Rail Transportation of Liquefied Natural Gas: Safety and Regulation

June 12, 2020 – July 28, 2020 R46414

Rail Transportation of Liquefied Natural Gas:
July 28, 2020
Safety and Regulation
Paul W. Parfomak
An emerging alternative to domestic natural gas pipelines is shipping natural gas by rail, creating
Specialist in Energy and
what some refer to as “virtual pipelines.” On April 10, 2019, the Trump Administration issued
Infrastructure Policy
Executive Order 13868, directing the Secretary of Transportation to permit liquefied natural gas

(LNG) shipment in rail tank cars throughout the U.S. rail network. In compliance with the order,
John Frittelli
the Pipeline and Hazardous Materials Safety Administration (PHMSA), in coordination with the
Specialist in
Federal Railroad Administration (FRA), initiated a rulemaking on October 24, 2019. The
Transportation Policy
executive order effectively set a deadline for a final rule of May 10, 2020. PHMSA published the

final rule in the Federal Register on July 24, 2020.

The federal agencies with principal oversight of LNG shipments by rail are PHMSA and FRA,
both within the Department of Transportation. In addition, the National Transportation Safety Board (NTSB) investigates rail
accidents and makes safety recommendations. The Transportation Security Administration (TSA) and PHMSA jointly
oversee freight rail security. The U.S. Coast Guard regulates safety and security of ports, where LNG terminals receiving rail
shipments may be located. Federal safety requirements apply to any train operating in the United States, regardless of origin
or destination. In addition, the rail industry establishes its own consensus safety standards, which often exceed government
requirements.
Vessels have shipped U.S. LNG overseas, and tanker trucks have shipped LNG domestically, for decades. However,
domestic shipment of LNG by rail is new. In 2015, the federal government issued its first ever permit for LNG shipments by
rail in multi-modal tank containers between Anchorage and Fairbanks. A second such approval was issued in 2017 for LNG
shipments in Florida between Jacksonville and Miami. On December 5, 2019, the federal government issued its first special
permit authorizing LNG transport in rail tank cars between Wyalusing, PA, and Gibbstown, NJ. Shipment configurations
could range from a small number of tank cars in trains carrying mixed freight up to dedicated “unit” trains with as many as
100 tank cars of LNG. These approvals and the PHMSA rulemaking have drawn both support and criticism. The freight
railroads and other industry groups support them, citing perceived economic opportunities and their safety record. Some in
Congress also have supported LNG by rail for similar reasons. However, perceived public safety and security risks of LNG
by rail have raised concerns among state officials, the National Transportation Safety Board, and other Members of Congress.
Natural gas is combustible, so an uncontrolled release of LNG poses a hazard of fire or explosion. LNG also poses hazards
because it is so cold. Key safety issues include risk differences between trains carrying only LNG versus trains carrying LNG
and other cargo, derailment risks, tank car crashworthiness, routing near populated areas, and emergency response
capabilities, especially among local first responders. The security implications of LNG shipments by rail are also a
consideration, as LNG shipments and facilities could be targeted by individuals with malicious intent, but also could provide
backup natural gas supplies if pipelines were disrupted.
A 2019 House appropriations bill amendment (H.Amdt. 468 to H.R. 3055) would have prohibited appropriated funds from
being used to carry out the LNG-by-rail provisions of the executive order or to authorize LNG transportation in rail tank cars
by issuance of a special permit or approval; the amendment was not adopted. The House Committee on Appropriations report
(H.Rept. 116-106) accompanying Division H of the Further Consolidated Appropriations Act, 2020 (P.L. 116-94)
recommended FRA funding to research and mitigate risks associated with the rail transportation of LNG, including tank car
research. The Protecting Communities from Liquefied Natural Gas Trains Act (H.R. 4306) would require federal agencies to
conduct further evaluation of the safety, security, and environmental risks of transporting LNG by rail. The Pipeline and
LNG Facility Cybersecurity Preparedness Act (H.R. 370, S. 300) seeks “to ensure the security, resiliency, and survivability”
of LNG facilities and would require DOE to coordinate response and recovery to physical and cyber incidents impacting the
energy sector. The Moving Forward Act (H.R. 2) would require FRA and PHMSA to further evaluate the safety, security,
and environmental risks of transporting LNG by rail, including physical testing and a determination of whether new safety
standards are needed. The bill would authorize between $6 million and $8 million in FRA funding to carry out the evaluation.
It would rescind any special permit or approval for the LNG transportation by rail tank car issued prior to enactment and
would prohibit any regulation, special permit, or approval prior to the conclusion of a specified study period.
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Rail Transportation of Liquefied Natural Gas: Safety and Regulation

Introduction
Domestic transportation of natural gas occurs mainly by pipeline, but some parts of the United
States may have insufficient pipeline capacity to meet expected demand. Although pipeline
developers are expanding the nation’s pipeline network, proposed pipelines in some regions,
notably the Northeast and Mid-Atlantic, have encountered siting challenges. Facing these
challenges, U.S. natural gas producers are pursuing other means to supply markets where pipeline
capacity is constrained. The Trump Administration has been supporting these efforts. As the 2020
Economic Report of the President notes, “pipelines are not the only means of transporting natural
gas domestically.”1
One emerging alternative to transporting natural gas by pipeline is shipment by rail, creating what
some refer to as “virtual pipelines.” In 2015, the federal government issued the first permit
allowing the transportation of liquefied natural gas (LNG) by rail—on one specific route—using
multi-modal tank containers on flatbed railcars. In 2019, the Trump Administration issued
Executive Order 13868, directing the Secretary of Transportation to finalize a rule which would
permit the transportation of LNG in rail tank cars more widely.2 In compliance with this order, the
Pipeline and Hazardous Materials Safety Administration (PHMSA), in coordination with the
Federal Railroad Administration (FRA), initiated a rulemaking on October 24, 2019. The
executive order effectively set a deadline for the final rule of May 10, 2020. PHMSA published
the final rule in the Federal Register on July 24, 2020.3
Large marine vessels have shipped LNG between U.S. and overseas ports for over 60 years and
tanker trucks have transported LNG domestically since the 1970s. Bulk LNG shipments and the
development of related facilities historically have been controversial due to safety and security
concerns.4 However, domestic shipment of LNG by rail is relatively new. The President’s
executive order is intended to provide “greater flexibility in the modes of transportation” of LNG
to serve domestic and export markets. Gas producers and railroads view LNG shipments as “a
growing opportunity” for new revenue and as a way to increase supply reliability.5
This report discusses the physical hazards of LNG as well as safety and security issues associated
with LNG transportation by rail. The report examines relevant federal regulation and summarizes
recent industry initiatives to transport LNG by rail for domestic and export markets. It reviews
Presidential and federal agency efforts to facilitate the movement of LNG by rail and selected
policy issues. The report concludes with a summary of legislative actions in the 116th Congress.
Characteristics of LNG
When natural gas is cooled to temperatures below minus 260° F it condenses into a liquid form,
generally referred to as “liquefied natural gas,” or LNG. As a liquid, natural gas occupies only
1/600th the volume of its gaseous state, so it is stored more efficiently in a limited space and is
more readily transported. At warmer temperatures LNG becomes gaseous again and can be

1 Executive Office of the President, Economic Report of the President, February 2020, p. 169.
2 Executive Order 13868, “Promoting Energy Infrastructure and Economic Growth,” 84 Federal Register 15495, April
14, 2019. The order was issued on April 10, 2019.
3 Pipeline and Hazardous Materials Safety Administration (PHMSA), “Hazardous Materials: Liquefied Natural Gas,”
85 Federal Register 44994-45030, July 24, 2020. (Hereinafter PHMSA Final Rule.)
4 Jamie Smith Hopkins, “Cove Point Project Opponents Raise Safety Concerns,” Baltimore Sun, January 26, 2014.
5 See, for example, Natural Gas Supply Association and the Center for LNG, “NGSA and CLNG Joint Statement on
Executive Order Promoting Energy Infrastructure,” press release, April 10, 2019.
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Rail Transportation of Liquefied Natural Gas: Safety and Regulation

pumped into local natural gas distribution systems, or fed directly into power plants or industrial
facilities.
Safety Hazards of LNG
Natural gas is composed primarily of methane, which is combustible, so an uncontrolled release
of LNG poses a hazard of fire or explosion. LNG also poses hazards because it is so cold. The
possibility of catastrophic releases at LNG production, transfer, and storage facilities, and from
LNG marine tankers, has long been the subject of technical research and congressional interest.6
LNG transportation by rail poses similar hazards, although at smaller scale.
Flammable Vapor Clouds
In the event of an uncontrolled LNG release directly from a tank container or tank car, some of
the LNG will regasify in the warmer, ambient air and form a natural gas vapor cloud. If the
incident causing the release creates a source of ignition (e.g., a spark), the vapor cloud could
begin to burn immediately at the point of release. Burning LNG poses a significant thermal
hazard as it is hotter and burns more rapidly than oil or gasoline fires.7 Its thermal radiation may
injure people and damage property a considerable distance from the fire itself.
Emergency responders are generally unable to extinguish LNG fires, except very small ones. As a
2019 study commissioned by PHMSA reported
LNG releases do not allow first responders to cap off a leak or interact with the container.
LNG releases involving cryogenic gas would result in an immediate evacuation of the area
and securing the adjacent facilities. Given the warming effect of water on cryogenic gases,
putting water on a cryogenic release is not recommended.8
In most cases, therefore, an LNG fire will continue to burn until all the LNG feeding it is
consumed. If the natural gas vapor does not ignite immediately upon release, the vapor cloud may
drift from the site. If the cloud subsequently encounters an ignition source, those portions of the
cloud with a combustible gas-air concentration may burn.9 The nature of such a fire would
depend upon local conditions. Whether an LNG vapor cloud can explode, potentially posing
greater risks to people on the ground, is an open technical question.10
If LNG spills on land without igniting, it will flow away from the source, potentially pooling in
ditches, culverts, sewers, or other lower-lying areas. LNG spilled on water will spread out in a
pool on the surface of the water. The LNG will continue evaporating as it travels, creating a vapor

6 Walter Chukwunonso Ikealumba and Hongwei Wu, “Some Recent Advances in Liquefied Natural Gas (LNG)
Production, Spill, Dispersion, and Safety,” Energy and Fuels, Volume 28 (2014), pp. 3556−3586; Rob M. Pitbaldo and
John L. Woodward, “Highlights of LNG Risk Technology,” Journal of Loss Prevention in the Process Industries, vol.
24 (2011), pp. 827-836.
7 Robert G. Zalosh, Industrial Fire Protection Engineering, John Wiley and Sons, Hoboken, N.J., 2003, Table A.1.
8 Cambridge Systematics, Inc., Risk Assessment of Surface Transport of Liquid Natural Gas, Prepared for the Pipeline
and Hazardous Materials Safety Administration, Office of Hazardous Materials Safety, March 20, 2019, p. 92.
9 Methane, the main component of LNG, burns in gas-to-air ratios between 5% and 15%.
10 PHMSA states that it “is not aware of any reliable reports of explosions of outdoor vapor clouds of natural gas and
does not believe that there is a risk of vapor cloud explosions (VCEs) due to a release of methane in an open area.”
PHMSA, “LNG Safety,” accessed March 18, 2020, at https://www.phmsa.dot.gov/pipeline/liquified-natural-gas/lng-
safety.
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Rail Transportation of Liquefied Natural Gas: Safety and Regulation

cloud over these areas. Any resulting fire could spread farther outward as the LNG flow expands
away from its source and continues evaporating.11
Boiling Liquid Expanding Vapor Explosions
One hazard of particular concern for transportation of combustible fuels in tank containers or rail
tank cars is the possibility of a boiling liquid expanding vapor explosion (BLEVE). As a
Canadian study explained in 2015
This type of accident occurs when a tank car is heated (typically by fire) until rupture, at
which point the vapour suddenly expands and the liquid contents boil rapidly due to the
pressure drop. BLEVEs can result in a blast wave, projection of tank fragments and/or a
fireball.12
Because experience with LNG transport by rail is limited and few experimental studies have
focused specifically on LNG releases from tankers, there are significant uncertainties about the
risk of a BLEVE from an accident involving an LNG tank container or rail car.13 Furthermore, the
assessment of risk must take account of the safety measures (e.g., pressure relief valves)
incorporated into tank and tank car designs, which may vary. Such incidents may not be ruled out
entirely, however, as a BLEVE apparently occurred in Spain in 2002 following a highway crash
involving an LNG tanker truck.14
Other LNG Safety Hazards
LNG vapor clouds are not toxic, but they could cause asphyxiation by displacing breathable air.
Such clouds may begin near the ground (or water surface) at a spill site when they are still very
cold, but rise as they warm because natural gas is lighter than air, diminishing the threat to
people. Extremely cold LNG could injure people or damage equipment (e.g., by brittle fracture)
through direct contact.
Environmental Risks
As noted above, LNG is composed principally of methane. In 2009, the Environmental Protection
Agency (EPA) found that methane endangers public health and welfare within the meaning of the
Clean Air Act because of its effects on climate as a greenhouse gas.15 Operators do not

11 In a 1944 accident with East Ohio Gas involving a release from two very large LNG storage tanks, such LNG flows
were a major contributing factor to the resulting fires: “As the gas vaporized, it flowed through gutters and along curbs
until it reached catch basins and the underground sewage system, causing streets to explode and manhole covers to
blow off. The gas eventually flowed into homes and businesses via the sewage system, causing further explosions,
destruction, and injuries.” See Western Reserve Historical Society, “History of the East Ohio Gas Explosion and Fire,”
at http://catalog.wrhs.org/collections/view?docId=ead/PG575.xml&doc.view=printead;chunk.id=0, accessed May 7,
2020.
12 National Research Council Canada, Rail Tank Cars Exposed to Fire, Report A1-005795-01.1, March 31, 2015, p. 1.
13 Nilambar Bariha, Vimal Chandra Srivastava, and Indra Mani Mishra, “Theoretical and Experimental Studies on
Hazard Analysis of LPG/LNG Release: A Review,” Reviews in Chemical Engineering, vol. 33, no. 4 (2017), pp. 387–
432.
14 Eulalia Planas, Elsa Pastor, Joaquim Casal, and J.M. Bonilla, “Analysis of the Boiling Liquid Expanding Vapor
Explosion (BLEVE) of a Liquefied Natural Gas Road Tanker: The Zarzalico Accident,” Journal of Loss Prevention in
the Process Industries, vol. 34 (2015), pp. 127-138.
15 Environmental Protection Agency, “Endangerment and Cause or Contribute Findings for Greenhouse Gases,” 74
Federal Register 66496-66516, December 15, 2009. For more information, see CRS Report R44615, EPA’s Methane
Regulations: Legal Overview, by Linda Tsang.
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intentionally vent LNG tanks in surface transportation during normal operation. In the event of an
uncontrolled LNG release, methane that is not burned escapes into the atmosphere.16 LNG
dissipates completely and leaves no residue, so other environmental damage at the site of an LNG
release would be confined to fire impacts in the immediate area and freezing impacts on adjacent
facilities or equipment.
Security Risks
After the terror attacks of September 11, 2001, security risks to LNG infrastructure and marine
tankers drew considerable attention.17 Similar concerns may be relevant to movement of LNG by
rail. In particular, some in Congress have expressed concern that individuals with malicious intent
could seek to cause an uncontrolled release of LNG in a populated area to injure people.18 The
potential impact of an attack on a rail shipment of LNG could be considerably greater than that
involving a truck shipment because the volume of LNG involved could be greater. A single LNG
rail tank car can carry over 30,000 gallons of LNG compared to a typical LNG tanker truck which
can carry roughly 13,000 gallons—and rail shipments may consist of multiple connected cars.19
The hazards from an intentional release would be the same as those discussed above; however,
the potential impact might be greater than that of an accident occurring at a random location.
While LNG shipments by rail may increase security risks to local communities and infrastructure,
they may increase the resiliency of the energy sector more broadly. In particular, transporting
LNG by rail may serve as a potential backup for pipeline natural gas supplies. In a December
2018 study, the Government Accountability Office (GAO) stated that since the terrorist attacks of
September 11, 2001, “new threats to the nation’s pipeline systems have evolved to include
sabotage by environmental activists and cyber attack or intrusion by nations.”20 Pipeline
disruptions could interrupt gas supplies to power plants, but LNG transport by rail potentially
could provide emergency fuel supply to critical end users until pipeline supplies could be
restored.21 LNG shipments by rail also could be targeted, but an attack which could shut down a
natural gas pipeline and simultaneously block rail shipments of LNG would be far more difficult
to execute successfully. The effectiveness of LNG backup supplies could be limited, however,
due to the time required for rail deliveries, the scale of rail equipment to handle the required LNG
volumes, and the ability of end users to access such supplies.

16 A related issue of debate is the potential environmental impact of greenhouse gas emissions from natural gas
production and transportation prior to rail shipment and from natural gas combustion by consumers. Analysis of this
issue is outside the scope of this report.
17 See, for example: Institute for the Analysis of Global Security (IAGS), The Terrorist Threat to Liquefied Natural
Gas: Fact or Fiction?, February 2008; Government Accountability Office (GAO), Maritime Security: Public Safety
Consequences of a Terrorist Attack on a Tanker Carrying Liquefied Natural Gas Need Clarification, GAO-07-316,
February 2007; Jerry Havens, “Terrorism: Ready to Blow?,” Bulletin of the Atomic Scientists, July/August 2003, p. 17.
18 See, for example, Representative Peter DeFazio, “Amendment No. 233 Offered by Mr. DeFazio,” floor debate,
Congressional Record, daily edition, vol. 165, June 24, 2019, p. 106.
19 Volpe Center, U.S Department of Transportation, “Transportation Study: Impacts Associated with New and
Emerging Natural Gas Liquefaction Facilities,” white paper, January 2016, p. 23, https://rosap.ntl.bts.gov/view/dot/
36455/dot_36455_DS1.pdf.
20 Government Accountability Office, Critical Infrastructure Protection: Actions Needed to Address Significant
Weaknesses in TSA’s Pipeline Security Program Management, GAO-19-48, December 2018.
21 For further discussion of pipeline security, see CRS Insight IN11060, Pipeline Security: Homeland Security Issues in
the 116th Congress, by Paul W. Parfomak.
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Federal Agency Roles
Several federal agencies are involved with the safety and security regulation of LNG shipments
by rail. U.S. regulation applies to any train operating in the United States, regardless of its origin
or destination. In addition, the rail industry establishes its own consensus standards, discussed
later in this report.
Federal Railroad Administration
The Federal Railroad Administration (FRA), an agency within the Department of Transportation
(DOT), has jurisdiction over U.S. railroad safety. FRA has about 370 federal inspectors
throughout the country and also utilizes about 170 state railroad safety inspectors.22 State
inspectors predominantly enforce federal requirements because federal rail safety law preempts
state law. FRA uses past incident data to determine where its inspection activity should be
targeted. FRA regulations cover the safety of track, grade crossings, rail equipment, operating
practices, and movement of hazardous materials (hazmat).
Pipeline and Hazardous Materials Safety Administration
PHMSA, also within DOT, issues regulatory requirements for the safe transport of hazmat,
including LNG, by all modes of transportation.23 FRA enforces PHMSA’s hazmat regulations
with respect to railroads.24 FRA and PHMSA work together on rail hazmat safety but FRA’s core
focus is with train operations while PHMSA’s core focus is on hazmat packaging requirements,
such as the design of tanks used in LNG transportation. PHMSA also regulates the safety and
security of certain LNG facilities which may be involved in rail transportation.25
National Transportation Safety Board
Rail incidents are investigated by the National Transportation Safety Board (NTSB), an
independent federal agency. Although it has no regulatory authority, the NTSB makes
recommendations to regulatory agencies toward preventing future incidents, based on its findings.
The NTSB typically recommends specific regulatory changes based on the findings of its
accident investigations, but may also prepare safety studies and special reports, and convene
public forums, about safety issues on its own initiative.26 Agencies such as FRA and PHMSA do
not always agree with the NTSB’s recommendations. If they choose to implement them, they
normally must first go through a rulemaking process which involves consultation with industry
advisory committees, public comment, and approval from the Office of Management and Budget.

22 FRA, “Office of Railroad Safety,” October 31, 2019, https://railroads.dot.gov/about-fra/program-offices/office-
railroad-safety.
23 Through its Office of Pipeline Safety, PHMSA also sets and enforces safety standards for onshore natural gas
pipelines and LNG facilities, including facilities for the production, storage, and transfer of LNG (49 C.F.R. §193).
PHMSA works in partnership with state agencies to ensure that regulated LNG facility operators comply.
24 DOT has the emergency authority to restrict or prohibit transportation that poses a hazard of death, personal injury,
or significant harm to the environment. See 49 U.S.C. §20104.
25 49 C.F.R. §193.
26 For rail examples, see NTSB, Special Investigation Report on Railroad and Rail Transit Roadway Worker
Protection, NTSB Number SIR-14-03, September 24, 2014; and “NTSB Holds Forum on Safety of Rail Transportation
of Crude Oil and Ethanol,” press release, April 21, 2014.
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Transportation Security Administration
Under the Aviation and Transportation Security Act (P.L. 107-71) and the Homeland Security Act
of 2002 (P.L. 107-296), the Transportation Security Administration (TSA) within the Department
of Homeland Security (DHS) is responsible for securing freight rail transportation. However,
Section 1711 of the Homeland Security Act also gives DOT statutory authority to “prescribe
regulations for the ... security, of hazardous material in intrastate, interstate, and foreign
commerce,” which would encompass LNG by rail. Presidential Policy Directive (PPD) 21
designates DOT and DHS as Co-Sector-Specific Agencies for Transportation Systems.27
Under PPD-21, issued in 2013, a sector-specific agency is responsible for “providing institutional
knowledge and specialized expertise as well as leading, facilitating, or supporting the security and
resilience programs and associated activities of its designated critical infrastructure sector in the
all-hazards environment.”28 Within DHS these responsibilities are carried out by TSA, working
jointly with PHMSA. TSA has developed a Transportation Sector-Specific Plan for freight rail
security and is authorized to impose security directives, if needed, which have the force of
regulations.29 PHMSA has promulgated regulations for the security of hazmat shipments by rail,
including a requirement for security plans, which are enforced by FRA.30
Other Federal Agencies
The Federal Energy Regulatory Commission, an independent agency, has siting authority under
the Natural Gas Act over interstate natural gas pipelines as well as the place of entry and exit,
siting, construction, and operation of LNG terminals used for interstate commerce, import, or
export.31 Some facilities producing, storing, or accepting LNG transported by rail could fall under
the commission’s jurisdiction. Department of Energy has authority under the Natural Gas Act to
authorize the export of LNG to foreign buyers. Potential LNG exporters must file for an export
authorization under the rules and procedures established by the department.32 Therefore,
shipments of LNG for export require its approval before leaving the United States. For
applications to export LNG to countries with which the United States does not have a free trade
agreement, the Department of Energy considers economic impacts, security of natural gas supply,
and environmental impacts, among other factors.33 The Coast Guard has jurisdiction over the
safety and security of waterfront facilities supporting maritime commerce. Thus, if shipments of
LNG by rail were to originate or terminate at a port facility, the Coast Guard would have
jurisdiction over the rail operations occurring on port grounds.

27 Executive Office of the President, “Presidential Policy Directive—Critical Infrastructure Security and Resilience,”
PPD-21, February 12, 2013.
28 PPD-21; Sector-specific agencies’ responsibilities are further elaborated in Department of Homeland Security, NIPP
2013: Partnering for Critical Infrastructure Security and Resilience, 2013, Appendix B.
29 Transportation Security Administration, Transportation Systems Critical Infrastructure and Key Resources Sector-
Specific, Plan-Freight Rail Modal Annex, May 2007.
30 49 C.F.R. §§172.800 et seq.
31 15 U.S.C. §§717 et seq.
32 15 U.S.C. §717b(a); DOE regulations implementing those requirements were promulgated at 10 C.F.R. Part 590,
“Administrative Procedures with Respect to the Import and Export of Natural Gas.”
33 Department of Energy, Office of Fossil Energy, “Policy Statement Regarding Long-Term Authorizations to Export
Natural Gas to Non-Free Trade Agreement Countries,” 83 Federal Register 28841-28843, June 21, 2018. For further
background, see CRS Report R45006, U.S. Liquefied Natural Gas (LNG) Exports: Prospects for the Caribbean, by
Michael Ratner et al.
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Federal Approval of LNG by Rail
Prior to PHMSA’s final rule for LNG-by-rail, federal hazardous materials regulations prohibited
rail shipment of LNG except with either FRA approval or a PHMSA special permit.34 FRA could
allow LNG shipments in specialized, multi-modal tank containers of the type already approved
for transporting LNG in general commerce (i.e., by truck or container ship). These intermodal
tank containers had previously been approved by PHMSA. Built to specifications set by the
International Organization for Standardization (ISO), they are commonly referred to as ISO
containers.35 A special permit from PHMSA was required to transport LNG in rail tank cars
because such cars were not authorized to carry LNG. Shippers with a special permit from
PHMSA to ship LNG in rail tank cars would not require separate FRA approval because the
agencies cooperate in reviewing such permit applications.
FRA granted its first LNG-by-rail approval in 2015 to the Alaska Railroad Corporation, which
has subsequently transported LNG in ISO tank containers (Figure 1) from Anchorage to
Fairbanks.36 FRA issued a second such approval in 2017 to the Florida East Coast Railroad,
which is using LNG as a locomotive fuel and is testing LNG transport in ISO tank containers
from Jacksonville to Miami, possibly for export to locations in the Caribbean.37
Figure 1. Alaska LNG Shipment on Flatbed Rail Cars in ISO Containers

Source: Federal Railroad Administration, Office of Technical Oversight,

34 Hazmat regulations are at 49 C.F.R. §172 et seq. PHMSA special permits are authorized under 49 U.S.C. §5117;
special permits may be issued to any applicant performing a regulated function, including, a “person who—(i)
transports hazardous material in commerce; (ii) causes hazardous material to be transported in commerce; (iii) designs,
manufactures, fabricates, inspects, marks, maintains, reconditions, repairs, or tests a package, container, or packaging
component that is represented, marked, certified, or sold as qualified for use in transporting hazardous material in
commerce; (iv) prepares or accepts hazardous material for transportation in commerce; (v) is responsible for the safety
of transporting hazardous material in commerce” (49 U.S. Code § 5103(b)(1)(A)). FRA approval is authorized under 49
C.F.R. §174.63 and applies to any “carrier,” defined as “a person who transports passengers or property in commerce
by rail car, aircraft, motor vehicle, or vessel” (49 C.F.R. §171.8).
35 49 C.F.R. §178.274.
36 Alaska Railroad Corp., “Stars Align for LNG-Haul Demo This Fall,” All Aboard, newsletter, Second Quarter 2016,
at https://insidetrack.akrr.com/web/NEWS/AllAboard/2016_2Qtr_AllAboard.pdf.
37 PHMSA, Risk Assessment of Surface Transport of Liquid Natural Gas, March 20, 2019, p. 23.
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In January 2017, the Association of American Railroads, a trade group, petitioned DOT to allow
LNG to be transported in certain rail tank cars (the DOT-113 design) nationwide.38 These rail tank
cars can carry about three times more LNG than an ISO tank container. The association sought
the change for LNG because, according to its petition, “it is a safe method of transporting this
commodity, LNG shippers have indicated a desire to use rail to transport it, and because railroads
potentially will need to transport LNG for their own use as a locomotive fuel.”39
In August 2017, Energy Transport Solutions (ETS), a prospective LNG shipper, applied to DOT
for a special permit to transport LNG in DOT-113 rail tank cars between three points of origin
and three destinations “in LNG trains that consist of 20 or more tank cars in a continuous block
on a single train or 35 or more tank cars across an entire train.”40 On December 5, 2019, PHMSA
issued this special permit, authorizing ETS to transport LNG only between Wyalusing, PA, and
Gibbstown, NJ, in DOT-113C120 tank cars with no intermediate stops and subject to certain
operational controls.41 The permit does not specify a particular route. The ETS special permit and
tank car specification are further discussed later in this report.
Executive Order 13868
On April 10, 2019, the Trump Administration issued Executive Order 13868, Promoting Energy
Infrastructure and Economic Growth, with the stated purpose of enabling “the timely
construction of the infrastructure needed to move our energy resources through domestic and
international commerce.” 42 Among other provisions, the order states
The Secretary of Transportation shall propose for notice and comment a rule, no later than
100 days after the date of this order, that would treat LNG the same as other cryogenic
liquids and permit LNG to be transported in approved rail tank cars. The Secretary shall
finalize such rulemaking no later than 13 months after the date of this order.43
Based on the date of the order, issuance of the final rule was required by May 10, 2020. PHMSA
forwarded the rule to the Office of Management and Budget for review on April 30, 2020.44
PHMSA issued the final rule on June 19, 2020. The rule was published in the Federal Register on
July 24, 2020, with an effective date of August 24, 2020.

38 Petition requirements are found at 49 C.F.R. §§106.95-106.105.
39 Association of American Railroads, “Petition for Rulemaking to Allow Methane, Refrigerated Liquid to Be
Transported in Rail Tank Cars,” before the Pipeline and Hazardous Materials Safety Administration, P-1697, January
17, 2017, p. 1. The use of LNG as a fuel for rail locomotives also involves LNG movement by rail, but in relatively
limited quantities for consumption by the locomotives themselves.
40 Energy Transport Solutions, “Application for a Special Permit, to Transport Methane, Refrigerated Liquid, in DOT
113 Tank Cars,” before the Department of Transportation, Research and Special Programs Administration, August 21,
2017, p. 3. The names of the points of origin and destinations were redacted from the application as confidential
business information.
41 PHMSA, Special Permit DOT-SP 20534, granted to Energy Transport Solutions, LLC, December 5, 2019, at
https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/docs/safe-transportation-energy-products/72906/dot-20534.pdf.
42 Executive Order 13868, “Promoting Energy Infrastructure and Economic Growth,” 84 Federal Register 72, April 14,
2019, p. 15495. The order was issued on April 10, 2019.
43 84 Federal Register 15497.
44 Office of Management and Budget, online regulatory database, accessed May 11, 2020, https://www.reginfo.gov/
public/do/eoDetails?rrid=130458.
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PHMSA LNG by Rail Rulemaking
In response to Executive Order and the AAR petition, on October 24, 2019, PHMSA published in
the Federal Register a Notice of Proposed Rulemaking (NPRM) for public comment on potential
changes to its hazmat regulations to authorize LNG transportation by rail throughout the U.S. rail
network in a specific type of DOT-113 rail tank car.45 In its NPRM, the agency stated that growth
in domestic LNG production capacity “has led to significant challenges in the transportation
system” and, therefore, that “there may be a demand for greater flexibility in the modes of
transportation available to transport LNG.” The NPRM further stated that “some shippers have
expressed that there is an interest in the transportation of LNG by rail (domestically and for
international export), which would help address these challenges.”46 The comment period, after
extension, closed on January 13, 2020.47 The NPRM drew comments in support and opposition to
it, including submissions from other federal agencies.
PHMSA’s proposed rule sought to allow LNG to be carried in DOT-113C120W specification
tank cars (Figure 2), which are designed to carry liquefied ethylene, “another flammable
cryogenic liquid which shares similar chemical and operating characteristics with LNG.”48 In
PHMSA’s rulemaking, the agency, in conjunction with FRA, examined potential limitations for
routes and train length specifically for LNG shipments in rail tank cars. Speed restrictions and
requirements that cars be equipped with specialized brakes (further discussed below) were also
under consideration. While the proposed rule did not discuss specific tank car features designed
to reduce the chances of tank car punctures during derailment, such as those newly required of
cars carrying crude oil, the final rule requires a thicker tank shell.
Figure 2. Insulated Rail Tank Cars Proposed for LNG

Source: Chart Industries.

45 This is the rail car approved for use in the PA-NJ route mentioned above. PHMSA, “Hazardous Materials: Liquefied
Natural Gas by Rail.” Notice of Proposed Rulemaking (NPRM) at 84 Federal Register 56964-56977, October 24,
2019. (Hereinafter PHMSA NPRM.)
46 Ibid, p. 56965.
47 84 Federal Register 70491, December 23, 2019.
48 PHMSA NPRM, p. 56967.
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Selected Policy Issues
The federal government’s issuance of the PHMSA rulemaking and its approvals of LNG
shipments by rail have drawn both support and criticism. Consistent with the AAR’s initial
petition for PHMSA to allow LNG by rail, the association and other industry groups also support
the broader rule. However, the NTSB, as well as a coalition of state attorneys general,
environmental groups, and other groups, have expressed opposition. The following sections
discuss selected issues raised during the rulemaking process.
Safety of Unit vs. Manifest Trains
An important safety aspect of the final rule is how much LNG by rail would be carried in unit
trains versus manifest trains. A manifest train carries a varied mix of products, usually in various
different car types (e.g., box car, flatbed, tank car). A unit train comprises just one car type
carrying a single commodity to a single destination, usually returning empty to its point of origin.
Ethanol was the first hazardous material to be carried in unit versus manifest train formations in
the United States, commencing in 2003.49 Shipment of crude oil in unit trains grew significantly
during the 2010s.50
PHMSA’s final environmental assessment for the ETS special permit states that the applicant
“seeks authorization to ship LNG via rail ... in shipment configurations that could range from
single to multiple tank cars (blocks) in general manifest trains ... up to dedicated train
configurations consisting of up to 100 tank cars (unit train).”51 The assessment further evaluates a
“baseline case” in which ETS would ship between two and four unit trains of LNG per day.52 In
its NPRM, the agency stated
While PHMSA expects LNG will initially move in smaller quantities (i.e., a few tank cars)
as part of manifest trains, it is uncertain whether LNG will continue to be transported in
those quantities or if LNG by rail will shift to be transported using a unit train model of
service, and if so, how quickly that shift will occur.53
Likewise, PHMSA’s final rule states
PHMSA cannot predict the number of DOT-113C120W9 tank cars per train the LNG
market will support, but we know that from ETS’s application for DOT-SP 20534, that it
has plans to operate unit trains of at least 80 cars per train at some point in the future.54
Therefore, while PHMSA’s final rule does not predict future numbers of LNG unit train
shipments, it would allow them. The agency asserts, however, that the “likelihood is low that
there will be LNG unit trains, at least initially” due to the associated requirements for

49 Burlington Northern and Santa Fe Railway Company, “BNSF Moves 10,000th Carload of Ethanol Through BNSF
Ethanol Express Unit Train Service,” press release, September 28, 2004. Typically, ethanol is carried either in a unit
train, or in a manifest train with numerous continuous cars carrying ethanol.
50 For further discussion of crude oil shipment by rail, see CRS In Focus IF10727, Rail Transportation of Crude Oil
and the FAST Act: An Update, by John Frittelli.
51 PHMSA, SP 20534 Special Permit to Transport LNG by Rail in DOT113C120W Rail Tank Cars, Final
Environmental Assessment, Docket No. PHMSA-2019-0100, December 5, 2019, p. 3.
52 Ibid., p. 23.
53 PHMSA NPRM, p. 56969.
54 PHMSA Final Rule, p. 45005.
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infrastructure, tank cars, planning, and financial investment.55 Whether LNG is carried in a
manifest or unit train configuration has risk implications because of the placement of the cars
relative to the location of crews and possible flaws in the tracks, discussed below.
Derailment Risks and Safety Measures
According to the Association of American Railroads, 99.999% of all hazmat railcars reach their
destinations without an incident that releases product; in 2016, the number of train accidents with
a hazmat product release was 0.69 for every 100,000 hazmat carloads.56 Hazmat rail accidents not
involving a release occur more frequently. Derailment is the primary type of rail accident, in
general, accounting for over two-thirds (1,285) of all U.S. train accidents in 2019.57 Over the last
decade, derailment has been identified as the cause of several major hazmat rail accidents.58
A leading cause of derailments is a flaw in a steel rail. The locomotive and first few cars may
successfully pass over this flaw, but their weight and the forces involved could exacerbate the
flaw and cause a rail break. Succeeding cars passing over that point in the track would derail, at
which time the emergency brakes would be applied. Before the last cars in the train pass over the
rail break, the train could be significantly slowed or come to a stop. The first and last cars in the
train, therefore, might avoid derailment or derail at a much slower speed.59
To reduce hazmat derailment risks, cars carrying hazmat in a manifest train can be placed either
toward the rear or the front of the train. However, these configurations increase the likelihood that
hazmat would be released if another train collides with the manifest train from the rear or if the
manifest train itself collides with a train ahead. Such an incident could release hazmat closer to
the train operators located at the front of a train. The NTSB has recommended that at least five
“buffer” cars carrying non-hazardous material separate the head locomotive with train crew from
the nearest hazmat car, but FRA has not adopted this recommendation.60 An alternative is to
surround a rail car carrying a flammable or otherwise hazardous product with cars carrying non-
hazardous material. If that group of cars should derail, a fire or explosion due to release of
material from the hazmat car would be less likely to trigger fires or explosions in the non-hazmat
derailed cars nearby. Other relevant factors to consider in arranging the configuration of a train is
the relative weight of individual cars, which affects train control, and whether the placement
would require more switching in rail yards, which may pose other risks.
In a loaded unit train, any derailed cars will be carrying the hazardous material. Given some of
the large fires and explosions that have occurred when crude oil and ethanol unit trains have
derailed in the past,61 DOT has mandated a number of specific measures for these trains to reduce

55 PHMSA Final Rule, p. 45009.
56 Association of American Railroads, “Railroads Safely Deliver Hazardous Materials,” accessed May 12, 2020,
https://www.aar.org/data/railroads-safely-deliver-hazardous-materials/.
57 Federal Railroad Administration, “Total Accidents/Incidents, Jan–Dec,” online database, April 29, 2020,
https://safetydata.fra.dot.gov/officeofsafety/publicsite/summary.aspx.
58 See, for example, National Transportation Safety Board, Derailment of CN Freight Train U70691-18 with
Subsequent Hazardous Materials Release and Fire, Cherry Valley, Illinois, June 19, 2009, NTSB/RAR-12/01,
February 14, 2012; and Derailment and Hazardous Materials Release of Union Pacific Railroad Unit Ethanol Train,
Graettinger, Iowa, March 10, 2018, NTSB/RAR-18/02, October 30, 2018.
59 This occurred, for example, in the 2018 Union Pacific ethanol train derailment. Ibid.
60 National Transportation Safety Board, “2019–2020 NTSB Most Wanted List of Transportation Safety
Improvements: Ensure the Safe Shipment of Hazardous Materials,” fact sheet, 2019, at https://www.ntsb.gov/safety/
mwl/Documents/2019-20/2019-20-MWL10-HazMat-R.pdf.
61 National Transportation Safety Board, October 30, 2018; Transportation Safety Board of Canada, Runaway and
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the chances of derailment and mitigate the consequences of a derailment. Most of these measures
were not proposed as requirements in PHMSA’s LNG-by-rail rulemaking, however PHMSA did
include several of the measures in its final rule, as further discussed below.
Cascading Failure
FRA has stated in past regulatory correspondence that “the transportation of large quantities of
LNG in a single train presents unique safety risks.”62 Stakeholders have identified the potential
for “cascading failure” as one of these risks. In this kind of event, an uncontrolled LNG release
and fire from one failed tank would cause successive cars to fail due to heat exposure, thereby
increasing the overall quantity of LNG released in the incident. Such failures have occurred in rail
accidents involving shipments of crude oil and ethanol.63
PHMSA’s NPRM discussed the possibility of cascading failure in an accident involving LNG
tank cars. The NPRM concluded that, due to the design of the DOT-113 tank cars “the risk of tank
car failure and ignition” due to heat exposure “is low.”64 The NPRM stated that the “special
design of the DOT-113 tank car reduces the probability of cascading failures of other undamaged
DOT-113 specification tank cars being transported in a block or unit train configuration.” It
further stated that exposure to heat or cryogenic temperature from a damaged LNG tank car
“could potentially lead to the release of material or failure of otherwise undamaged tank cars,”
but “an undamaged DOT-113 specification tank car exposed to a radiant heat source could
eventually ... trigger the activation of the tank car’s [pressure release device]” which “would
result in the controlled venting of LNG vapor” creating a significant risk of fire.65 Related to this
issue, FRA conducted fire safety tests in 2017 demonstrating that the pressure relief devices on a
multi-modal ISO container (filled with nitrogen), which are similar in design to those on a DOT-
113 tank car, worked as expected.66 The NPRM also cited AAR Circular OT-55 provisions related
to unit trains as sufficient for addressing the safety risks of LNG unit train shipments.67 The
proposed rule, therefore, did not propose additional restrictions on the number of tank cars
carrying LNG in one train. After reviewing comments on its NPRM related to a potential limit to
the maximum weight or length for trains carrying LNG, PHMSA reasserted in its final rule that
“that there should not be a maximum for either,” and that “train length is best determined by
individual railroads.”68
PHMSA’s assertion in its NPRM that the design of DOT-113 tank cars makes it safe to carry
LNG in configurations of multiple tank cars, including unit trains, has been disputed. In

Main-Track Derailment, Montreal, Maine and Atlantic Railway Freight Train MMA-002 Mile 0.23, Sherbrooke
Subdivision Lac-Mégantic, Quebec, Report R13D0054, July 6, 2013.
62 Karl Alexy, Federal Railroad Administration, Letter to James R. Hertwig, Florida East Coast Railway, March 3,
2016, p. 2. Available as “Exhibit D” at https://www.regulations.gov/document?D=PHMSA-2019-0100-2763, p. 1.
63 See, for example NTSB, “Railroad Accident Brief: Norfolk Southern Railway Company Train Derailment and
Hazardous Materials Release,” NTSB/RAB-14/08, September 18, 2014.
64 PHMSA NPRM, p. 56974.
65 Ibid.
66 The FRA has reported the results of a fire safety tests conducted in 2017 on a multi-modal tank container filled with
liquid nitrogen (a non-flammable cryogenic liquid) loaded on a rail flat car over a propane pool fire to evaluate the
pressure relief valves. In the tests, the relief valve system successfully vented the evaporating nitrogen before the
pressure became high enough for a BLEVE to occur (tank failure). See FRA, Fire Performance of a UN-T75 Portable
Tank Phase 1: Loaded with Liquid Nitrogen, DOT/FRA/ORD-20/02, January 2020.
67 PHMSA NPRM, p. 56973.
68 PHMSA Final Rule, p. 45018.
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particular, critics have questioned PHMSA’s conclusions regarding the risk of cascading failures
in an accident involving unit trains.69 FRA is conducting additional rail safety testing of
multimodal ISO tank containers filled with LNG, but has not yet reported results.70 With limited
domestic experience of LNG-by-rail shipments in multiple car configurations, the risk
implications of increasing the number of LNG cars in a shipment may continue to be the subject
of disagreement.71
Reducing the chances of derailment requires more frequent track and rolling stock inspections.
Reducing the consequences of a derailment—including cascading failure—involves the
crashworthiness of tank car design standards, braking systems, train speed, routing analysis, and
the preparedness of emergency responders. While the proposed rulemaking mentioned AAR
Circular OT-55, the industry safety standard for trains carrying 20 or more cars of hazardous
material (referred to by the rail industry as “key trains”), it did not propose to incorporate these
standards into the rulemaking.72 Circular OT-55, among other things, limits the speed of key
trains to 50 miles per hour and specifies the frequency of inspections of tracks and rail cars
supporting their movement. In its final rule, PHMSA reasserts that “the operational control
recommendations in AAR Circular OT–55 address safety concerns related to train movements of
hazardous materials comprehensively” and that “railroads are implementing and following
Circular OT–55 through their operating rules.”73 However, the agency also “acknowledges the
concerns about relying on a widely adopted, voluntary industry standard, rather than imposing
regulatory requirements.”74
Tank Car Safety Design and Safety Record
In a derailment, the forces applied as rail cars ram into one another (or into a significant fixed
structure along the track) are so great that it is impracticable to build a tank car that is puncture
proof in these scenarios. The strategy, instead, has been to reduce the number of cars being
punctured with practical design elements.
Safety design elements for rail tank cars include increasing the metal thickness of the outer tank
shell (adding a jacket layer) or adding metal protective shields to parts of the tank car most
exposed to ramming by another car. The DOT-113C120W tank car mandated in PHMSA’s
proposed rule is essentially designed like a thermos bottle to keep the LNG at the required
cryogenic temperature. The tank car has a vacuum-insulated inner container (tank) enclosed
within an outer shell. The inner tank is ¼-inch stainless steel and the outer tank is 7/16-inch
carbon steel.

69 See, for example, Earthjustice, “RE: Comments Objecting to the Proposed Rulemaking to Authorize the
Transportation of Methane, Refrigerated Liquid by Rail, Docket No. PHMSA‐ 2018‐0025 (HM‐264), letter to PHMSA,
January 13, 2020, p. 15; Representative Peter Defazio, “Amendment No. 233 Offered by Mr. DeFazio,” floor debate,
Congressional Record, daily edition, vol. 165, June 24, 2019.
70 PHMSA, Hazardous Materials: Liquefied Natural Gas by Rail, Notice of Proposed Rulemaking, Preliminary
Regulatory Impact Analysis, Docket No. PHMSA-2018-0025 (HM-264), RIN 2137-AF40, October 2019, p. 13.
71 Japanese operators began shipping LNG by rail (in ISO containers) in 2000. Other countries, such as Germany, have
since begun LNG rail shipments as well. However, differences in infrastructure and regulation may limit the
applicability of foreign country experiences to the United States. See Ryosuke Hanafusa, “Transporting Natural Gas by
Train: The Greener Way to Go,” Nikkei Asian Review, March 16, 2018; VTG Aktiengesellschaft, “European Premiere:
First LNG Tank Car Loading,” press release, April 24, 2016.
72 AAR Circular OT-55, at https://public.railinc.com/sites/default/files/documents/OT-55.pdf.
73 PHMSA Final Rule, p. 45018.
74 PHMSA Final Rule, p. 45019.
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In addition to increasing the shell thickness of the DOT-113 tank car, several other design features
relevant to puncture resistance may be considered for further improvement. Car couplers, which
are the devices used to connect rail cars together, can often act as ramming devices for a
neighboring car, with more frequent punctures at the head or rear of the tank. The “double-shelf”
coupler, required for tank cars carrying hazmat, is designed to reduce the chances of cars
becoming decoupled in a derailment. Valve openings and/or housings, where product is loaded or
unloaded from the tank car, may also be reinforced so that they do not shear off during a
derailment. Tank car thermal insulation is also a critical design element, affecting heat absorption
from a neighboring derailed car that is on fire. Pressure relief valves, particularly their capacity,
also have been redesigned so that pressure which may build up in an un-punctured derailed car
(e.g., due to external heat) can be released, preventing or delaying an explosion. Relatedly,
regulations can specify how much product can be loaded into a tank car, which also affects
internal tank pressure. Pressure relief valves and insulation can provide more time for emergency
responders to move intact cars away from any that are on fire. PHMSA has required
enhancements to these design elements for tank cars carrying crude oil and ethanol in unit train
formations.75
PHMSA’s proposed rule would have allowed the existing DOT-113 tank car design to be used for
LNG. The existing fleet of DOT-113 tank cars consists of 405 cars and most of them are used to
carry a non-flammable material (refrigerated carbon dioxide). Fewer than 3% of shipments using
DOT-113 tank cars carry a flammable material (refrigerated ethylene).76 The NTSB therefore has
contended that the derailment experience with DOT-113 tank cars carrying flammable gases is
too limited to draw conclusions about the robustness of the design for LNG. Consequently, the
NTSB recommended that DOT perform a comprehensive review of the crashworthiness and
puncture resistance of the DOT-113 tank car at different speeds.77 In November 2019, DOT
performed a test simulating a railcar coupler ramming a DOT-113 tank car positioned
perpendicularly against a fixed structure. Moving at about 17 mph, the ramming device punctured
both walls of the DOT-113 tank car.78
The Railroad Tank Car Committee
The Railroad Tank Car Committee (TCC) is a long-standing industry group which evaluates and
sets industry standards for tank car designs.79 Its members represent railroads, tank car leasing
companies, and shippers (rail customers, such as chemical or petroleum companies that own the
cargo). Under the Hazardous Materials Transportation Act (P.L. 93-933) and DOT regulations, the

75 The enhancements distinguish the older DOT-111 tank car design from the newer DOT-117 design (49 C.F.R.
§179.202-12) for carrying crude oil and ethanol.
76 Association of American Railroads, “Petition for Rulemaking to Allow Methane, Refrigerated Liquid to Be
Transported in Rail Tank Cars,” before the Pipeline and Hazardous Materials Safety Administration, P-1697, January
17, 2017, p. 3. National Transportation Safety Board, letter submission to the U.S. Department of Transportation,
Docket No. PHMSA–2018–0025 (HM–264), December 5, 2019, p.3.
77 National Transportation Safety Board, letter submission to the U.S. Department of Transportation, Docket No.
PHMSA–2018–0025 (HM–264), December 5, 2019, p.3.
78 Federal Railroad Administration, “Full-Scale Shell Impact Test of a DOT-113 Tank Car,” February 2020, at
https://railroads.dot.gov/sites/fra.dot.gov/files/2020-02/Full-Scale%20Impact%20Test%20DOT-
113%20Tank%20Car.pdf.
79 Rail cars often traverse the track of more than one railroad. Therefore, industry has needed to set design standards for
many rail car components to ensure interoperability; for instance, general elements like axle width and coupler height,
and very detailed car specifications. These design standards enable railroads to maintain and repair cars interchanged
among them.
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TCC has authority to review the “designs, materials and construction, conversion or alteration of
tank car tanks” and to review “proposed changes in or additions to specifications for tanks.”80 The
TCC may make recommendations for DOT to consider, although it has no authority, itself, to
regulate tank car specifications. Thus, the DOT relies on the TCC in an advisory capacity with
respect to regulating tank cars. The TCC was evaluating the DOT-113 tank car design and was
expected to provide its recommendation on any safety design improvements to DOT in the
summer of 2020, but an April 2020 meeting of the committee was canceled due to the COVID-19
outbreak.81
Most often, in the tank car segment, shippers rather than the railroads either own or lease the tank
cars from tank car leasing companies. Since rail shippers provide the tank cars while railroads
provide the track and train operations, there can be disagreement between railroads and tank car
shippers about how much emphasis should be placed on tank car safety versus track inspections
and train operating parameters.82 Railroads, which have the majority vote in the TCC, want to
increase the thickness of the outer shell of the DOT-113 tank car from 7/16 inch to 9/16 inch, the
same design change made for crude oil and ethanol tank cars (DOT-117 tank cars). Railroads also
seek more protective housing for the valves and fittings on the DOT-113 tank car.83 Tracks are
generally built for a maximum gross rail car weight of 286,000 lbs. each, so shippers have
concern that increasing the empty weight of a rail car may significantly reduce the amount of
product that can be loaded. Notwithstanding these weight considerations, PHMSA’s final rule
requires DOT–113 tank cars carrying LNG to have a minimum outer tank thickness of 9/16 inch,
and further requires them to be made of a specialized, more puncture-resistant steel.84
Train Speed and Braking Systems
The extent of derailment and the probability of cars being punctured and releasing product also
relate to rail car speed at derailment and the braking time. For trains carrying ethanol, crude oil,
or any Class 3 flammable liquid, PHMSA regulations impose a speed limit of 50 miles per hour
for trains carrying 20 or more tank cars in a continuous block or 35 or more such cars anywhere
in the train (49 C.F.R. 174.310(a)(2)). Trains with this many tank cars of flammable liquid are
referred to in the regulations as Highly Hazardous Flammable Trains (HHFT). The speed limit is
reduced to 40 miles per hour if any of the tank cars are of an older, less safe design and the train
is traveling through certain urban areas (High Threat Urban Areas listed in Appendix A to 49
C.F.R. Part 1580). Because LNG is categorized in Class 2.1, as a flammable gas, and not in Class
3, as a flammable liquid, LNG trains would not fall under the HHFT operating rules. The NTSB
recommended that these speed limits be applicable to trains carrying LNG as the NPRM does not
propose mandating a speed limit. Railroads have expressed concern that adding trains carrying
LNG at reduced speed could further reduce the capacity of their entire networks.

80 49. C.F.R. §§179.3-179.4. In addition to defining this “delegated authority,” §179 refers to the TCC’s specifications
for tank cars in discussing more detailed aspects of tank car design in over 60 subparts of the code.
81 Comments of the Association of American Railroads (AAR) and the American Short Line and Regional Railroad
Association (ASLRRA) submitted to DOT, Docket No. PHMSA–2018–0025 (HM–264), “Notice of Proposed
Rulemaking (NPRM) to Authorize the Transportation of Liquefied Natural Gas by Rail Tank Car,” December 19,
2019, https://www.regulations.gov/document?D=PHMSA-2018-0025-0112.
82 Thompson Hine LLP, Counsel for Petitioners American Chemistry Council, et al., Petition to Amend Relating to
Tank Car Standards, August 12, 2016, PHMSA petition no. P-1678, Docket no. PHMSA-2016-0093, August 12, 2016,
https://www.regulations.gov/searchResults?rpp=25&po=0&s=PHMSA-2016-0093&fp=true&ns=true.
83 AAR and ASLRRA, December 19, 2019.
84 PHMSA NPRM, p. 45004.
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Applying emergency brakes can cause derailment of cars even without a fault in the rails or a
defect in the cars. The braking signal travels from the locomotive to the following rail cars
sequentially and will take a few seconds to reach the last car. The rear-most cars, therefore, push
on cars in front that already have their brakes applied. To reduce the time required for the braking
signal to reach all cars, a second signal device or another locomotive at the end of the train can
almost simultaneously begin signaling braking forward.85 Rear-end train brake signaling is
currently required by federal regulation for HHFT trains but the NPRM did not propose it for
LNG trains. However, PHMSA’s final rule requires any train carrying 20 or more loaded tank
cars of LNG in a continuous block (or 35 or more loaded LNG tank cars throughout the train) to
have a two-way end-of-train device or employ multiple locomotives connected by radio and
positioned strategically to provide extra power and control for emergency braking.86
In addition to rear-end train brake signaling, debate continues on a 2015 PHMSA proposal (in
coordination with FRA) that cars carrying flammable liquids be required to have Electronically
Controlled Pneumatic (ECP) brakes, which can simultaneously signal all the cars to begin
braking.87 In 2015, Congress directed GAO to conduct an independent evaluation of ECP braking
systems.88 GAO raised questions about DOT’s methodology and the transparency of its data.89
After DOT conducted a revised cost benefit analysis in 2017, it found the benefits did not
outweigh the costs and withdrew the rulemaking.90 The NTSB recommended that DOT require
LNG trains either to use rear-end train brake signaling or require ECP brakes on the tank cars.91
PHMSA’s final rule does not include an ECP requirement, concluding that “ECP brakes are not a
practical alternative given that ECP brakes are not cost justified when applied to unit train
configurations in the [high-hazard flammable train] environment.”92
Track Quality and Routing Analysis
One means of mitigating the consequences of an LNG tank car derailment is to have trains
carrying these cars avoid densely populated areas or other risk-sensitive areas. Railroads
determine the routes over which they carry LNG. Some rail shippers may prioritize reliability of
delivery over speed of delivery. For these shippers, taking a more circuitous route for delivering
LNG, thereby avoiding populated areas, may still meet the needs of the customer. However, a
more circuitous route that avoids town or city centers would mean a longer journey both in terms
of time and distance, thereby increasing the overall likelihood of a safety incident. A more
circuitous routing also could mean use of less busy track that typically is of poorer quality and
less well maintained, which may have higher derailment rates.93

85 49 C.F.R. §§229.5 and 232.5.
86 PHMSA Final Rule, p. 45007.
87 80 Federal Register 26644, May 8, 2015.
88 FAST Act (P.L. 114-94) §7311.
89 GAO, DOT’s Rulemaking on Electronically Controlled Pneumatic Brakes Could Benefit from Additional Data and
Transparency, GAO-17-122, October 12, 2016.
90 82 Federal Register 58582, December 13, 2017.
91 National Transportation Safety Board (NTSB), letter submission to the U.S. Department of Transportation, Docket
No. PHMSA–2018–0025 (HM–264), December 5, 2019.
92 PHMSA FInal Rule, p. 45009.
93 Xiang Liu, M. Rapik Saat, and Christopher P.L. Barkan, “Freight Train Derailment Rates for Railroad Safety and
Risk Analysis,” Accident Analysis and Prevention, vol. 98, 2017, pp 1-9.
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As mentioned above, a leading cause of train derailments is defective rail. Much of the time these
defects are invisible fractures within the interior of a piece of rail. A secondary cause is rolling
stock defects such as a broken axle or wheel. Railroads have deployed detection technologies,
such as ultrasonic probes or acoustic and temperature sensors, intended to spot track and railcar
defects long before they can cause a derailment. Railroads also evaluate equipment failure history
and operational and environmental factors to pinpoint track segments and railcars that are at
higher risk and warrant more frequent inspection.94
In 2016 correspondence with the Florida East Coast Railway, the FRA discussed the
“complexity” and safety issues involved with shipping LNG on routes that “traverse congested,
highly populated areas, with frequent highway-rail grade crossings” and share track with
passenger trains.95 As discussed earlier, the FRA ultimately approved LNG shipments on these
routes. Similarly, the challenge of trying to avoid urban areas in routing LNG shipments has
arisen for shipments by Energy Transport Solutions (ETS) under its special permit. While ETS
has not publicly disclosed its actual routing of LNG shipments, press reports suggest that these
shipments would likely be carried through Philadelphia and over the Delaware Bridge to New
Jersey due to the limited rail options for crossing the Delaware River in this region. This route
would traverse densely populated areas of the city and share the rail bridge and tracks also used
by NJ Transit for one of its commuter lines.96 Prior to reaching Philadelphia, ETS shipments
could pass through other populous communities in Pennsylvania, depending upon the route
chosen. Since Amtrak or commuter railroads may own or use some of these route segments,
freight trains could be restricted temporally (e.g., nighttime only) or require some other
accommodations for passenger trains.
After the September 11, 2001, terrorist attacks, Congress required railroads to perform a routing
analysis for identifying the safest and most secure routes for trains carrying explosives,
radioactive material, and toxic-by-inhalation products.97 The regulation lists 27 factors related to
the immediate environment of the route that the railroads must consider. Later, this also became a
requirement for HHFTs. The HHFT planning requirements include route selection based upon “a
safety and security risk assessment of the alternative routes” taking account of “the risk of a
catastrophic release from a shipment traveling along each route.”98 The NTSB has recommended
that PHSMA impose additional planning requirements for shipping LNG by rail, similar to those
required for HHFTs under the existing regulations.99 Consistent with this recommendation,
PHMSA’s final rule requires that each rail car of LNG be remotely monitored for pressure and
location and makes trains consisting of an LNG tank car subject to route planning and routing
analysis requirements.100

94 Track inspection regulations are codified at 49 C.F.R. §§213.231-213.241.
95 Karl Alexy, Federal Railroad Administration, Letter to James R. Hertwig, Florida East Coast Railway, March 3,
2016, p. 2. Available as “Exhibit D” at https://www.regulations.gov/document?D=PHMSA-2019-0100-2763.
96 Andrew Maykuth, “Federal Officials will let LNG be Shipped by Rail to Greenwich Township Port,” The
Philadeplphia Enquirer, December 10, 2019.
97 49 C.F.R. §172.820.
98 49 C.F.R. §172.820(d).
99 National Transportation Safety Board, letter submission to the U.S. Department of Transportation, Docket No.
PHMSA–2018–0025 (HM–264), December 5, 2019, p. 5.
100 PHMSA Final Rule, p. 45019.
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Emergency Response Capabilities
Another issue of concern in debates about LNG shipment by rail is whether local first responders
would have sufficient training and resources to manage an accident involving an LNG release.101
At a 2019 “town hall” meeting on LNG by rail emergency preparedness conducted by PHMSA
and the Federal Emergency Management Agency’s National Fire Academy, a “key question”
discussed was “what additional training is needed for local responders ... to be ready to address
potential LNG release challenges.”102 Although participants commented that “experienced”
emergency responders “deal with products with far greater potential hazardous results/impact”
than LNG on a daily basis, they also concluded that “first responders in communities through
which LNG is transported will require supplemental information and training that complements
current hazmat training.”103 Accordingly, the special permit PHMSA issued to ETS requires the
company to train emergency responders along the proposed shipping route in conformance with
National Fire Protection Association standards “including known hazards in emergencies
involving the release of LNG, and emergency response methods to address an incident involving
a train transporting LNG.”104
Some Members of Congress have expressed specific concerns about the ability of emergency
responders to deal with an LNG by rail accident, especially in smaller, rural communities.105
Likewise, in comments on PHMSA’s NPRM, the International Association of Fire Fighters
stated, “it is highly likely that only a few fire departments will have an adequate number of
sufficiently trained personnel to effectuate safe and efficient evacuations while simultaneously
mitigating or suppressing the hazards of the gas release or fire.”106 Given these concerns, training
and resources for emergency responders along LNG by rail routes may continue to be an issue.
Security of LNG Shipments
The security of hazardous cargo shipments by rail has been a long-standing issue of concern in
Congress and among homeland security analysts. A 2009 report from GAO states:
experts consider the U.S. rail system to be an attractive terrorist target because of its public
accessibility, long stretches of open and unattended track, and the difficulty of securing a
wide array of rail assets that are difficult to patrol. Further, an attack on the U.S. freight

101 See, for example, Jesse Roman, “LNG By Rail,” NFPA Journal, March 1, 2020.
102 PHMSA and U.S. Fire Administration, PHMSA/NFA Town Hall Meeting Report: Emergency Preparedness Issues
Related to Proposed LNG Transportation by Rail, November 18, 2019, p.8.
103 Ibid. pp. 8, 10. Such products include flammable liquefied gases (e.g., propane) and toxic inhalation hazards (e.g.
ammonia).
104 PHMSA, December 5, 2019, p. 3. See National Fire Protection Association (NFPA), Standard for Competence of
Responders to Hazardous Materials/Weapons of Mass Destruction Incidents, NFPA-472, 2018. NFPA is a non-profit,
membership organization which promotes fire safety consensus standards, research, training, and education.
105 Senators Ron Wyden and Jeffrey A. Merkley, Letter to Mr. Howard Elliot, PHMSA Administrator, January 14,
2020, p.1, at https://www.wyden.senate.gov/imo/media/doc/011420%20Wyden%20Merkley%20LNG%20Letter.pdf.
“Rural communities ... often lack adequate emergency response resources to address the types or large scale of
accidents that are possible when transporting bulk quantities of LNG by rail.”
106 International Association of Fire Fighters, December 23, 2019, letter to U.S. Department of Transportation, “RE:
Comments Pursuant to the Notice of Proposed Rule Making re: Changes to Hazardous Materials Regulations to Allow
Bulk Liquefied Natural Gas by Rail Tank Car,” Docket No. PHMSA-2018-0025 (HM-264), December 23, 2019, p. 3.
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rail system could lead to catastrophic loss of life because the system often traverses densely
populated urban areas carrying highly hazardous materials.107
As discussed earlier, PHMSA requires hazmat shippers to prepare and adhere to planning
requirements for transportation security. These requirements apply to multimodal tank and tank
car shipments of LNG, which are considered “a large bulk quantity of Division 2.1 material” as
defined under the federal hazmat classification system.108 Under these requirements, among other
things, transportation security plans for LNG shippers must include:
 an assessment of transportation security risks for shipments of the hazardous
materials, including risks associated with LNG-handling facilities;
 measures to confirm information provided by job applicants hired for positions
that involve access to and handling of the LNG;
 measures to prevent unauthorized access to the LNG, rail cars, or trains;
 measures to address the risks of LNG shipments en route from origin to
destination, including shipments stored incidental to movement; and
 identification of responsible senior management, staff security duties; security
staff notification; and a plan for training hazmat employees.109
In its final rule, PHMSA states that, “properly implemented security plans decrease the risk that a
shipment of hazardous material, including LNG, can be used in an attack against persons or
critical infrastructure within the United States.”110 TSA has promulgated additional security
regulations for shipments of certain other hazmat materials considered to be of particularly high
risk, such as documenting the chain of custody and control. These regulations do not apply to
shipments of LNG.111
Safety and Security of LNG Facilities
Local communities have expressed concerns about the safety and security of facilities being
developed to supply or transfer rail shipments of LNG, such as the ETS facility in Gibbstown,
NJ.112 PHMSA regulates the safety and security of certain facilities that may be used to supply,
store, load, or unload LNG in rail transportation.113 However, PHMSA has interpreted its
jurisdiction to apply only to an LNG facility if it “either receives from or delivers to” a pipeline
regulated by the agency, which may not cover all facilities serving LNG shipments by rail.114 The
agency’s LNG facility safety regulations cover facility design, construction, equipment,

107 Government Accountability Office, Freight Rail Security, GAO-09-243, April 2009, p. 2.
108 49 C.F.R §172.800(b)(3).
109 49 C.F.R §172.802.
110 PHMSA Final Rule, p. 45001.
111 49 C.F.R. §1580.107. Per 49 C.F.R. §1580.100, the regulations apply to a rail car containing more than 5,000
pounds of certain explosives, a tank car containing certain poisonous materials, or a rail car carrying certain quantities
of radioactive material.
112 See, for example, Karl Baker, “Energy Company Says It’s Bringing LNG Port to the Delaware River,” The News
Journal, March 2, 2019.
113 49. C.F.R. §193.2007 et seq. PHMSA regulations define “LNG facility” as “a pipeline facility that is used for
liquefying natural gas ... or transferring, storing, or vaporizing liquefied natural gas” and further define “pipeline
facility” to include “any equipment, facility, or building used in the transportation of gas” (§193.2007).
114 PHMSA, “Jurisdiction of LNG Plants,” January 31, 2018, at https://www.phmsa.dot.gov/pipeline/liquified-natural-
gas/jurisdiction-lng-plants.
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operations, maintenance, personnel, and fire protection.115 Its security regulations include
requirements for security procedures, protective enclosures, communications, lighting, and
monitoring.116 TSA also has jurisdiction over the security of LNG facilities, although it exercises
its authority through voluntary security guidelines, which cover risk assessment, criticality
assessment, and facility security measures.117 The Coast Guard has jurisdiction over the security
of LNG facilities on a waterfront that interact with vessels. It has promulgated a Facility Security
Rule which includes requirements for security procedures, access restrictions, cargo handling,
monitoring, security assessments, and security plans, among other provisions.118
Depending upon the nature and location of an LNG facility, PHMSA, the Coast Guard, and TSA
may share jurisdiction over its security. How these agencies work together to secure LNG
facilities used in rail transportation, and whether LNG shipments by rail or LNG facilities
associated with such shipments require additional security measures may be considerations for
Congress. Because TSA, PHMSA, and the Coast Guard also share jurisdiction over aspects of
freight rail security more broadly, and FRA is involved with enforcement, any regulatory changes
would likely need to account for the distinctive roles and regulations of the relevant agencies.
Legislative Actions in the 116th Congress
Although some Members of Congress have supported LNG shipment by rail, generally, and
Executive Order 13868, specifically, citing various perceived benefits, others have raised
concerns about the safety and security of such shipments.119 There have been several legislative
actions relevant to LNG shipment by rail in the 116th Congress.
A 2019 House appropriations bill amendment (H.Amdt. 468 to H.R. 3055) would have prohibited
appropriated funds from being used to carry out the LNG by rail provisions of Executive Order
13868 or to authorize LNG transportation in rail tank cars by issuance of a special permit or
approval. That amendment was not adopted.
The House Committee on Appropriations report (H.Rept. 116-106) accompanying Division H of
the Further Consolidated Appropriations Act, 2020 (P.L. 116-94) recommended funding of
$2,500,000 for FRA to research and mitigate risks associated with the rail transportation of
hazardous materials, specifically including LNG and tank car research. The report also directed
FRA, in collaboration with PHMSA, to support cooperative research on “methods to safely use
LNG as a fuel for locomotives and to transport LNG in bulk in tank cars” to “inform the
development of new regulations.”
The Protecting Communities from Liquefied Natural Gas Trains Act (H.R. 4306) would require
federal agencies to conduct further evaluation of the safety, security, and environmental risks of
transporting LNG by rail. On September 13, 2019, the bill was referred to the House Committee
on Transportation and Infrastructure, Subcommittee on Railroads, Pipelines, and Hazardous
Materials.
The Pipeline and LNG Facility Cybersecurity Preparedness Act (S. 300, H.R. 370) would require
the Secretary of Energy to enhance coordination among federal agencies, state agencies, and the

115 49 C.F.R §§193.2101 et seq.
116 49 C.F.R. §§193.2901-193.2917.
117 Transportation Security Administration, Pipeline Security Guidelines, March 2018.
118 33 C.F.R. §105.
119 See, for example, Floor Debate on H.Amdt. 232 During Consideration of the Bill, H.R. 3055, Congressional
Record, daily edition, vol. 165, part 106 (June 24, 2019), pp. H5053-H5055.
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energy sector “to ensure the security, resiliency, and survivability” of pipelines and “liquefied
natural gas facilities.” The bill does not define “liquefied natural gas facilities.” Depending upon
its interpretation, it could cover certain facilities (but not others) used in rail transportation of
LNG. The bill also would require DOE to coordinate response and recovery to physical and cyber
incidents “impacting the energy sector,” which would likely apply to attacks on LNG shipments
by rail. The recovery provision could involve the use of LNG shipments by rail as backup
supplies in the event of a pipeline disruption. On January 31, 2019, S. 300 was referred to the
Senate Committee on Commerce, Science, and Transportation. On November 20, 2019, H.R. 370
was reported by the House Committee on Energy and Commerce (H.Rept. 116-303, Part I) and
referred sequentially to the House Committee on Transportation and Infrastructure, Subcommittee
on Railroads, Pipelines, and Hazardous Materials.
The Moving Forward Act (H.R. 2) would authorize between $6 million and $8 million in FRA
funding to carry out further evaluation of LNG-by-rail safety. It would require FRA and PHMSA
to physically test DOT-113 rail tank cars to evaluate their performance in an accident or
derailment, analyze multiple LNG release scenarios, and examine tank car exposure to different
climate conditions across rail networks. Among other LNG safety provisions, the bill would
require the agencies to evaluate the public safety and environmental impact of an LNG release,
including the effect of route restrictions, speed restrictions, enhanced braking, and other
operational controls; train configuration; potential accident impact areas; air quality impacts;
advanced notice of shipment routes; first responder requirements; thermal radiation risks; and the
risks of LNG shipments in ISO containers. The bill would require the agencies to determine
whether new safety standards are needed for LNG transportation by rail. It would require a report
on the above within two years of enactment, independently verified by the GAO. The bill also
would rescind any special permit or approval for the LNG transportation by rail tank car issued
prior to enactment and would prohibit any regulation, special permit, or approval prior to the
conclusion of a specified study period. The bill passed in the House on July 1, 2020, and was
received in the Senate on July 20, 2020.

Author Information

Paul W. Parfomak
John Frittelli
Specialist in Energy and Infrastructure Policy
Specialist in Transportation Policy

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Rail Transportation of Liquefied Natural Gas: Safety and Regulation

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