Accordingly, some of the report’s recommendations reflect this consensus and others were accepted by a large majority of members but with some material differences. One

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×

member dissented from a majority recommendation and provided the reasoning in an appended statement (see Appendix A).

REPORT ORGANIZATION

The remainder of the report consists of five chapters. Chapter 2 provides background on the country’s transmission pipeline networks, the share of pipeline mileage in HCAs, and the types of shutoff valves that are used on pipelines, including the use of RMVs. Chapter 3 describes the current pipeline safety assurance framework, focusing on IM processes and requirements. The chapter describes how federal and state safety regulators evaluate IM programs to verify regulatory compliance. The chapter also discusses in more detail the requirements in the new federal rule mandating RMVs on newly constructed and entirely replaced segments of pipelines.

Chapter 4 contains a review of pipeline incident data and reports of incident investigations. The recent history of pipeline incidents in HCAs and Class 3 and 4 locations is examined to identify trends and patterns in incidents, including reported consequences. The chapter also provides a short synopsis of NTSB and PHMSA findings from investigations of several major pipeline incidents, noting how and when shutoff valves were activated. In an addendum to the chapter, the results of an analysis of the socio-demographic characteristics of communities proximate to pipeline incidents are provided in anticipation that equity impacts of pipeline safety risks and their abatement will receive increasing public policy attention.

Chapter 5 describes the prevalence of RMVs on existing pipelines in HCAs and presents operator-provided estimates of costs associated with installing RMVs and converting manual valves to RMVs. The discussion then turns to how operators make choices about whether to install RMVs on existing pipelines, first by discussing the programs several operators have instituted to prioritize their deployment and then by reviewing operator requirements to consider RMVs specifically and within the broader context of their IM obligations. The discussion in this chapter surfaces several shortcomings in the direction and guidance provided to operators for conducting and documenting their decision criteria for the installation of RMVs. A report summary and the committee’s conclusions and recommendations are provided in Chapter 6.

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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Suggested Citation:"1 Introduction." National Academies of Sciences, Engineering, and Medicine. 2024. Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves. Washington, DC: The National Academies Press. doi: 10.17226/27521.
×
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Next: 2 Background on Transmission Pipelines and Shutoff Valves »
Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves Get This Book
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Since 2022, automatic or remote-control shutoff valves have been required on new hazardous liquid and gas transmission pipelines located in or near populated and environmentally sensitive areas. They are intended to enable faster shutdowns of ruptured pipe segments. However, the requirement for “rupture mitigation valves” does not apply to pipelines installed prior to 2022. This report examines the regulatory requirements that apply and recommends options for making sounder decisions about when to install these valves.

TRB Special Report 349: Ensuring Timely Pipeline Shutdowns in Emergencies: When to Install Rupture Mitigation Valves from the Transportation Research Board of the National Academy of Sciences, Engineering, and Medicine is the product of an expert committee convened to assess regulatory standards and criteria for deciding when the valves should be installed on pipelines. This review, which was mandated by Congress, issues a series of recommendations designed with pipeline safety in mind.

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