applied to the collision load path without exceeding the crippling
strength of the vehicle. This paragraph would define crippling as the
maximum point on the load-versus-displacement characteristic. The load
magnitude required by this quasi-static compression load requirement
would be 50 percent higher than the 800,000-pound load required by
existing Sec.  238.203, which also requires that the carbody must
remain elastic to successfully meet the requirement. Because the
evaluation load would be increased by 50 percent, the corresponding
pass-fail criterion would require that the vehicle being evaluated have
an ultimate load carrying capacity (i.e., crippling resistance) equal
to or greater than 1.2 million pounds. To determine the adequacy of the
proposed ultimate load, in June 2011, FRA performed a series of quasi-
static compression tests on passenger railcars compliant with Sec.
238.203 and verified that these cars had an ultimate load capacity of
approximately 1.2 million pounds. This testing series established that
1.2 million pounds is a reasonable minimum standard for the crippling
strength of passenger equipment compliant with Sec.  238.203. The
results of that testing and corresponding FE modeling are summarized in
an FRA ``Research Results'' report,\13\ two technical papers,\14\ and
an FRA final report.\15\
---------------------------------------------------------------------------

    \13\ USDOT/FRA, ``Occupant Volume Integrity Evaluation in
Passenger Railcars.'' Research Results--Office of Railroad Policy
and Development, RR 12-01, February 2012.
    \14\ Carolan, M., Muhlanger, M., Perlman, B., and Tyrell, D.,
``Occupied Volume Integrity Testing: Elastic Test Results and
Analyses,'' American Society of Mechanical Engineers, Paper No.
RTDF2011-67010, September, 2011; Carolan, M., Perlman, B., and
Tyrell, D., ``Crippling Test of a Budd Pioneer Passenger Car,''
American Society of Mechanical Engineers, Paper No. JRC2012-74087,
April 2012.
    \15\ Carolan, M., Perlman, B., and Tyrell, D., ``Alternative
Occupied Volume Integrity (OVI) Tests and Analyses,'' U.S.
Department of Transportation, DOT/FRA/ORD-13/46, October 2013.

---------------------------------------------------------------------------

    Demonstration of compliance with any of the quasi-static
requirements may be achieved through testing to the specified load or a
combination of elastic testing and plastic analysis. Paragraph (b)(2)
would establish that, at a minimum, an end compression load of no less
than 337,000 pound-force (lbf) must be applied to the carbody structure
to validate the plastic analysis. In addition, these requirements would
establish the minimum level of model validation to be performed using
the results of a test of the same design. Nonetheless, FRA does not
intend for these proposed minimum requirements to replace sound
engineering judgment that higher force values may be appropriate to
obtain valid test results when designing and performing the compression
testing and FE modeling.
    Because paragraphs (b)(1)(ii) and (iii) would permit permanent
deformation to occur in the occupied volume of a vehicle during its
evaluation, it is likely a combination of elastic (i.e., non-
destructive) testing and elastic-plastic finite element analysis (FEA)
would be used to demonstrate a vehicle design's ability to meet either
of those two quasi-static compression load requirements. While
paragraph (b)(1)(i) would not permit permanent deformation to occur in
a design undergoing evaluation, FRA does not intend for the proposed
rule to prevent a combination of elastic testing to a load less than
800,000 lbs and FEA up to the target load of 800,000 lbs from being
used to demonstrate that a design's OVI complies with this first
requirement.
    As previously discussed, proposed paragraph (b)(2) states that, no
matter which of the three requirements that is chosen for evaluation of
a design's OVI is applied, a compression test also must be performed
and the applied longitudinal compression load must be at least 337,000
lbf (1500kN). This test is required to ensure the FE computer model
that is used to demonstrate alternative compliance can successfully
model the response of the carbody to the same loading condition as part
of a program of model validation. This value is equal to 1500 kN, which
is the compression load placed on the coupler support structures
required by European standard EN 12663 for Category P-II passenger
equipment. The ETF recommended this minimum value for the validation
test's elastic load and FRA adopted this minimum recognizing that
sufficient strains must be developed within the tested structure to
provide quality measurements necessary for validating a model.
    Finally, proposed paragraph (b)(3) states that compliance with
paragraph (b) of this section must be documented and submitted to FRA
for review and approval. In particular, we propose several options for
compliance with paragraph (b)(1), and FRA review and approval is
necessary to evaluate the approach taken to ensure compliance.
Section 238.705 Dynamic Collision Scenario
    In this section, FRA is proposing to introduce a dynamic collision
scenario analysis as the second part of the OVI evaluation of a Tier
III passenger trainset. PTC technology cannot protect against all
possible collision scenarios, such as collisions with trespassing
highway equipment at grade crossings or with other rolling stock
(freight or passenger equipment) during manual operations at 20 mph or
below. Accordingly, compliance with this requirement is necessary to
preserve the occupied volume, protecting all occupants on the trainset.
    As mentioned in the discussion of proposed Sec.  238.703 above,
each vehicle in the trainset would need to demonstrate it meets both
the OVI requirements in proposed paragraph (b) of that section and the
dynamic collision scenario requirements in proposed paragraph (b) of
this section. Further, as mentioned in the discussion of proposed Sec.
238.703, and as outlined in proposed appendix G, a Tier I passenger
trainset designed to alternative crashworthiness standards may comply
with this section instead of the requirements currently applicable to
Tier I passenger trainsets in Sec.  238.203.
    In combination with the quasi-static compression load requirements
discussed in proposed Sec.  238.703, the purpose of this proposed
dynamic collision scenario requirement is to ensure that survivable
space for the passengers and crew is preserved in up to moderately
severe accident conditions (i.e., conditions comparable to a head-on
collision at a speed of 20 to 25 mph, depending on the type of
equipment, into a stationary train). This requirement would also
provide a baseline level of protection for scenarios that may be more
severe, but less predictable with respect to loading conditions and
historical accident data. Although the dynamic collision scenario would
be conducted at the trainset level, the requirements described in this
section would be evaluated at the level of the trainset's individual
vehicles so no vehicle in the trainset may exceed the parameters
outlined in proposed paragraph (b) as a result of the dynamic collision
scenario.
    Proposed paragraph (a) outlines the required conditions under which
a dynamic collision scenario would be performed. Generally, the
collision scenario requires a dynamic impact to be simulated between
two trains: An initially-moving train and an initially-standing train.
The initially-moving train is the trainset undergoing evaluation,
either Tier III equipment or, as provided in appendix G, Tier I
equipment designed to alternative crashworthiness standards. The
initially-standing train is a locomotive-led consist of five
conventionally-designed passenger cars. The conventionally-designed
passenger cars have a prescribed weight and force-versus-displacement
characteristic.\16\ The pass/fail criteria for the scenario determine
whether there is sufficient preservation of occupied volume for
passengers and crew in the trainset undergoing evaluation.
---------------------------------------------------------------------------

    \16\ Appropriate weights and force-versus-displacement
characteristics for the conventionally-designed passenger cars can
be found in the Technical Criteria and Procedures Report.
---------------------------------------------------------------------------

    FRA expects the collision scenario would be executed for an impact
duration sufficient to capture the most severe portion of the collision
event. The actual amount of impact time required to simulate the
collision sufficiently would vary based upon the characteristics of the
trainset undergoing evaluation. Typically, the collision scenario would
be executed until all of the equipment, including the initially-
standing and initially-moving consists, is moving in the same direction
at approximately the same velocity. If all of the equipment is moving
together at approximately the same speed, no further car-to-car impacts
would occur, and the simulation would have been executed for a
sufficient duration to capture the most severe decelerations.
    There are various types of analyses that may be used to evaluate
the collision scenario requirements. These analyses include fully-
detailed FE models, lumped-parameter analyses, or a hybrid approach
where a combination of detailed FE modeling and lumped-parameter
techniques are used within the same simulation. An FEA of the scenario
is generally a highly-detailed simulation of the actual trainset
geometry. The parts making up the trainset are meshed into a large
number of elements, with each element having its own mass, stiffness,
and connection properties to the adjacent elements. A lumped parameter
analysis represents each car or section of a car within a trainset
using a small number of masses and a small number of non-linear
springs. At its extreme, each car consists

of a single mass and a single spring characteristic. A hybrid approach
may utilize an FE mesh to represent some structures (e.g., CEM
structures that undergo large deformations) and lumped-parameter
representations of other structures (e.g., cars far from the impacting
interface that experience little deformation). Any of the three types
of analyses is capable of developing the information needed to verify a
trainset's ability to meet the requirements of the collision scenario.
Additionally, because the centerlines of the initially-moving and
initially-standing trains are aligned with one another during this
scenario, a half-symmetric model may be used to represent the colliding
vehicles, as appropriate.
    Proposed paragraph (a)(1) requires the initially-moving train to be
made up of the equipment undergoing evaluation at its empty, ready-to-
run (AW0) weight.\17\ As highlighted above, this equipment can be
either Tier III equipment or, under appendix G, Tier I equipment
designed to alternative crashworthiness standards.
---------------------------------------------------------------------------

    \17\ ``AW0'' is a loading designation that is defined by the
manufacturer. Specifically, AW0 refers to the ``actual weight'' of
an empty vehicle. The phrase ``empty, ready-to-run weight'' is
typically how this designation is defined in a technical document.
---------------------------------------------------------------------------

    Proposed paragraph (a)(2) states that if the length of consists to
be used in service can vary, then the longest and shortest consist
lengths must both be evaluated under this section. This requirement is
intended to ensure the trainset's OVI is satisfactory when operated in
both the shortest and longest train consists that will be utilized in
service. The trainset undergoing evaluation must successfully meet the
collision scenario requirements for both its shortest and longest
configurations; it is not required to demonstrate other configurations
meet the requirements.
    Proposed paragraph (a)(3) states that if the trainset is intended
for use in push-pull service, then both the locomotive-led and cab-car-
led configurations shall be evaluated separately. This requirement is
intended to ensure sufficient OVI for all occupied spaces in the
trainset regardless of whether it is led by a cab car or a conventional
locomotive.
    Proposed paragraph (a)(4) describes the configuration of the
initially-standing train of conventional passenger equipment. As
provided in paragraph (a)(4)(i), this train is to be led by a rigid
locomotive weighing 260,000 pounds and also made up of five identical
coaches, each having a weight of 95,000 pounds. Paragraph (a)(4)(ii)
provides that the locomotive and each passenger coach crush in response
to applied force as specified in Table 1 to this section. Table 1
provides the non-linear, force-versus-crush relationship for the
passenger cars and locomotive comprising the initially-standing train.
These relationships are meant to be representative of typical crush
responses for passenger equipment; likewise, the weights given for the
conventional locomotive and conventional passenger cars are meant to be
representative of typical weights for passenger equipment. The weights
for the passenger cars and locomotives, the force-versus-crush
behavior, and the geometry for the standing locomotive are all provided
in the Technical Criteria and Procedures Report. Further detail on the
geometry of the locomotive can be found in that Report. In addition,
paragraph (a)(4)(iii) provides that the locomotive would be modeled
using the data inputs listed in appendix H to this part, so that the
locomotive's geometric design is as depicted in Figure 1 to appendix H.
    Proposed paragraphs (a)(5) through (10) are meant to ensure that
the collision scenario is evaluated under the same conditions by each
entity performing this type of evaluation. Proposed paragraph (a)(5)
explains that the scenario must be evaluated on tangent, level track.
    Proposed paragraph (a)(6) describes the initial velocities to be
assigned to the initially-moving consist. If the initially-moving
consist is led by a cab car or an MU locomotive, then it must have an
initial velocity of 20 mph. If the initially-moving consist is led by a
conventional locomotive, it must have an initial velocity of 25 mph.
These speeds were chosen based upon estimates of the upper limit of the
ability of conventionally-designed Tier I equipment to maintain its
occupied volume in a similar collision scenario.
    FRA intends for the requirements in proposed paragraphs (a)(7)
through (9) to simplify the modeling of the collision scenario and to
help ensure the scenario is evaluated consistently by different
entities. Paragraph (a)(7) provides that the coupler knuckles on the
impacting equipment shall be closed. Paragraph (a)(8) states that the
moving and standing consists are not braked. Paragraph (a)(9) states
that the initially-standing train is free to move only in the
longitudinal direction.
    Proposed paragraph (a)(10) would require that the model used to
demonstrate compliance with the dynamic collision requirements be
validated, and that model validation be documented and submitted to FRA
for review and approval. Regardless of the type of analysis employed to
demonstrate a trainset's ability to meet the collision scenario
requirements, the analytical model must undergo some level of
validation for the results to be considered acceptable. The validation
to be performed on the model used in the collision scenario would be in
addition to any validation required for a model used to demonstrate the
quasi-static OVI of the trainset undergoing evaluation. While full-
scale destructive testing of a trainset undergoing evaluation is not
expected, FRA expects that any designated energy-absorbing components
will be tested at the component-level. The results of these component
tests would be used to validate a model of the same type to be used to
demonstrate the trainset's ability to meet the dynamic collision
scenario. FRA also expects that any components that experience large
deflection or permanent deformation during the modeling of the
collision must be validated with some type of physical test.
    Proposed paragraph (b) would contain the crashworthiness and
occupant protection performance requirements the individual vehicles in
the initially-moving trainset involved in the dynamic collision
scenario must meet as described in paragraph (a)--i.e., the trainset
undergoing evaluation. Proposed paragraph (b)(1) outlines two
conditions for demonstrating that the initially-moving trainset
possesses sufficient crashworthiness to resist a significant loss of
occupied volume during the collision scenario. Only one of the two
performance conditions would have to be shown to be met to successfully
demonstrate compliance: No more than 10 inches of longitudinal,
permanent deformation of the occupied volume as a result of the impact,
as proposed in paragraph (b)(1)(i); or global vehicle shortening not
exceeding 1 percent over any 15-foot length of the occupied volume, as
proposed in paragraph (b)(1)(ii). These two performance conditions are
meant to permit different analysis techniques (e.g., lumped-parameter
or FEA) to be applied to evaluate the collision scenario.
    Proposed paragraph (b)(2) provides that if the option to use GM/
RT2100 is exercised to demonstrate compliance with any of the
requirements in Sec. Sec.  238.733, 238.735, 238.737, or 238.743, then
the average longitudinal deceleration of the center of gravity (CG) of
each vehicle during the dynamic collision scenario shall not exceed 5g
in any 100-millisecond (ms) time period. A plot of the 100-ms average
longitudinal deceleration versus time, in which the

curve never exceeds 5g, would suffice to demonstrate
compliance with paragraph (b)(2).
    Proposed paragraph (b)(3) sets out the criteria that must be met to
demonstrate the crashworthiness of the engineer's cab as a result of
the dynamic collision impact. Paragraph (b)(3)(i) states that a
survival space where there is no intrusion must be maintained around
each seat in the cab. Survival space is defined as extending a minimum
of 12 inches from each edge of the seat. Walls or other items
originally within this defined space, not including the operating
console, shall not further intrude more than 1.5 inches towards the
seat under evaluation.
    In addition, as a result of the impact, under paragraph (b)(3)(ii),
there shall be a clear exit path from the cab for the occupants, and,
under paragraph (b)(3)(iii), the vertical height of the compartment
shall not be reduced by more than 20 percent. FRA intends for proposed
paragraph (b)(3)(iii) to prevent loss of occupied volume that occurs
either through lifting of the floor or downward buckling of the
ceiling.
    Further, proposed paragraph (b)(3)(iv) provides that the operating
console shall not have moved closer to the engineer's seat by more than
2 inches as a result of the impact. Because portions of the operating
console in a given cab may originally be within the 12-inch survival
space defined in paragraph (b)(3)(i) before the impact, it is important
that the console not move more than 2 inches closer to the engineer's
seat and impede the engineer from exiting the cab following the impact.
The allowable encroachment for the operating console is one-third
larger than the 1.5 inches allowed for walls or other items originally
within the 12-inch survival space. This larger allowance assumes the
initial configuration is designed so there is sufficient space for the
engineer to readily get into and out of his or her seat, as well as
space to comfortably situate himself or herself for normal operation of
the train. Consequently, console movement of 2 inches or less can be
allowed without inhibiting or preventing egress. If the engineer's seat
is part of a set of adjacent seats, the requirements of this paragraph
(b)(iv) would apply to both seats. This seating arrangement is in the
cabs of Amtrak's Acela Express trainsets.
Section 238.707 Override Protection
    This proposed section would contain the requirements for analyzing
the ability of a Tier III passenger trainset to resist vertical
climbing or override at its collision interface locations during a
dynamic collision scenario. This proposed section would examine the
vertical displacement behavior of colliding equipment under an ideal
impact scenario where an initially-moving Tier III trainset and an
initially-standing conventional train are aligned. This section would
also prescribe an impact scenario where the interface of the colliding
equipment is translated both laterally and vertically by 3 inches to
ensure that override is resisted during an impact when the two trains
are not perfectly aligned. Evaluating the colliding equipment's ability
to resist override in an offset impact condition helps to demonstrate
that the override features are robust.
    FRA clarifies that Tier III passenger trainsets would have to
comply with both paragraphs (a) and (b) of this section. FRA also
clarifies that under proposed appendix G, a Tier I passenger trainset
designed to alternative crashworthiness standards may demonstrate an
appropriate level of override protection by complying with the
requirements this section proposes instead of complying with the
requirements applicable to Tier I passenger trainsets in Sec.  238.205,
Anti-climbing mechanism, and Sec.  238.207, Link between coupling
mechanism and car body. In general, the requirements proposed in this
section were developed as an alternative to demonstrating anti-climbing
capabilities in current Sec.  238.205 and the capability of the link
between the coupling mechanism and carbody to resist the loads in
current Sec.  238.207. While compliance with both Sec. Sec.  238.205
and 238.207 requires meeting a set of quasi-static, vertical load
cases, the requirements proposed in this section were developed as a
dynamic performance standard.
    Proposed paragraph (a)(1) contains two sets of initial conditions
for analyzing the ability of the evaluated trainset to resist vertical
climbing or override during a dynamic collision scenario, and states
these conditions must be applied using the dynamic collision scenario
in proposed Sec.  238.705(a). Criteria for evaluating the dynamic
collision scenario for each set of initial conditions are provided in
proposed paragraph (a)(2). Because the same model may be used both to
demonstrate compliance with the requirements of Sec.  238.705 and the
requirements of paragraphs (a) and (b) of this section, the model must
be validated with test data in such a way as to provide confidence in
the validity of the results of the collision analyses. In this regard,
if the components that experience large deflection or permanent
deformation in the analysis described in Sec.  238.705 also experience
large deflection or permanent deformation in the analysis described in
paragraph (a)(2) of this section, then the same test results may be
used to validate the model. If the performance of the components that
undergo large deformation in the analysis described in paragraph (a)(2)
of this section is not validated with test data as part of the
validation of the model used in Sec.  238.705, then additional
validation testing must be performed to validate the model being used
to demonstrate performance under paragraph (a)(2).
    Proposed paragraph (a)(1)(i) describes the first condition to be
used in the collision simulation to demonstrate anti-climbing
performance. This paragraph provides that all vehicles in both the
initially-moving and the initially-standing train consists must be
positioned at their nominal running heights with the centerlines of the
initially-moving and initially-standing trains aligned. Because the
centerlines of the colliding vehicles would be aligned with one
another, a longitudinally half-symmetric model may be used to simulate
this collision scenario, as appropriate. FRA intends for this initial
condition to represent an ideal collision situation where the colliding
vehicles are initially aligned with one another.
    Proposed paragraph (a)(1)(ii) describes the second condition to be
used in the collision simulation as a 3-inch lateral and 3-inch
vertical offset of the interface of the colliding equipment. The
lateral and vertical offsets must be applied simultaneously in the same
simulation. Evaluating the equipment offset in this manner will
demonstrate that the anti-climb features are of a robust design,
capable of preventing climbing when the colliding vehicles are not
perfectly aligned. Because this simulation requires a lateral offset
between the initially-standing and initially-moving consists, a
symmetric boundary condition may not be employed (i.e., the full width
of each consist must be modeled).
    Proposed paragraph (a)(2) explains the pass/fail criteria that must
be successfully met to demonstrate a trainset possesses adequate anti-
climb features for its colliding interface. The criteria must be met
for each set of initial conditions in paragraphs (a)(1)(i) and (ii) for
demonstrating appropriate resistance to override between colliding
equipment. Paragraph (a)(2)(i) would provide that the relative
difference in elevation of the underframes between the colliding
equipment in the initially-moving and initially-standing train consists
may not change by more than 4 inches at any point during the

simulation. Because the initially-standing consist is permitted only
longitudinal motion under Sec.  238.705(a)(9), no vehicle in the
initially-standing consist will experience any vertical motion. Thus,
the change in elevation of the initially-moving trainset's underframe
would be measured relative to the underframe of the initially-standing
consist. To evaluate this scenario properly, the collision simulation
must be run until all vehicles in the initially-moving and the
initially-standing consists are moving in the same direction at
approximately the same velocity.
    Proposed paragraph (a)(2)(ii) contains the second pass/fail
criterion to be met to demonstrate resistance to override between
colliding equipment. No tread of any wheel of the first vehicle of the
initially-moving consist may rise above the top of the rail by more
than 4 inches. This condition must be evaluated throughout the duration
of the collision simulation, not only at the end of the collision. To
evaluate this scenario properly, the collision simulation must be
executed until all vehicles in the initially-moving and the initially-
standing train consists are moving in the same direction at
approximately the same velocity.
    Proposed paragraph (b) contains the evaluation methodology for
demonstrating the appropriate level of override protection for
connected equipment in a Tier III trainset. This paragraph would
examine the vertical displacement behavior of coupled equipment under
an ideal impact scenario where the vehicles within the initially-moving
train are aligned. It also would prescribe an impact scenario where the
first coupled interface of the initially-moving train is translated
both laterally and vertically by 2 inches. Evaluating the connected
equipment's ability to resist override in an offset impact condition is
necessary to demonstrate the override features are robust and can
resist override during an impact where the coupled vehicles are not
perfectly aligned.
    Proposed paragraph (b)(1) explains the conditions for analyzing the
ability of connected equipment to resist vertical climbing or override
at the coupled interfaces during a dynamic collision scenario, using
the scenario described in Sec.  238.705(a). Like paragraph (a) of this
section, each set of conditions in paragraphs (b)(1)(i) and (ii) must
be evaluated independently. Criteria for evaluating the dynamic
collision scenario for each set of conditions are in paragraph (b)(2).
As noted in the discussion of paragraph (a), because the same model may
be used to demonstrate compliance with the requirements of Sec.
238.705 and the requirements of this section, the model must be
validated with test data in a way that provides confidence in the
validity of the results of the collision analyses. The discussion of
model validation in paragraph (a) applies equally to model validation
for purposes of paragraph (b).
    Proposed paragraph (b)(1)(i) describes the first condition to be
used for collision simulation to demonstrate override protection for
connected equipment. This paragraph provides that all vehicles in both
the initially-moving and the initially-standing train consists must be
positioned at their nominal running heights, with the centerlines of
the initially-moving and initially-standing trains aligned. Because the
centerlines of the colliding vehicles would be aligned with one
another, a longitudinally half-symmetric model may be used to simulate
this collision scenario, as appropriate. This initial condition is
meant to represent an ideal collision situation where the colliding
vehicles are initially aligned with one another.
    Proposed paragraph (b)(1)(ii) would explain that the second
condition to be used in the collision simulation is a 2-inch lateral
and 2-inch vertical offset of the first connected interface between
vehicles in the initially-moving train. The lateral and vertical
offsets must be applied simultaneously in the same simulation.
Evaluating the equipment offset in this manner would demonstrate that
the anti-climb features are of a robust design that would prevent
climbing when the vehicles in the initially-moving trainset are not
perfectly aligned. Because this simulation requires a lateral offset
between the vehicles of the initially-moving consist, a symmetric
boundary condition may not be used (i.e., the full width of each
consist must be modeled).
    Proposed paragraph (b)(2) sets out the pass/fail criteria that must
be successfully met to demonstrate a Tier III trainset possesses
adequate anti-climb features to protect the vehicles connected in the
trainset from overriding each other. The criteria must be met for each
set of initial conditions provided in paragraphs (b)(1)(i) and (ii) to
demonstrate appropriate resistance to override between connected
equipment. Proposed paragraph (b)(2)(i) would provide that the relative
difference in elevation of the underframes between the connected
equipment in the initially-moving train may not change by more than 4
inches at any point during the simulation. To evaluate this scenario
properly, the simulation must be run until all vehicles in the
initially-moving and the initially-standing consists are moving in the
same direction at approximately the same velocity.
    The 4-inch vertical difference in paragraph (b)(2)(i) is a pass/
fail criterion and must be measured relative to the initial heights of
the connected equipment. A change in underframe height in excess of 4
inches would indicate one of the two connected vehicles has begun to
climb and override the other.
    Proposed paragraph (b)(2)(ii) contains the second pass/fail
criterion to be met to demonstrate resistance to override between
connected equipment. No tread of any wheel of the initially-moving
train may rise above the top of the rail by more than 4 inches. This
condition may not be exceeded at any point during the simulation. To
evaluate this scenario properly, the simulation must be executed until
all vehicles in the initially-moving and the initially-standing
consists are moving in the same direction at approximately the same
velocity.
Section 238.709 Fluid Entry Inhibition
    This section proposes requirements for fluid entry inhibition for
the skin covering the forward-facing end of a Tier III trainset. The
proposed requirements are largely the same as those in Sec.  238.209(a)
for Tier I locomotives, including MU locomotives and cab cars. Section
238.209(a) requires that the front end of a Tier I locomotive be
covered by a skin equivalent to a half-inch-thick, 25-kilopound-per-
square-inch (ksi) steel plate to prevent the entry of fluids into the
locomotive cab in the event of a collision. While that specific
requirement is easily applied to conventional designs, many of which
may still make use of steel sheets for the outer skin, it is more
difficult to apply to the complex, aerodynamic shapes of modern
passenger trainset front ends, which often are comprised of various
structures, including crash energy management elements. Because the
consideration of aerodynamics and crash energy management is
significant, this section proposes to account for the use of more
modern designs and materials to construct a passenger trainset front
end so it can be evaluated effectively.
    FRA notes that, while this section focuses on the prevention of
fluid entry, it also establishes a minimum level of penetration
resistance that may be applied more generally. Because this section is
based on Sec.  238.209(a), which identifies two important carbody

characteristics for the protection of cab occupants in conventional
equipment designs, material thickness and strength, this section offers
protection for more hazards than the entry of fluid alone.
    Specifically, proposed paragraph (a)(1) provides that the skin
covering the front-end structure of a Tier III trainset must maintain a
resistance to penetration into the cab equivalent to that of the half-
inch-thick sheet of 25-ksi steel plate, as required by Sec.
238.209(a)(1)(i) for Tier I locomotives. This may be achieved using an
outer skin of an equivalent strength; a combination of materials
between the engineer and the outside environment; or a composite
material of a lesser thickness, if an equivalent level of penetration
resistance is maintained. To demonstrate compliance, the sum of the
thicknesses and material strength of all elements (e.g., skin and
structural elements) may be considered, when measured from the
structural leading edge of the trainset up to, and including, the
interior structural wall of the cab at its weakest location, when
projected onto a vertical plane, just forward of the engineer's normal
operating position.
    By permitting additional methods to achieve equivalent penetration
resistance, FRA recognizes that even though most modern designs may
make use of lighter weight materials for aerodynamic skins (e.g.,
aluminum, fiberglass), it does not imply that the protection provided
is any less substantial. In fact, the combination of skin, structure,
and crash energy management features in front of the engineer may
actually provide more protection than the half-inch-thick, 25-ksi steel
plate. It is important to note, however, that FRA intends for the
performance requirement in this paragraph to be evaluated laterally
across the entire width of the cab, including all carbody structures
just forward of the engineer's normal operating position. This would
demonstrate protection equivalent to that provided by the referenced
steel plate exists across the entire width of the cab when projected in
front of the engineer. Non-structural elements or features, such as the
operating console and insulation materials, would not be taken into
account in demonstrating compliance.
    Proposed paragraph (a)(2) is derived from the existing requirement
for fluid entry inhibition for Tier I locomotives in Sec.
238.209(a)(1)(ii). It would also be applied so it is consistent with
the design of modern passenger trainset front end structures. This
recognizes that various techniques may be employed to provide fluid
entry inhibition characteristics, particularly through the use of
flexible and impermeable materials.
    Proposed paragraph (a)(3) would complement the requirements of
paragraph (a)(1) by prescribing that the required front-end protective
skin (or its equivalent) be affixed to the main structural members
(e.g., collision and corner posts) to ensure the integrity of the
overall front-end structure. In this regard, FRA makes clear that the
requirement for front-end protective skin (or its equivalent) is
independent of the requirements proposed for the other structural
features at the front end of the trainset--and indeed provides an
additional layer of protection. Proposed paragraph (a)(3) is also
derived from the existing requirement for Tier I locomotives in Sec.
238.209(a)(1)(iii).
    Since this section expressly provides flexibility to demonstrate
compliance, it inherently allows various means of compliance that could
be considered acceptable. Consequently, proposed paragraph (b) would
require that, at a minimum, detailed structural drawings be submitted
for FRA review, with pertinent calculations to demonstrate compliance
with the requirements of paragraph (a) of this section. FRA believes it
is necessary to provide such detail on how the requirements of
paragraph (a) are to be met given the expected use of front-end
protection in Tier III trainsets equivalent to the steel plate
specified in paragraph (a), and in Tier I trainsets designed to
alternative crashworthiness standards, as provided in proposed appendix
G.
    FRA is not aware of any international standard regarding fluid
entry inhibition. These proposed requirements are necessary to protect
the occupied volume because of the front end structure of Tier I and
Tier III equipment as this location is vulnerable in a highway grade
crossing collision if a fuel tank that is part of or being transported
by the highway vehicle ruptures. See 64 FR 25540. However, equipment
designed to international standards may be able to meet this
requirement as designed, without modification, due to the large
structure that is usually present on the leading ends of the equipment.
FRA invites comment on this proposed section and specifically on
whether application of the proposed requirements is clear.
Section 238.711 End Structure Integrity of Cab End
    In this section, FRA proposes requirements to ensure the structure
of cab ends for Tier III trainsets (and Tier I trainsets designed to
alternative crashworthiness standards, under proposed appendix G)
provides a minimum level of protection for the engineer and other cab
occupants, equivalent to the collision post and corner post
requirements for Tier I equipment in subpart C of this part. Accident
history shows the occupied volume can be penetrated by large, blunt
objects that contact the end structure, particularly in grade crossing
collisions, threatening the safety of the crew and other occupants. For
such collision scenarios, the end structure can be designed to act as
an integrated structure, absorbing energy as it deforms to provide
increased occupied volume protection.
    Specifically, FRA is proposing to cross-reference the requirements
of appendix F to this part, Alternative Dynamic Performance
Requirements for Front End Structures of Cab Cars and MU Locomotives.
FRA added appendix F to this part in the final rule on Passenger
Equipment Safety Standards; Front End Strength of Cab Cars and
Multiple-Unit Locomotives. See 75 FR 1180, Jan. 8, 2010. In particular,
these dynamic performance requirements facilitate testing of end frame
designs without readily identifiable collision or corner post
structures. They provide an option to demonstrate the dynamic
performance of front end structures when impacting a rigid object,
instead of the static load testing requirements prescribed in
Sec. Sec.  238.211 and 238.213 for collision posts and corner posts,
respectively. These dynamic performance requirements do not prescribe
the strength of the main structural members (i.e., collision posts and
corner posts), but rather prescribe energy absorption requirements for
the end structure in grade crossing collision scenarios. Instead of
focusing on whether an individual collision post or corner post
structure is capable of resisting the applied loads, the focus is more
appropriately placed on the ability of the end frame structure as an
integrated whole to withstand collisions. The collision scenarios can
be evaluated through the use of FEA, or testing, or both. The
requirements are performance-based and each must be evaluated using a
prescribed collision scenario of a rigid object impacting the end
structure.
Section 238.713 End Structure Integrity of Non-Cab End
    In this section, FRA proposes requirements to ensure the structure
of the non-cab ends of Tier III trainsets (and Tier I trainsets
designed to alternative crashworthiness standards under proposed
appendix G to this part) provides a minimum level of protection

for occupants equivalent to that required for Tier I equipment in
subpart C of this part. These proposed requirements help ensure the
integrity of the components that make up any non-cab end of a passenger
trainset unit. The proposed requirements are substantially similar to
the Tier I collision and corner post requirements in Sec. Sec.  238.211
and 238.213, respectively. The proposal would also specifically permit
trainsets with particular safety features, such as pushback couplers,
the flexibility to demonstrate required safety performance instead of
separate collision post structures.
    Proposed paragraph (a) explains that the requirements of paragraphs
(b) and (c) of this section apply to a Tier III trainset other than at
cab ends.
    Proposed paragraph (b) contains the requirements for collision post
structures at any non-cab end of a trainset unit. The proposed
requirements are the same as the requirements for collision post
structures in Sec.  238.211(a)(1), which generally apply to the ends of
Tier I passenger equipment other than at the cab end of a locomotive.
While the heading of this proposed paragraph is ``Collision post
requirements,'' FRA intends for these proposed requirements to apply to
the structures otherwise located at approximately the one-third points
laterally at any non-cab end of the trainset unit, whether or not the
structures are identified as collision posts.
    Proposed paragraph (b)(1) explains that at least one set of
specified requirements must be met. Paragraph (b)(1)(i) is the first
set of requirements addressing collision post structural protection.
This paragraph provides that there would be two full-height collision
posts, located at approximately the one-third points laterally across
the width of the end of the trainset unit. Each collision post would be
required to have an ultimate longitudinal shear strength of at least
300,000 pounds, with the load applied at the top of the underframe
member to which it is attached. This paragraph further states that if
reinforcement is used to provide the required shear strength, the
reinforcement shall have full value, meaning a width equal to the width
of the collision post, for a distance of 18 inches up from the
underframe connection and then taper to a location approximately 30
inches above the underframe connection.
    Proposed paragraph (b)(1)(ii) provides an alternative to meeting
the requirements of paragraph (b)(1)(i). This paragraph states that an
equivalent end structure may be used instead of the specific collision
post structures described in paragraph (b)(1)(i). The equivalent end
structure would be required to withstand the sum of the forces that
would otherwise be applied to each individual post.
    Proposed paragraph (b)(2) provides conditions under which collision
posts are not required in the non-cab end structure of a Tier III
trainset unit. This paragraph explains an exception to the requirements
of paragraph (b)(1) for the non-cab end of any unit with push-back
couplers and interlocking anti-climbing mechanisms, and for the non-cab
ends of a semi-permanently coupled consist. To apply this exception, a
non-cab end of a trainset unit must demonstrate that its inter-car
connection can prevent disengagement and telescoping to the same extent
as equipment satisfying the anti-climbing and collision post
requirements of subpart C of this part. The exception in proposed
paragraph (b)(2) to the specific collision post requirements for
trainset units with certain design features is similar to an exception
to the collision post requirements in the existing Tier I requirements
in Sec.  238.211(d). Proposed paragraph (b)(2) further specifies that
the criteria in proposed Sec.  238.707(b) must be applied to evaluate
whether a Tier III trainset unit's inter-car connection can prevent
such disengagement and telescoping. Section 238.707 contains the
proposed requirements for demonstrating override resistance for
connected equipment during a dynamic collision simulation. FRA intends
for application of Sec.  238.707(b) to provide clarity and guidance on
the type of analysis FRA expects would be used to demonstrate a
particular trainset unit fulfills the conditions of the exception when
there are no collision posts at the non-cab end.
    Proposed paragraph (c) contains the requirements for corner post
structures on the non-cab end of a Tier III passenger car. Notably,
unlike requirements for collision posts at non-cab ends, requirements
for corner posts would not apply to non-cab ends of all units in a Tier
III passenger trainset--only Tier III passenger trainset units that are
passenger cars. Collision post requirements are necessary for each end
of any trainset unit, even if only occupied by crewmembers at one end,
to help prevent the uncontrolled crushing or climbing of trainset units
that could tend to misalign the trainset or cause telescoping that
could endanger the crew and passengers. Corner posts do not protect
against the misalignment of trainset units in the same way, and would
not be required by this rule if the end of the trainset unit is not
designed to be occupied by crewmembers or passengers. Specifically, for
a passenger car that has a cab equipped with one or more control stands
or consoles designed for an engineer to operate the trainset, the
requirements of Sec.  238.711 would apply to the cab end. Otherwise,
the requirements of this paragraph would apply to the non-cab end of a
passenger car, including any end of a passenger car without a cab.
    Although the proposed heading of this paragraph is ``Corner post
requirements,'' FRA makes clear these proposed requirements apply to
the corner structures at the non-cab ends of passenger cars, whether or
not the structures are identified as corner posts. The majority of the
corner structure requirements provided in this section are analogous to
the Tier I corner post requirements in Sec.  238.213.
    The proposed requirements in paragraph (c)(1) apply to each non-cab
end of a passenger car and would require that there be two side
structures, placed forward of the occupied volume, capable of resisting
the forces specified in paragraphs (c)(1)(i) through (iii). These
structures do not necessarily need to be located on the absolute
corners of the carbody if they are located in a manner that protects
the occupied volume. FRA is not aware of any international standards or
requirements for corner posts that are equivalent to the proposed
requirements. The proposed requirements are intended to address
accident conditions like those of the commuter train derailment and
collision in Bridgeport, CT, on May 17, 2013. In that accident, a
commuter train derailed toward an adjacent track such that the non-cab
end of a passenger car protruded into the right-of-way of an oncoming
train. There was structural damage to the protruding corner, but the
corner post resisted loss of the occupied volume to avoid fatal
injuries.
    Proposed paragraph (c)(1)(i) provides the first load case and pass/
fail requirement to be applied to the corner structures at non-cab
ends. This paragraph states that each corner structure must resist a
150,000-pound horizontal force at the height of the floor without
failure. Proposed paragraph (c)(1)(ii) provides the second load case
and pass/fail requirement. This paragraph states that each corner
structure must resist a 20,000-pound horizontal force at the height of
the roof without failure. Proposed paragraph (c)(1)(iii) provides the
third load case and pass/fail requirement. This paragraph states that
each corner structure must resist a 30,000-pound

horizontal force applied at a point 18 inches above the top of the
floor without permanent deformation.
    Proposed paragraph (c)(2) states that the orientation of the
applied horizontal forces shall range from longitudinal inward to
transverse inward, consistent with the Tier I requirements in Sec.
238.213.
    Proposed paragraphs (c)(3) and (4) do not have explicit
counterparts in the Tier I requirements in Sec.  238.213. FRA intends
for each paragraph to address the way to apply the evaluation loads to
the structure at non-cab ends. Paragraph (c)(3) states that for each
evaluation load, the load shall be applied to an area of the structure
sufficient enough to prevent local crippling or punching through the
material at the point of load application. Paragraph (c)(4) states that
the load area shall be chosen to be appropriate for the particular car
design and shall not exceed 10 inches by 10 inches. These two
paragraphs, addressing the areas of the corner structure over which the
load must be applied, are intended to guide the planning of the tests
and analyses undertaken to demonstrate compliance with the corner
structure requirements. FRA recognizes that a highly localized load
application can result in localized deformation and, as a consequence,
result in an evaluation test or analysis that is not descriptive of the
entire corner structure's behavior. At the same time, too large a load
application area would not result in a proper evaluation of the corner
structure at the discrete locations integral to demonstrating the
strength of the structure. While FRA provides this guidance, the
entities (e.g., manufacturers, testing facilities, consultants)
performing the evaluation would use their engineering judgment to
determine the selection of the loading mechanism (i.e., physical load
application device in the case of a test, or boundary conditions in the
case of a computer simulation) and load application area for evaluation
purposes consistent with the proposed requirements.
    In addition, FRA notes that because two of the three load cases
described in paragraph (c)(1) permit permanent deformation to occur
during the evaluation (provided the ultimate strength of the post is
not reached), FRA envisions that FEA or another appropriate simulation
tool would be used to perform the evaluation. FRA also expects any
analysis model used to demonstrate compliance with this paragraph and
the other structural requirements in this part, would be properly
validated using test data to demonstrate the model's ability to
properly reflect the relevant behaviors.
Section 238.715 Roof and Side Structure Integrity
    FRA is proposing that the roof and side structure integrity
requirements for Tier III trainsets (and Tier I trainsets designed to
alternative crashworthiness standards under proposed appendix G to this
part) equal those requirements in Sec.  238.215, ``Rollover strength,''
and Sec.  238.217, ``Side structure.''
    Section 238.215 currently requires a carbody to be designed so that
the weight of the car can be supported by either the roof of the car,
or by specified sidewall structural members, without resulting in
stresses exceeding one-half of the stress necessary to cause either
yielding or buckling. FRA expects that compliance with this requirement
would be demonstrated through FEA modeling of the structural carbody.
Moreover, FRA expects that the FEA model would have been subjected to a
program of model validation to demonstrate the model's ability to
accurately represent the structure. Further discussion of Sec.  238.215
is in the original Passenger Equipment Safety Standards final rule. See
64 FR 25607, 25608.
    Section 238.217 currently includes design requirements for the
sidewall stiffness of Tier I passenger equipment. This section codifies
longstanding design practice in the U.S. Compliance with this section
may be demonstrated through hand calculations. FRA does not expect
compliance to require physical testing or computer simulation, although
these methods of evaluation may be used. Further discussion of Sec.
238.217 is in the original Passenger Equipment Safety Standards final
rule. 64 FR 25608, 25609.
Section 238.717 Truck-to-Carbody Attachment
    In this section, FRA proposes requirements to demonstrate the
integrity of truck-to-carbody attachments on a Tier III trainset (or a
Tier I trainset designed to alternative crashworthiness standards under
proposed appendix G to this part) during a dynamic impact. The
requirements in either paragraph (a) or (b) may be applied; a given
design must demonstrate it complies with only one set of requirements.
FRA provided the two sets of requirements to permit different types of
analyses to be used to demonstrate the trainset units possess adequate
truck attachment strength. If a trainset features more than one type of
truck or more than one type of truck-to-carbody attachment,
satisfactory truck-to-carbody attachment strength must be demonstrated
for each design.
    Paragraph (a) proposes demonstrating truck-to-carbody attachment
integrity by showing compliance with the requirements in Sec.  238.219.
Discussion of Sec.  238.219 is in the original Passenger Equipment
Safety Standards final rule, 64 FR 25609, 25610, May 12, 1999, and in
amendments to the final rule, 67 FR 19977, 19978, Apr. 23, 2002.
    Proposed paragraph (b) contains the second option for demonstrating
truck-to-carbody attachment integrity. In this paragraph, the truck-to-
carbody attachment evaluation loads would be applied at the CG of the
truck and each load case would be evaluated separately. Additionally,
the loads would be applied quasi-statically for each load case. For
each of the quasi-static load cases, the applied load may not cause any
permanent deformation in the truck attachments or carbody.
    Proposed paragraph (b)(1) describes the first of three quasi-static
loads that must be evaluated. The load is stated as a 3g vertical load
acting downward on the mass of the truck (i.e., pulling the truck
toward the ground). Because a 3g vertical load acting upward on the
mass of the truck would force the truck into contact with the underside
of the carbody, only the 3g downward vertical load case must be
evaluated to demonstrate sufficient attachment strength between the
truck and carbody.
    Proposed paragraph (b)(2) describes the second of the three quasi-
static loads to be evaluated. The load is stated as a 1g lateral load
acting on the mass of the truck. Because the lateral load must be
evaluated at the CG of the truck, this load would generate a moment (or
torque) in the truck-to-carbody attachments. Additionally, the vertical
reaction that develops as a result of the lateral load must also be
considered and evaluated simultaneously with the lateral load itself.
FRA expects that if the truck-to-carbody attachments are not symmetric
from side to side, the lateral load case would be evaluated for a
lateral load acting independently in both the positive lateral and
negative lateral (e.g., inward and outward) directions.
    Proposed paragraph (b)(3) describes the final three quasi-static
loads to be evaluated. The load is stated as a 5g longitudinal load
acting on the mass of the truck. Because the longitudinal load must be
evaluated at the CG of the truck, this load would also generate a
moment (or torque) in the truck-to-carbody attachments. The vertical
reaction that develops as a result of the longitudinal load must also
be considered and

evaluated simultaneously with the longitudinal load.
    Demonstrating the truck can remain attached under a 5g quasi-static
longitudinal load is contingent on complying with the proposed
requirements in paragraphs (b)(3)(i) and (ii), derived from the dynamic
collision scenario results described in Sec.  238.705(a) in which a
moving train impacts a standing train under specified conditions.
During the collision scenario Sec.  238.705(a) describes, the average
longitudinal deceleration at the CG of the vehicle containing the truck
under evaluation (and its attachments) may not exceed 5g (paragraph
(b)(3)(i)), and the peak longitudinal deceleration of the truck may not
exceed 10g (paragraph (b)(3)(ii)). The longitudinal deceleration of the
truck must be measured during the collision scenario at the CG of the
truck.
    Because the initially-moving and initially-standing train consists
are aligned with one another in the collision scenario described in
proposed Sec.  238.705(a), a half-symmetric model may be used, as
appropriate, to demonstrate compliance with proposed paragraph (b)(3)
of this section. To use a half-symmetric model properly to demonstrate
truck attachment integrity, the truck and its attachments must also be
symmetric from side to side (e.g., using the same attachment
mechanism(s) in the same position(s) relative to a vertical-
longitudinal plane at the center of the vehicle).
    Proposed paragraph (c) provides an alternative to demonstrating
compliance with paragraph (b)(3). Paragraph (c) would require
demonstrating the truck remains attached after a dynamic impact under
the nominal conditions in the dynamic collision scenario described in
Sec.  238.705(a). Because the requirements of paragraph (b)(3) may only
be applied to a truck and carbody meeting the deceleration requirements
in paragraphs (b)(3)(i) and (ii), respectively, paragraph (c) may be
used to demonstrate truck-to-carbody attachment when the requirements
in paragraph (b)(3) are exceeded.
    Proposed paragraph (d) states that for the purposes of this
section, the mass of the truck includes the axles, wheels, bearings,
truck-mounted brake system, suspension system components, and any other
component attached to the truck by design. This description of what the
mass of the truck includes is the same as that in Sec.  238.219. FRA
expects the mass of the truck, including the components attached, would
be documented.
    Finally, proposed paragraph (e) emphasizes that truck-to-carbody
attachment integrity must be demonstrated using a validated model. If
the model employed has not been validated by means like those required
to comply with Sec.  238.705, then additional testing must be performed
to validate the model being used to demonstrate performance with this
requirement.
Glazing
Section 238.721 Glazing
    This section would define the requirements for exterior glazing
(i.e., side- and end-facing exterior windows and windshields) to be
installed on Tier III trainsets. The requirements of this section
outline performance standards for both the cab and non-cab areas of the
trainsets. The performance metrics for the non-cab areas adopt the
requirements of part 223 of this chapter to maintain compatibility with
existing Tier I trainsets. FRA developed the requirements for the cab
areas from the recommendations the Tier III Cab Glazing Task Group
provided.
    The approach FRA used to develop glazing requirements for cab
areas, much like its approach to Tier III in general, represents a
balance between maintaining compatibility with existing Tier I
equipment and the adoption of service-proven techniques to protect
against potential risks encountered with high-speed operation. In this
respect, it is important to note that, while glazing exposed to the
direction of train motion would be more vulnerable due to the speed of
the trainset, the right-of-way must also be secured and protected
appropriately against potential hazards to the glazing in areas where
Tier III trainsets will operate above Tier I speeds. Such hazards
include the launching of objects at the train. For example, substantial
fencing in conjunction with intrusion detection systems are common
protections provided for high-speed systems where an overpass spans the
right-of-way (ROW). These additional infrastructure improvements
represent a significant increase in ROW protection, which are not
typically present on most U.S. rail corridors, but would be expected
for Tier III high-speed corridors. Indeed, under FRA's Track Safety
Standards, a ``right-of-way plan'' for Class 8 and 9 track, which
corresponds to the speed range for Tier III high-speed corridors, must
be submitted to FRA for approval and address the prevention of
vandalism, launching of objects from overhead bridges or structures
into the path of trains, and intrusion of vehicles from adjacent ROWs.
See 49 CFR 213.361.
    Risks posed to exterior glazing may differ greatly depending on the
location and orientation of the installed glazing. For this reason, cab
glazing is further segregated into two distinct categories: One for
end-facing locations (e.g., windshields), and one for cab side windows
and glazing (if equipped). Since the two locations may present
different risks, the definition of ``end-facing'' is important to
establish how cab glazing compliance is evaluated. This subject was
discussed on a number of occasions during the task group meetings as
both the part 223 definitions and international standards were
considered. However, the task group concluded the language in part 223
was generally sufficient, although FRA proposes revisions to this
section and the definitions for ``glazing, end-facing'' and ``glazing,
side-facing'' in Sec.  238.5. FRA agrees with the task group and
intends for the proposed revisions to the glazing definitions to
clarify that the end-facing glazing requirements do not apply to
certain locations in a semi-permanently connected train consist that,
while on the end of a vehicle, are exposed to lesser risk.
    Proposed paragraph (b) describes the requirements for end-facing
cab glazing and represents the most substantial change from the
traditional FRA Type I performance requirements in part 223. End-facing
cab glazing on Tier III trainsets would be designated as Type IHS.
Since the challenge to glazing in this location is directly related to
the speed of the trainset, considerable discussion was devoted to this
topic within the task group. Although different approaches were
discussed, the efforts of the group eventually focused on finding a
reliable and repeatable large object impact test procedure, and
appropriate performance metrics, to replace the traditional ``cinder
block test.''
    Since the windshield of any vehicle must meet several performance
criteria to provide adequate protection, durability, and visual
clarity, quality assurance and control are imperative. In this respect,
the task group widely accepted that the current Type I large object
impact test presents too many variables and challenges to reliably and
accurately assess the performance of glazing used at very high-speeds.
To resolve this issue, the group considered existing international
standards and test procedures. In particular, the group focused on the
development of criteria, test conditions, procedures, and projectile
design based on relevant portions of EN 15152 and UIC 651.
    After considerable discussion, the task group reached consensus to
adopt

modified criteria based on the relevant elements of EN 15152 and UIC
651 for the Tier III end-facing large object impact test. This is
outlined in proposed paragraph (b)(2), which would establish the
projectile design, test conditions (e.g., speed, impact angle, sample
size, temperature, etc.), the number of representative samples to be
tested, and qualification criteria. Additional considerations for the
use of representative sample sizes, instead of actual dimensions, are
proposed in paragraph (b)(3), and proposed paragraph (b)(4) addresses
demonstration of resistance to spalling. Specifically, under the
conditions proposed, each sample must show no penetration, no marks on
the witness plate, and no failure of the mounting apparatus, which
would be representative of the method by which the glazing would be
installed. Further, under proposed paragraph (b)(4), materials used
specifically to protect the cab occupants from spall (i.e., spall
shields) would not be required to meet the flammability and smoke
emission performance requirements of appendix B to this part. The task
group raised concerns about the availability of spall shields that meet
the performance requirements of appendix B to this part, while
balancing the protection from spalling to cab occupants that spall
shields offer. FRA makes clear, however, that spall shields, like other
materials in a cab, would continue to be subject to other requirements
for fire safety, i.e., the requirements of Sec.  238.103(c) through
(e), which include fire safety analysis requirements.
    In addition, proposed paragraph (b) also identifies supplemental
considerations for the effects of temperature and curvature, each
adopted from EN 15152. These considerations are not expressly detailed
in part 223, yet they were widely accepted as necessary to ascertain
reliable and accurate glazing performance evaluations. The effects of
curvature could not be ignored because most high-speed trainsets now
incorporate sophisticated front-end glazing designs to balance
visibility with aerodynamics. FRA notes that, although the task group
considered a small object impact test, it decided such a requirement
was not necessary at this time. The task group considered its value for
high-speed trainsets related more to the durability and maintenance of
the glazing, whereas the large object impact and ballistic test
requirements would provide the more critical performance metrics
related to safety. FRA agrees with the approach taken by the task
group.
    FRA notes that the cab side glazing, addressed in proposed
paragraph (c), presents a different set of challenges and its role in
protecting cab occupants is highly dependent on window size and
location, which can vary greatly between trainset designs. While
initial task group discussions considered adopting traditional Type I
requirements for the side glazing, it determined it was not necessary
and potentially impractical. Imposing the same requirements established
for end-facing glazing would require a substantial increase in size and
weight (and the inherent framing and mounting considerations) and may
limit the level of available protection by potentially restricting the
use of innovative, lightweight transparent materials, which may be well
suited for this side-facing location.
    Since side-facing cab glazing is not directly exposed to hazards in
the direction of travel, the speed-dependent requirements of the
proposed Type IHS test requirements may be inappropriate. The glazing
task group agreed that the two most important performance metrics for
safety in this location are ballistic resistance and mounting strength.
Therefore, the group recommended maintaining the same level of
ballistic protection as currently provided in part 223 for end-facing
glazing as the primary performance metric for side-facing cab glazing.
The task group also agreed to continue the current side-facing large
object impact test in part 223 to ensure the glazing mounting
arrangement would be structurally sufficient. FRA agrees with this
approach.
    Ballistic protection for cab glazing was discussed in detail during
task group meetings. In particular, labor representatives asserted that
ballistic protection from a larger diameter projectile, differing from
the size required for Type I glazing by part 223, would enhance the
overall safety of the cab occupants. Much discussion was focused on
this point, but a review of the available information on the impact
characteristics of reasonable ballistic scenarios (projectile size and
terminal velocity), and a review of the statistics related to glazing
failure due to ballistic impact, proved inconclusive. This is one area
where the task group could not agree on a consistent approach.
Therefore, the task group referred the decision on ballistic
requirements for cab glazing to FRA during the development of the task
group's final recommendations.
    FRA does not have sufficient evidence to suggest a particular risk
or hazard exists that would apply to all potential Tier III systems to
warrant a change from current ballistic requirements in part 223.
However, this does not imply that the conditions of a particular
operation may not warrant additional consideration and protection. To
be consistent with the aforementioned approach to Tier III safety,
elements which may be subject to variables present within a specific
operation must be addressed in a manner appropriate to that operation.
Since the level of service, operating environment, and operational
conditions may vary greatly between Tier III railroads, a single
prescriptive requirement that varies from current requirements cannot
be justified.
    Proposed paragraph (b)(5) describes the approach taken for Tier III
ballistic protection. Specifically, Tier III operations must identify
risks and hazards specific to their property as part of their Tier III
Safe Operation Plan, and provide ballistic penetration resistance
sufficient to protect cab occupants from these risks and hazards. This
protection shall, at a minimum, meet the requirements of part 223,
appendix A.
    Proposed paragraph (b)(6) describes options for testing of glazing
for Tier III trainsets. Compliance with the requirements may be
demonstrated by independent third-party testing or by the glazing
manufacturer itself. If the glazing manufacturer is chosen to certify
the glazing, the manufacturer must invite FRA to witness the test(s)
and provide 30 days' notice to FRA before conducting the test(s).
    Paragraph (b)(7) proposes re-certification requirements that would
apply when changes to the glazing manufacturing process or mounting
arrangement occur which may influence the mechanical properties of the
glazing system, and the ability of the glazing to comply with the
penetration resistance requirements of this section. This proposed
requirement is necessary to ensure that the integrity of the glazing is
not compromised by changes occurring after the original certification.
    Paragraph (b)(8) proposes that documentation describing any glazing
certification or re-certification be made available to FRA upon
request.
    Proposed paragraph (b)(9) describes the marking requirements for
Tier III end-facing cab glazing material. Markings must be clearly
visible after the glazing is installed and contain the words ``FRA TYPE
IHS'' (indicating that the glazing is compliant with the requirements
in this paragraph (b)), the

name of the manufacturer, and the type of brand identification of the
material.
    As noted above, proposed paragraph (c) contains the requirements
for side-facing exterior cab glazing. Such glazing must comply with the
existing large-object impact requirements for Type II glazing described
in appendix A to part 223 of this chapter. FRA also proposes that side-
facing cab glazing must achieve the same ballistics penetration
resistance required of end-facing glazing in paragraph (b)(5) above.
For all other areas of the trainset, the non-cab side-facing glazing
requirements of paragraph (d) apply. FRA invites comment on the manner
and extent to which glazing subject to the requirements of paragraphs
(c) or (d) should be specifically marked and identified for Tier III
service similar to that proposed for end-facing cab-glazing in
paragraph (b)(9). FRA may impose specific marking and identification
requirements in the final rule.
    The performance aspects of non-cab side-facing glazing were
established by consensus agreement of the ETF before creation of the
Tier III Cab Glazing Task Group. Overall, the requirements for non-cab
glazing maintain the current requirements for Type II glazing in
appendix A of part 223 as indicated in paragraph (d)(1). As mentioned
earlier, FRA intends for this approach to maintain compatibility with
current Tier I requirements to establish commonality for operation with
all other equipment types at speeds not exceeding 125 mph, whereas
additional systemic safety measures and ROW protections would be
required for higher-speed operations.
    In regards to emergency egress and rescue access, the ETF
recognized that multiple approaches would need to be considered to
support the adoption of service-proven technology. More specifically,
the methods employed in the manufacturing of high-speed trainsets are
often governed by considerations of aerodynamic effects and noise
reduction. In some designs, this can have particular influence on the
way side-facing glazing is installed and mounted on trainsets.
Therefore, the ETF recommended a more performance-oriented requirement
rather than a prescriptive one, which is reflected here and in the
proposed requirements for emergency window egress and rescue access in
proposed Sec.  238.741 discussed below. Proposed paragraph (d)(2) would
specifically recognize the design of windows intended to be breakable
as an alternative for removing glazing. This would include using a tool
or other method to expeditiously and safely remove the glazing if at
least the same level of glazing safety is maintained as the current
requirements of part 223. This must be demonstrated by quantitative
analysis, full scale demonstration, or other means and be addressed as
part of the railroad's Tier III Safe Operation Plan. As noted,
requirements for emergency window egress and rescue access would also
need to be met, consistent with proposed Sec.  238.741.
    Proposed paragraph (e) contains requirements for glazing
securement. Paragraph (e)(1) would require designing each exterior
window glazing system (the window glazing and its mounting apparatus)
to withstand the forces caused by variances in pressure when two trains
pass at their maximum authorized speed at their closest distance to
each other. This requirement is identical to that currently provided
for Tier I and Tier II passenger equipment in Sec. Sec.  238.221(b)(2)
and 238.421(d)(1), respectively, and would help provide assurance that
a trainset's exterior window glazing remains in place when passing
other objects in close proximity. Proposed paragraph (e)(2) would also
require that exterior window glazing be secured so as to withstand the
impact forces described in this section. This proposed requirement is
virtually identical to that currently provided for Tier I and Tier II
passenger equipment in Sec. Sec.  238.221(b)(1) and 238.421(d)(2),
respectively. The requirements proposed in paragraph (e) are common for
all exterior glazing installed on a Tier III trainset, and may be
demonstrated through testing or analysis.
Brake System
Section 238.731 Brake System
    In this section, FRA is proposing to introduce requirements for
brake systems for Tier III passenger trainsets. Development of these
requirements was identified as one of the goals for this first Tier III
rulemaking to facilitate planned equipment acquisitions. These
requirements represent a balance between maintaining compatibility with
existing Tier I equipment and the adoption of service-proven techniques
to protect against potential risks encountered with high-speed
operations. A concerted effort was made to develop technology-neutral
requirements.
    To develop the proposal for these brake system requirements, the
ETF created the BTG. The BTG's charter, established at the group's
initial meeting, was to develop performance-based regulations which
would accommodate existing high-speed trainset technology without
regard to its design. To achieve this goal, many of the provisions in
this proposed section refer to provisions in the railroad's Tier III
Safe Operation Plan or ITM plan. This is necessary to address the
various ways brake system technology is actually implemented in high-
speed passenger trainsets worldwide.
    Proposed paragraph (a) describes the requirement for each railroad
to identify (through analysis and testing) the maximum safe operating
speed for its Tier III trainsets that results in no thermal damage to
equipment or infrastructure during normal operations. This is based on
the requirements for Tier I and Tier II passenger equipment in
Sec. Sec.  238.231(j)(4) and 238.431(e)(4), respectively, that a train
not operate at a speed resulting in thermal damage to wheels or rotor
surface temperatures exceeding the manufacturer's recommendation when
the friction brake alone is applied to brake the train. Nonetheless,
this proposed section acknowledges that, at present, high-speed
trainset braking technology relies predominantly on electric (i.e.,
dynamic or regenerative) braking and that friction braking, by whatever
means, is used only at lower speeds. In addition, this proposed section
presumes there are extensive on-board diagnostics capable of
identifying dynamic brake defects (as specified in Sec.  238.731(n))
present. Moreover, this proposed section extends the scope of existing
regulations by considering the potential for a Tier III braking
technology that relies on interaction or contact with the rail or
guideway.
    Proposed paragraph (b) would require the railroad's Tier III Safe
Operation Plan to identify the worst-case adhesion conditions under
which the brake system must stop the passenger trainset from its
maximum operating speed within the prevailing signal spacing. This
proposed requirement is derived from its Tier II equivalent at Sec.
238.431(a), which states that a passenger train's brake system shall be
capable of stopping the train from its maximum operating speed within
the signal spacing existing on the track over which the train is
operating under worst-case adhesion conditions. The distinction for
Tier III is that the ``worst case'' conditions would be defined by a
railroad in its Tier III Safe Operation Plan. This would help ensure
that a railroad relies on a formally-devised definition of worst-case
adhesion in its procurement of individual equipment. In recognizing
that these elements may vary between operations and geographical
locations, allowing a railroad to define these conditions

would provide it the flexibility to tailor its braking system to the
actual operating environment.
    Proposed paragraph (c) would require Tier III trainsets to be
equipped with an emergency brake application feature that is available
at any time and produces an irretrievable stop. This proposed paragraph
is consistent with the requirements of Sec.  232.103(i) of this chapter
for brake systems generally and the requirements of Sec.  238.231(c)
and Sec.  238.431(c) for Tier I and II passenger equipment brake
systems, respectively. The emergency brake application would also be
initiated by an unintentional parting of the train, or by the train
crew at locations specified in the railroad's Tier III Safe Operation
Plan. Because the locations where a trainset can be safely stopped are
operation-specific, the railroad would identify them in its Tier III
Safe Operation Plan.
    Proposed paragraph (d) would establish requirements for a passenger
brake alarm. The BTG invested considerable effort addressing this
concept. Generally, the passenger brake alarm enables passengers to
alert the engineer of a need to stop the train. However, stopping the
train at a random location due to a passenger-initiated brake command
can be a highly undesirable event and the BTG believed the engineer
should determine the safest location where the train should stop under
emergency conditions. Thus, the BTG recommended a set of conditions
when the passenger brake alarm is acknowledged and acted upon, which
FRA agrees it should adopt for Tier III passenger equipment. Generally,
these provisions have been developed in consideration of operating
practices associated with present-day high-speed operations in Asia and
Europe and relevant requirements currently in part 238.
    Proposed paragraph (d)(1) would specify that each trainset unit
have two locations equipped with the means to initiate a passenger
brake alarm unless a unit is 45 feet or less in length. In that case,
one equipped location would be sufficient.
    This proposal also derives from the requirements for Tier II
passenger equipment in Sec.  238.431(c). Passenger brake alarm
locations would be identified in the railroad's Tier III Safe Operation
Plan. This paragraph would also require that the words ``Passenger
Brake Alarm'' be legibly stenciled or marked on each device or on an
adjacent badge plate, as required for Tier I passenger equipment in
Sec.  238.305(c)(5) (as ``Emergency Brake Valve'') and indirectly
required for Tier II passenger equipment under subpart F of part 238.
    Proposed paragraph (d)(2) would require the passenger brake alarm
to be designed to minimize the opportunity for accidental activation.
The brake alarm may be protected from accidental activation by a cover
or screen provided the alarm remains readily accessible to passengers.
    Proposed paragraph (d)(3) would require that activation of the
passenger brake alarm result in an emergency brake application if the
trainset has not cleared the boarding platform. This proposal
recognizes in particular that the alarm may be activated due to an
urgent safety issue associated with passengers or crewmembers boarding
or alighting from the trainset while at the platform, and that the
trainset would be traveling at a slower speed as it begins to
accelerate away from the platform.
    Proposed paragraph (d)(4) would specify the sequence of events when
the passenger brake alarm is activated after the trainset has cleared
the boarding platform. In this event, the engineer must acknowledge the
alarm within a prescribed time period to retain control of the
trainset. The railroad's Tier III Safe Operation Plan must specify the
time period the engineer has to act, and the Plan must also describe
the method used to confirm that the trainset has cleared the boarding
platform.
    Proposed paragraph (d)(5) would describe the brake system operation
when the engineer does not acknowledge a passenger brake alarm with the
specified time period. In this event, a full service brake application
shall occur automatically unless the engineer intervenes by
acknowledging the brake alarm and actively manipulating appropriate
trainset controls, as described in proposed paragraph (d)(6), to give
the engineer ultimate control over whether to stop the trainset.
    Proposed paragraph (e) addresses degraded brake system performance
of Tier III trainsets with blended braking systems and is based on
requirements for Tier I and Tier II passenger equipment in Sec. Sec.
238.231(j) and 238.431(e), respectively. A blended brake system
consists of a combination of friction and dynamic braking. Proposed
paragraph (e)(1) specifies that the allowable stopping distance defined
in the railroad's Tier III Safe Operation Plan shall not be exceeded in
the event of a power loss or failure of the dynamic or regenerative
brake. The Tier III Safe Operation Plan must contain provisions for
reducing the maximum allowable train speed, based on feedback from the
on-board monitoring and diagnostic system, specified in proposed Sec.
238.731(n), so the train can be safely stopped using friction braking
alone within the allowable stopping distance.
    Proposed paragraph (e)(2) would require the railroad's Tier III
Safe Operation Plan to define the operating conditions when the
available friction braking effort alone can safely stop the Tier III
trainset. As a whole, proposed paragraph (e) would require that
restrictions be in place (as defined in the Tier III Safe Operation
Plan) that prescribe how trainsets without functional electric braking
are to be operated to ensure thermal-related damage does not occur,
particularly to brake equipment.
    Proposed paragraph (e)(3) would require each Tier III trainset to
be equipped with diagnostic hardware and software that provides a
continuous indication of the brake system status to the engineer in the
controlling cab. See also the proposed requirement in Sec.  238.731(n)
for an onboard monitoring and diagnostic system.
    Proposed paragraph (e)(4) would require the railroad to determine,
through analysis and testing, the maximum speed its Tier III trainsets
can operate at using the friction brake system alone without causing
thermal-related damage to the equipment or infrastructure. This
provision is related to proposed paragraphs (e)(1) through (3) of this
section because the parameters associated with continued trainset
operation under conditions of degraded brake system performance must be
developed for the particular trainset technology and operating
characteristics, and accommodated in trainset operating procedures,
including any software and hardware associated with trainset speed
control.
    Proposed paragraph (f) addresses main reservoirs for Tier III
trainset brake systems and is generally based on safety requirements
originally developed for steam locomotives, as found in Sec.  230.72(b)
of this chapter. Paragraph (f)(1) would require that main reservoirs be
designed and tested using a recognized industry standard specified in
the railroad's Tier III Safe Operation Plan, such as the American
Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code
for Unfired Pressure Vessel Section VIII, Division I (ASME Code),
referenced in Sec.  229.51(a)(2). The actual standard used to qualify
main reservoirs for Tier III trainsets must be documented in the
railroad's Tier III Safe Operation Plan. This paragraph would specify
the working pressure and rated temperature for main reservoirs unless
otherwise defined by the designated standard

identified in the railroad's Tier III Safe Operation Plan. Reservoirs
would be certified consistent with requirements based on size and
volume.
    Proposed paragraphs (f)(2) and (3) of this section contain
requirements for welded steel main reservoirs that are also based on
requirements originally developed for steam locomotives in Sec.
230.72(b) through (d) of this chapter. Proposed paragraph (f)(3) would
prohibit welded repairs of Tier III trainset main reservoirs.
    Proposed paragraph (g)(1) addresses requirements specifically for
aluminum main reservoirs and refers to the existing requirements in
Sec.  229.51(a) of this chapter applicable to locomotives.
    Proposed paragraph (g)(2) is a new provision and contains a
prohibition on welded repairs to aluminum main reservoirs.
    Proposed paragraph (h) prescribes requirements for steel and
aluminum main reservoir proof tests, which would be performed prior to
their installation on a Tier III trainset. These tests may be pneumatic
or hydrostatic. The test pressure would be defined in paragraphs (f) or
(g) of this section, depending on whether the reservoir is steel or
aluminum, unless otherwise established by the railroad's ITM Plan.
Records of main reservoir tests must be made and retained for the life
of the equipment. In addition, the railroad's ITM Plan shall define
periodic inspection requirements for main reservoirs on Tier III
trainsets.
    Proposed paragraph (i) addresses the requirements for the locations
of gauges and devices used by the engineer to aid in the control or
braking of a Tier III trainset. Such devices must be placed so that the
engineer can conveniently read them from the engineer's normal position
during trainset operation. This paragraph is based on the existing
requirement in Sec.  229.53 of this chapter.
    Proposed paragraph (j) contains requirements for Tier III trainset
brake application and release. Paragraph (j)(1) proposes that brake pad
and shoe clearance must be present when the brakes are released.
Paragraph (j)(2) would require establishing the minimum brake cylinder
pressure necessary to adjust from minimum service to full service brake
application for proper train operation. This pressure would be approved
during the trainset design review and documented in the railroad's Tier
III Safe Operation Plan.
    Proposed paragraph (k) would require that the railroad specify the
ITM requirements for the foundation brake gear in the railroad's ITM
plan. The purpose for these requirements derives from Sec.  229.57 of
this chapter. However, due to the variety of possible Tier III braking
systems, the prescriptive requirements of Sec.  229.57 may not be
appropriate for a given foundation brake system. Defining the
requirements in the railroad's ITM plan, which is subject to FRA review
and approval, would ensure that appropriate ITM practices are in the
foundation brake system on Tier III trainsets.
    Proposed paragraph (l) would define limits on brake pipe leakage
and also require that the method for inspecting brake pipe leakage be
prescribed in the railroad's ITM plan. Leakage rates would be
established under either paragraph (l)(1) or paragraph (l)(2) of this
section, whichever is more restrictive. Specifically, paragraph (l)(1)
would permit leakage limits based on an Air Consumption Analysis in the
railroad's Tier III Safe Operation Plan. Paragraph (l)(2) would set
prescriptive requirements for brake pipe leakage adopted from Sec.
229.59(b) and (c) of this chapter.
    Proposed paragraph (m) describes the requirements for wheel slide
protection and alarm. Extensive discussion on this topic occurred
during BTG deliberations. For safety reasons, wheel slide must be
avoided to prevent overrunning a switch or incursion of the trainset
into an area beyond the confines of its operating authority.
Nonetheless, the BTG considered wheel slip to be a maintenance concern
and did not recommend that FRA address it in this proposed rulemaking.
Wheel slip differs from wheel slide because it is caused when the
tractive effort on the wheel exceeds the adhesive forces keeping the
wheel in normal rotational contact with the rail, whereas wheel slide
is caused when the braking effort on the rail exceeds the adhesive
forces keeping the wheel in normal rotational contact with the rail.
FRA agrees with the task group and has modeled this paragraph after the
wheel slide protection and alarm requirements for Tier II passenger
equipment in Sec.  238.431(h).
    Proposed paragraphs (m)(1) through (3) of this section define the
minimum functional requirements for wheel slide protection and alarm.
Paragraph (m)(1) would require that an adhesion control system be
available to adjust the braking force on each wheel to avoid wheel
slide. Paragraph (m)(2) would require that this system be able to alert
the engineer, either through visible or audible means, or both, of the
presence of a wheel slide condition on any axle in the trainset.
Proposed paragraph (m)(3) would address when the wheel slide protection
system fails to function within pre-established, allowable parameters
as defined in the railroad's Tier III Safe Operation Plan. To prepare
for such an event, the Tier III Safe Operation Plan shall specify
operating restrictions (e.g., speed limits) on trainsets whose slide
protection devices are not functioning as intended.
    Proposed paragraph (n) would require each Tier III trainset to be
equipped with a brake system health monitoring and diagnostic system to
automatically assesses the functionality of the brake system for the
entire trainset, both before departure of the trainset and while it is
en route. The railroad's Tier III Safe Operation Plan shall document
the details of the monitoring and diagnostic system and the means for
communicating trainset brake system functionality.
    Proposed paragraph (o) would require Tier III equipment to be
equipped with a way to secure equipment, when unattended, from
unintentional movement. This means of securement must be independent of
the pneumatic brake. Since the securement technique may be technology-
specific to the trainset, FRA expects the Tier III Safe Operation Plan
would identify the procedures and means necessary for securing
unattended equipment and the grade conditions when such securement must
occur. The Tier III Safe Operation Plan shall also provide evidence
demonstrating the effectiveness of the securement method(s). As defined
in Sec.  238.231(h)(4), ``unattended equipment'' means equipment left
standing and unmanned in such a manner that a qualified person cannot
readily control the brake system of the equipment. FRA notes in
particular that, because certain brake system requirements are imposed
by Federal statute, 49 U.S.C. ch. 203, the railroad must also ensure
those statutory requirements are addressed.
    Proposed paragraph (p) would require the design of a Tier III
trainset to accommodate coupling to a rescue vehicle (which could be a
conventional locomotive) or a rescue trainset. The design must also
allow the rescue vehicle or trainset to control the brake system on the
disabled Tier III trainset. This proposed paragraph is based on a
similar requirement for Tier II passenger equipment in Sec.
238.431(f).
Interior Fittings and Surfaces
Section 238.733 Interior Fixture Attachment
    This proposed section would address requirements for interior
fixture attachment strength for Tier III trainsets, principally to help
prevent and mitigate hazards associated with secondary collisions
(i.e., a collision occurring

inside the trainset as a consequence of a (primary) collision involving
external contact with the trainset). It would provide two means of
demonstrating compliance.
    Proposed paragraph (a)(1) would provide the first means: Interior
fixtures must comply with the existing requirements in 49 CFR 238.233,
Interior fittings and surfaces, and APTA PR-CS-S-006-98, Rev. 1
(previously designated as SS-C&S-006), ``Standard for Attachment
Strength of Interior Fittings for Passenger Railroad Equipment,''
Authorized September 2005. FRA proposes to incorporate by reference
this APTA standard into this paragraph and in paragraph (i) of appendix
G to this part. APTA PR-CS-S-006-98 addresses fittings used in commuter
and intercity railcar and locomotive cab interiors. It specifies the
minimum strength and attachment strength for interior sub-systems,
including overhead luggage racks, stanchions and handholds, windscreen
and partitions, food service equipment, and miscellaneous interior
fittings. This standard also contains recommendations for design
requirements and design practices for such interior sub-systems. APTA
PR-CS-S-006-98 is reasonably available to all interested parties online
at www.apta.com. Additionally, FRA will maintain a copy available for
review.
    These proposed requirements are based on the applied accelerations
of 8g longitudinally, 4g laterally, and 4g vertically, acting on the
mass of the fitting (8g/4g/4g). As described in the Technical
Background and Overview section of this NPRM, the 1999 Passenger
Equipment Safety Standards final rule (64 FR 25540) established these
acceleration-based performance requirements after years of industry
practice designing interior fittings to withstand the forces due to
accelerations of 6g longitudinally, 3g laterally, and 3g vertically
(6g/3g/3g), which FRA found to be inadequate to protect against
occupant injury. Subsequent accident investigations have revealed that
interior fixtures that comply with these requirements, codified for
Tier I passenger equipment in Sec.  238.233, perform significantly
better than interior fixtures in passenger cars that were exempted from
those requirements and thus do not meet the regulations, i.e.,
generally passenger cars already in service when the 1999 final rule
took effect.
    However, FRA recognizes some Tier III passenger equipment may not
experience accelerations of 8g/4g/4g during the dynamic collision
scenario proposed in Sec.  238.705, or at higher-speed collisions
resulting in collapse of the occupied volume. Members of the rail
industry contend the 8g/4g/4g requirements are unnecessary for some
equipment designed to alternative standards and would add to vehicle
weight. FRA acknowledges that equipment that does not experience large
decelerations during collisions may not need to be designed to these
FRA requirements, which are also reflected in industry safety
standards. Accordingly, FRA developed an alternative attachment
strength option consistent with international design standards.
    Proposed paragraph (a)(2) describes the alternative option for
demonstrating adequate attachment strength of interior fixtures in Tier
III trainsets. The proposed option requires that interior fixture
attachment strength comply with the requirements in Section 6.1.4,
``Security of furniture, equipment and features,'' of GM/RT2100, which
FRA proposes to incorporate by reference in this paragraph and Sec.
238.741(b)(2), below. Section 6.1.4 contains requirements for
securement of furniture, on-board equipment, and other trainset
features to help mitigate against injuries to passengers and crew from
secondary impacts within the occupied volume. GM/RT2100 is available to
all interested parties online at www.rgsonline.co.uk/Railway_Group_Standards. Additionally, FRA will maintain a copy
available for review.
    Certain restrictions govern the option to apply the GM/RT2100
standard. GM/RT2100 is a safety standard that applies to trains
operating in the U.K. The standard mandates requirements for the design
and integrity of rail vehicle structures, including interior fixtures.
The standard requires rail vehicle body structures to comply with the
requirements in EN 12663 and EN 15227. The interior fixture attachment
strength requirements in GM/RT2100 are consistent with the carbody
deceleration limits in EN 12663 and EN 15227.
    The structural carbody requirements of particular relevance in EN
12663 specify minimum proof loads for equipment attachment during
normal operation of the vehicle. The mass of the fixture is multiplied
by specified accelerations. For passenger coach cars, the accelerations
in the longitudinal, lateral, and vertical directions are 5g, 1g, and +3/-1g, as stated in Section 6.5.2,
Tables 13, 14, and 15 respectively.
    The structural carbody requirements of particular relevance in EN
15227 are associated with a dynamic collision scenario (Section 5,
Table 2), in which the mean longitudinal vehicle decelerations in the
survival spaces for power cars and coach cars are limited to 5g for a
36 kph (22.4 mph) collision with a like train (Section 6.4.1).
    If the option to use GM/RT2100 is exercised to demonstrate adequate
attachment strength of the interior fixtures in Tier III trainsets,
then data must be provided to demonstrate that the average longitudinal
deceleration of the CG of each vehicle during the dynamic collision
scenario does not exceed 5g in any 100-ms time period. Suitable
evidence would include a plot of the 100-ms running average
deceleration versus time for the duration of the collision scenario.
The average deceleration over a 100-ms time period is necessary to
account for large decelerations higher than the mean deceleration for
sustained periods (i.e., any period lasting more than 100 ms), which
could result in interior fitting attachment failure. Without suitable
evidence, there is no assurance the less stringent 5g attachment
strength requirement is adequate for the particular trainset under
evaluation. If the adequacy of the attachment strength is not
demonstrated, then the GM/RT2100 option cannot be used and the
crashworthiness of interior fittings must comply with the current Tier
I requirements in Sec.  238.233 and APTA standard PR-CS-S-006-98.
    In addition, if the option to comply with GM/RT2100 is exercised,
then this proposed paragraph would require that interior
crashworthiness be evaluated based on a minimum lateral acceleration of
3g--not the 1g permitted in GM/RT2100. FRA has never found the 1g
lateral acceleration requirement adequate for the U.S. rail operating
environment. Thus, the proposed rule would increase the minimum lateral
acceleration requirement to 3g. Further, the use of the GM/RT2100
standard must be carried out consistent with any conditions identified
in the railroad's FRA-approved Tier III Safe Operation Plan. The Tier
III Safe Operation Plan must demonstrate that interior fixtures provide
an equivalent level of safety during accidents at any speed as
equipment that complies with the requirements in Sec.  238.233 and APTA
PR-CS-S-006-98. The Tier III Safe Operation Plan must address the
collision consequences associated with interior fixtures designed to
withstand acceleration forces of 5g longitudinally, 3g laterally, and
3g vertically (5g/3g/3g) as opposed to 8g/4g/4g. FRA is concerned that
interior fixtures designed to withstand average decelerations of less
than 5g may not have a sufficient factor of safety to remain attached
during collisions

occurring at speeds above the collision design scenario speeds.
Accordingly, some evidence must be provided to ensure that the interior
fixtures do not detach during collisions at speeds above the collision
design scenario speeds, or the likelihood of higher speed collisions
has been significantly reduced to provide the same degree of risk for
equipment whose interior fixture attachments have been designed to
withstand 8g/4g/4g loading.
Section 238.735 Seat Crashworthiness (Passenger and Cab Crew)
    Proposed paragraph (a) contains the requirements for passenger
seating crashworthiness in Tier III trainsets. As in Sec.  238.733
above, FRA proposes two ways to demonstrate adequate attachment
strength.
    Proposed paragraph (a)(1) provides the first means: Passenger
seating must meet the requirements of Sec.  238.233 and APTA PR-CS-S-
016-99, Rev. 2 (previously designated as SS-C&S-016, Rev. 2),
``Standard for Passenger Seats in Passenger Rail Cars,'' Authorized
October 2010. FRA proposes to incorporate this APTA standard by
reference into this paragraph and paragraph (j) of appendix G to this
part. APTA PR-CS-S-016-99 addresses design guidelines, recommendations,
and requirements for passenger seats installed in passenger equipment
that is part of the general railroad system of transportation. APTA PR-
CS-S-016-99 is available to all interested parties online at
www.apta.com. Additionally, FRA will maintain a copy available for
review. However, the rule would not require compliance with section 6.0
of this APTA standard, ``Seat durability testing.'' Seat durability
testing is beyond the scope of this proposal because the testing
focuses on the optimal life of the seats--not their crashworthiness
performance.
    Proposed paragraph (a)(2) describes the second way to demonstrate
compliance. This proposed option explains that passenger seating may
comply with the requirements in Section 6.2, ``Seats for passengers,
personnel, or train crew,'' of GM/RT2100, which FRA proposes to
incorporate by reference into this paragraph. Section 6.2 contains
design specifications and tolerances for passenger and crew seating.
GM/RT2100 is available to all interested parties online at
www.rgsonline.co.uk/Railway_Group_Standards. Additionally, FRA will
maintain a copy available for review.
    The option proposed in paragraph (a)(2) offers alternative test
conditions and performance requirements for evaluating seat
crashworthiness. The applicable dynamic seat test procedures are
defined in appendix E to GM/RT2100. GM/RT2100 utilizes Hybrid III 50th-
percentile male anthropomorphic test devices (ATDs), and the procedures
to prepare the ATDs are defined in appendix G to GM/RT2100. The
applicable injury criteria and survival space requirements are defined
in appendix H to GM/RT2100. Further, the test conditions and
performance requirements in GM/RT2100 are aligned with the structural
design requirements in EN 12663 and EN 15227, whereas the seat test
conditions and performance requirements in APTA PR-CS-S-016-99, Rev. 2,
are aligned with the structural design requirements in subpart C of
part 238.
    Nonetheless, please note that if paragraph (a)(2) is used for
demonstrating compliance with the seat crashworthiness requirements,
then this proposed paragraph would require that interior
crashworthiness be evaluated based on a minimum lateral acceleration of
3g--not 1g as permitted in GM/RT2100. As noted above, FRA found the 1g
lateral acceleration requirement inadequate. Thus, the proposed rule
would increase the minimum lateral acceleration requirement to 3g.
Moreover, the use of the GM/RT2100 standard must be carried out
consistent with any conditions identified in the railroad's FRA-
approved Tier III Safe Operation Plan. The Tier III Safe Operation Plan
must demonstrate that interior fixtures provide an equivalent level of
safety during accidents at any speed as equipment that complies with
the requirements in Sec.  238.233 and APTA PR-CS-S-006-98. For further
discussion of these requirements, see the discussion in Sec.  238.733,
above.
    Proposed paragraph (b) describes the requirements for the
crashworthiness of seats provided for an employee in the cab of a Tier
III trainset. Unlike passenger seating, cab seats must comply with the
requirements in Sec.  238.233(e), (f) and (g), and the performance,
design, and test criteria of AAR-RP-5104, ``Locomotive Cab Seats,''
April 2008, which FRA proposes to incorporate by reference in this
paragraph and paragraph (k)(2) of appendix G to this part. (This AAR
publication is found in Section M of AAR's ``Manual of Standards and
Recommended Practices.'') FRA is not proposing an optional alternative
compliance demonstration. AAR-RP-5104 covers the performance and design
requirements and performance tests for the construction of locomotive
cab seats on road locomotives. AAR-RP-5104 is available to all
interested parties online at www.arrpublications.com for a fee.
Additionally, FRA will maintain a copy available for review.
Section 238.737 Luggage Racks
    Proposed paragraph (a) contains requirements to constrain the
longitudinal and lateral motion of articles stowed in luggage racks.
FRA intends for these proposed requirements to maintain luggage
accessibility while minimizing the risk of hazardous projectiles. The
proposed transverse dividers are intended to limit the longitudinal
motion of luggage not only in collisions but also during normal
operations. In this regard, the proposed downward slope (from the aisle
to the adjacent side-wall) of luggage racks is principally intended to
restrain the lateral motion of luggage during normal operations. By
inhibiting the distance stowed articles may move, the velocity of such
items due to longitudinal and lateral train accelerations is minimized,
which also minimizes their associated kinetic energy when striking
another object.
    Proposed paragraph (b) describes two ways to comply with the
structural requirements for luggage racks. The first, in paragraph
(b)(1), is to comply with Sec.  238.233 as provided for other interior
fixtures. The second, in paragraph (b)(2), is to comply with Section
6.8, ``Luggage stowage'' of GM/RT2100, which FRA proposes to
incorporate by reference in this paragraph. Section 6.8 contains the
requirements for luggage stowage, either on the floor or in overhead
racks. As noted above, GM/RT2100 is available to all interested parties
online at www.rgsonline.co.uk/Railway_Group_Standards. Additionally,
FRA will maintain a copy available for review. This proposed option
offers alternative performance requirements for evaluating luggage
racks. The luggage attachment strength requirements in GM/RT2100 are
aligned with the structural design requirements in EN 12663 and
EN15227, whereas the luggage rack attachment strength requirements in
Sec.  238.233 are aligned with the structural design requirements of
subpart C of this part. A discussion of these requirements is in Sec.
238.733 and in the Technical Background and Overview section of this
NPRM above.
Emergency Systems
Section 238.741 Emergency Window Egress and Rescue Access
    Section 238.741 proposes requirements for emergency egress and
rescue access through windows or alternative openings in passenger cars
as

part of an emergency window egress and rescue access plan for Tier III
trainsets. The ETF recognized that any regulation would need to allow
multiple approaches to facilitate the adoption of service-proven, high-
speed trainset technology. Specifically, the methods used to
manufacture high-speed trainsets are often governed by consideration of
the effects of aerodynamics and noise; and together with the potential
need to pressurize occupied compartments, these can have a particular
effect on the way window glazing is installed and mounted in some
trainset designs. Therefore, the ETF decided to recommend performance-
oriented requirements to allow necessary flexibility where an
appropriate safety case can be made.
    FRA agrees with the ETF's recommendation. Proposed paragraph (a)
would allow a railroad to submit an emergency window egress and rescue
access plan during the design review stage for FRA approval if the
trainset design is not compatible with the emergency system
requirements of Sec. Sec.  238.113 and 238.114. A railroad may elect to
employ an alternative feature or approach that demonstrates an
equivalent or superior level of safety. Such an approach might involve
use of an emergency egress window panel/door exit similar to the over-
wing exits on aircraft and sharing characteristics of a removable panel
for vestibule and other interior doors intended for passage through a
passenger car, as required by Sec.  238.112(f), rather than an
emergency window exit per se.
    In addition, proposed paragraph (b) specifically addresses the
performance of emergency window exits in Tier III trainsets in terms of
ease of operability (e.g., removal). Specifically, paragraph (b)
recognizes that alternative removal methods may need to be employed for
these types of trainsets. Thus, it would allow alternative methods to
remove window glazing, such as use of a conspicuously identified tool,
or other mechanism, to expeditiously and safely remove the glazing. The
emergency window egress and rescue access plan must document that any
alternative method employed is as safe as that provided by the
emergency window exit ease of operability requirements in Sec.
238.113(b). In addition, the railroad must include a provision in its
Tier III ITM plan to inspect for the presence of the identified tool or
other mechanism at least each day the trainset is in service.
    FRA notes that requirements for the ease of operating rescue access
windows are provided in Sec.  238.114(b). As applied to Tier III
trainsets, this paragraph would require that each rescue access window
(or its alternative) be capable of removal without unreasonable delay
by an emergency responder using either a provided external mechanism,
or tools or implements commonly available to the responder in a
passenger train emergency. FRA believes these existing requirements are
broad enough to apply to Tier III trainsets and alternative rescue
access windows if utilized under an approved emergency window egress
and rescue access plan.
    Proposed paragraph (c) addresses window opening dimension
requirements for both emergency egress and rescue access windows in
Tier III trainsets. If the dimensions of window openings do not comply
with the minimum requirements in Sec. Sec.  238.113 or 238.114, then
the emergency window egress and rescue access plan must demonstrate use
of window openings of different dimensions provides at least an
equivalent level of safety. This proposed paragraph acknowledges the
size of windows may vary greatly between designs and not necessarily
reflect the types of windows found on traditional Tier I passenger
cars. Proposed paragraph (d) specifically addresses the use of
emergency egress panels or additional door exits in the alternative to
emergency window exits or rescue access windows. The railroad would be
required to submit a plan demonstrating the means of emergency egress
or rescue access employed provides an equivalent, or superior,
evacuation time for the same number of occupants, as a layout of
comparable size and configuration consistent with Sec. Sec.  238.113 or
238.114, or both, as appropriate. The plan would also address the
location, design, and signage and instructions for the alternative
emergency evacuation openings. As discussed in paragraph (a), FRA
recognizes that railroads may need to employ alternative features or
approaches for evacuating passenger car occupants in Tier III
trainsets, and one such approach might involve use of an emergency
egress window panel/door exit rather than an emergency window exit per
se.
    FRA makes clear that its approval of any alternative emergency
evacuation arrangement would take into account that emergency window
exits themselves provide a supplementary means of emergency egress in
life-threatening situations, should doors be rendered inaccessible or
inoperable. Accordingly, while door exits serve as the preferred means
of egress in an emergency situation, the railroad would be required to
demonstrate that use of additional door exits, instead of emergency
window exits or rescue access windows, would not diminish safety.
Specifically, the railroad would be required to demonstrate that the
risk of carbody distortion and other such risks that could render the
door exits inoperable or inaccessible would be addressed so that at
least an equivalent level of safety is provided.
Section 238.743 Emergency Lighting
    With one exception, the proposed emergency lighting requirements
for Tier III trainsets would be the same as the existing emergency
lighting requirements of Sec.  238.115 for passenger trainsets, as
stated in proposed paragraph (a). The exception would be for emergency
lighting back-up power systems, permitting alternative crash loadings
instead of the requirements in Sec.  238.115(b)(4)(ii). This proposed
exception is detailed in paragraph (b), under which a railroad may seek
to use the loading requirements defined in Section 6.1.4, ``Security of
furniture, equipment and features,'' of GM/RT2100. In particular, these
loading requirements are the same as those proposed for alternatively
demonstrating adequate attachment strength of interior fixtures in Tier
III trainsets discussed in Sec.  238.733, above. Accordingly, both the
interior lighting fixtures and their emergency back-up power systems
would be subject to the same, proposed alternative loading
requirements. As in proposed Sec.  238.733, use of the alternative
loading requirements would be carried out consistent with any
conditions identified in the railroad's FRA-approved Tier III Safe
Operation Plan.
Cab Equipment
Section 238.751 Alerters
    In this section, FRA proposes to introduce requirements for
alerters for Tier III passenger trainsets. The current requirements for
alerters on Tier I passenger equipment can be found at Sec.  238.237,
and those for Tier II passenger equipment can be found principally at
Sec.  238.447 as well as at Sec.  238.445. The regulatory text in this
proposed section for alerters and in proposed Sec.  238.753 for sanders
was developed by the BTG, which was formed by the ETF to address Tier
III braking requirements. The BTG mandate was to develop performance-
based requirements that would accommodate existing, high-speed trainset
technology without regard to its design. Many of the proposed
requirements for alerters and sanders make reference to the need for
accommodating provisions in the railroad's Tier III Safe Operation
Plan.

This is necessary to accommodate the diversity of high-speed trainsets
and the various ways in which the specified requirements may actually
be implemented. FRA notes that the proposed requirements for alerters
and sanders represent only a portion of the cab equipment provisions
that would be applicable to Tier III passenger equipment. FRA would
specifically address other Tier III cab features in future rulemaking.
    Proposed paragraph (a) would require installation of an alerter in
the operating cab of each Tier III trainset, unless the trainset is
operating in a territory where alternate technology is available to
provide the same functions. This provision is proposed to accommodate
alternate designs and technologies that would address this safety
feature.
    Proposed paragraphs (b) through (d) describe the high-level
functionality that an alerter, if present, must provide. Upon
activation of the alerter, engineer acknowledgment must occur within a
prescribed period of time as defined in the railroad's Tier III Safe
Operation Plan in order for the engineer to remain in control of the
trainset. Failure to acknowledge the alerter within the prescribed time
period would result in the automatic initiation of a retrievable, full
service brake application; the full service brake application would be
recoverable only by intervention of the engineer, who must acknowledge
the alerter and actively issue a command for brake application. These
proposed requirements are consistent with those for Tier I and Tier II
passenger equipment, yet would provide a greater level of specificity.
    As noted, this section would allow use of an alternate technology
to provide the same function(s) as an alerter. If such alternate
technology is used, in whole or in part to provide the required
functionality, proposed paragraph (e) would require the railroad to
conduct a hazard analysis to be included in the railroad's Tier III
Safe Operation Plan. The analysis must demonstrate that the use of any
alternate technology to perform the function(s) of an alerter provides
at least an equivalent level of safety to the function(s) the alerter
would be required to perform.
Section 238.753 Sanders
    In this section, FRA is proposing the introduction of requirements
for sanders for Tier III passenger trainsets. Deliberations of the BTG
included discussion of whether sanders would be present on Tier III
trainset equipment. The BTG decided that since the use of sanders is
not prohibited in any way, proposed regulations should be developed to
accommodate this possibility.
    The current requirements for sanders are in Sec.  229.131 of this
chapter. Sanders represent only a portion of the regulations residing
in 49 CFR part 229, Locomotive Safety Standards, which may be
applicable to Tier III passenger equipment. As noted above, the 229/ITM
Task Group is undertaking the effort to develop Tier III equivalents of
applicable provisions in 49 CFR parts 229 and 238, including
inspection, testing, and maintenance requirements for Tier I and Tier
II passenger equipment, which may be addressed in future FRA
rulemaking(s).
    Proposed paragraph (a) addresses the fact that sanders are not
required for Tier III trainsets, but acknowledges that the railroad's
Tier III Safe Operation Plan may include such requirements. If sanders
are present, they must be operational.
    Proposed paragraph (b) makes use of existing provisions in 49 CFR
part 229, specifically Sec.  229.131(a), (b), and (d) of this chapter,
which address where to apply sand, actions to take when sanders become
inoperative en route, and how to identify equipment with defective
sanders. Nonetheless, the proposed text would make clear that the
requirements of Sec.  229.9, Movement of non-complying locomotives, and
Sec.  229.23, Periodic inspection: General, do not apply. Instead, the
requirements of Sec.  238.17, Movement of passenger equipment with
other than power brake defects, would apply to Tier III trainsets with
defective sanders. Likewise, instead of the requirements of Sec.
229.23, requirements for the periodic inspection of a Tier III trainset
with defective sanders would be defined in the railroad's ITM Plan. In
this regard, proposed paragraph (c) would require the railroad's ITM
plan to specify the overall inspection, testing and maintenance
requirements for Tier III trainsets equipped with sanders.
Subpart I--Inspection, Testing, and Maintenance Requirements for Tier
III Passenger Equipment
    Proposed subpart I would contain ITM requirements for Tier III
passenger equipment. Recommendations for ITM requirements specific to
the brake system were developed by the BTG and would be codified in
Sec. Sec.  238.803, and 238.805. Recommendations for more comprehensive
ITM requirements for Tier III passenger equipment are being developed
by the 229/ITM Task Group for future rulemaking. While these
recommendations are still being developed, FRA envisions that the
requirements of this subpart would be based largely on the existing
requirements for Tier II trainsets in subpart F of this part. This
proposed subpart I therefore serves as a placeholder for additional
requirements that may be proposed.
Section 238.801 Scope
    This section would establish the general applicability of the ITM
requirements specified in this part for an operation that falls within
the definition of Tier III.
Section 238.803 Inspection, Testing, and Maintenance Requirements;
Brake System
    FRA is generally proposing to apply subpart F of this part 238 as
the ITM requirements for brake systems of Tier III trainsets, as
identified in proposed paragraph (a). FRA nonetheless emphasizes in
proposed paragraph (b)(1) that the railroad's ITM plan would be
required to contain a description of an appropriate brake test
equivalent to that of a Class I brake test described in Sec.  238.313.
In addition, FRA proposes exceptions to the application of Sec.
238.15, which would otherwise govern the movement of a Tier III
trainset with a power brake defect, as provided in paragraph (b)(2).
The BTG found these exceptions necessary for Tier III trainsets to
accommodate the advanced technology available on such equipment. FRA
agrees, and they would apply in three specific circumstances.
    First, paragraph (b)(2)(i) proposes an exception to the requirement
in Sec.  238.15 that, in the event of an en route failure that causes
power brakes to be cut out or renders them inoperative, would allow for
the determination of the percentage of operative brakes in a Tier III
trainset to be made by a technological method described in the
railroad's Tier III Safe Operation Plan instead of the walking
inspection required by Sec.  238.15(c)(4)(iv). FRA expects that such a
method would rely on diagnostic equipment on board the trainset,
because visual inspection of the brake system may be difficult due to
the expected aerodynamic features of the body of the trainset.
    Second, to accommodate the variety of braking strategies employed
in the design of Tier III trainsets, in paragraph (b)(2)(ii), FRA
proposes that the formula for computing the percentage of operative
brakes necessary for continued trainset operation in the event of
partial brake system failure en route be provided in the railroad's
Tier III Safe Operation Plan.
    Finally, proposed paragraph (b)(2)(iii) would address
implementation of operating restrictions for Tier III

trainsets, depending on whether they are in a shared right-of-way or
not. When a Tier III trainset is operating in a right-of-way shared
with Tier I passenger equipment or freight equipment, operating
restrictions would be determined by the percentage of operative power
brakes in the trainset based on the requirements of Sec.  238.15. When
a Tier III trainset is operating in a right-of-way exclusively for Tier
III passenger equipment, operating restrictions would be defined in the
railroad's Tier III Safe Operation Plan.
Section 238.805 Periodic Tests; Brake System
    In this section FRA is proposing to specify periodic testing
requirements for brake systems of Tier III trainsets. The proposed
requirements in this section were derived from corresponding
requirements in Sec. Sec.  229.25 and 229.29 of this chapter deemed
relevant to Tier III trainsets by the BTG and represent minimum
requirements with which FRA agrees. To render them appropriate for Tier
III technology, FRA's proposal avoids prescriptive standards and allows
for particular details of the testing requirements (frequency, scope,
etc.) to be determined by the railroad's FRA-approved ITM plan.
Subpart J--Specific Requirements for the Safe Operation Plan for Tier
III Passenger Equipment
    FRA proposes to add and reserve this subpart, which would contain
the requirements for the Safe Operation Plan for Tier III Passenger
Equipment. The actual requirements will be introduced in a subsequent
rulemaking. While certain requirements of this proposed rule do make
reference to the Safe Operation Plan for Tier III Passenger Equipment,
FRA has elected not to include any general requirements for this plan
in this NPRM. The ETF had not discussed such requirements in depth when
FRA prepared this NPRM and FRA seeks the ETF's input on such
requirements before addressing them in a future rulemaking. In the
interim, FRA would work with any proposed Tier III operation to ensure
that the specific requirements referencing a Safe Operation Plan for
Tier III Passenger Equipment are properly addressed and documented.
Appendix B to Part 238--Test Methods and Performance Criteria for the
Flammability and Smoke Emission Characteristics of Materials Used in
Passenger Cars and Locomotive Cabs
    To clarify the application of the floor fire test to Tier III
passenger equipment, FRA proposes to add text to Note 16 of the table
of ``Test Procedures and Performance Criteria for the Flammability and
Smoke Emission Characteristics of Materials Used in Passenger Cars and
Locomotive Cabs'' in paragraph (c) of appendix B to this part. FRA
intends for this addition to address how the floor fire test method
requirements of ASTM E-119-00a would apply to the undercarriage design
common to most high-speed trainsets. Unlike most conventional passenger
equipment, most modern high-speed trainsets employ a material cowling