[Federal Register Volume 76, Number 146 (Friday, July 29, 2011)]
[Rules and Regulations]
[Pages 45436-45453]
[FR Doc No: 2011-19216]

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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. NHTSA-2011-0107]
RIN 2127-AK80

Federal Motor Vehicle Safety Standards; Electric-Powered
Vehicles; Electrolyte Spillage and Electrical Shock Protection

AGENCY: National Highway Traffic Safety Administration (NHTSA),
Department of Transportation (DOT).

ACTION: Final rule; response to petitions for reconsideration.

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SUMMARY: This document responds to petitions for reconsideration of a
final rule issued by this agency on June 14, 2010. This final rule
amended the electrical shock protection requirements to facilitate the
development and introduction of fuel cell vehicles (a type of electric-
powered vehicle) and the next generation of hybrid and battery electric
powered vehicles. This document addresses issues raised in the
petitions for reconsideration relating to the scope and applicability
of the standard, the definitions in the standard, the retention
requirements for electric energy storage/conversion systems, the
electrical isolation requirements, the test specifications and
requirements for electrical isolation monitoring, the state-of-charge
of electric energy storage devices prior to the crash tests, a proposed
protective barrier compliance option for electrical safety, the use of
alternative gas to crash test hydrogen fuel cell vehicles, and a
proposed low-energy compliance option for electrical safety.

DATES: The effective date of this final rule is September 1, 2011 with
optional early compliance.
    Petitions for reconsideration: Petitions for reconsideration of
this final rule must be received not later than September 12, 2011.

ADDRESSES: Petitions for reconsideration of this final rule must refer
to the docket and notice number set forth above and be submitted to the
Administrator, National Highway Traffic Safety Administration, 1200 New
Jersey Avenue, SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: For technical issues: Ms. Shashi
Kuppa, Office of Crashworthiness Standards (telephone:<PHONE_NUMBER>)
(fax:<PHONE_NUMBER>), NVS-113.
    For legal issues: Mr. Jesse Chang, Office of the Chief Counsel
(telephone:<PHONE_NUMBER>) (fax:<PHONE_NUMBER>), NCC-112.
    The mailing address for these officials is: National Highway
Traffic Safety Administration, 1200 New Jersey Avenue, SE., Washington,
DC 20590.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Background--June 14, 2010 Final Rule
II. Petitions for Reconsideration
III. Summary of Revisions to the June 14, 2010 Final Rule
IV. Agency Response and Rationale
    a. Application
    b. Definitions
    c. Electric Energy Storage/Conversion System Retention
    d. Electrical Safety
    e. Electrical Isolation Monitoring
    f. Electric Energy Storage Device State-of-Charge
    g. Physical Barrier Compliance Option for Electrical Safety
    h. Use of Alternative Gas for Testing Hydrogen Fuel Cell
Vehicles
    i. Low-Energy Compliance Option for Electrical Safety
V. Rulemaking Analyses and Notices
VI. Regulatory Text

I. Background--June 14, 2010 Final Rule

    On June 14, 2010, NHTSA issued a final rule which amended the
electrical shock protection requirements of Federal Motor Vehicle
Safety Standard (FMVSS) No. 305, ``Electric-powered vehicles;
electrolyte spillage and electrical shock protection,'' to facilitate
the development and introduction of fuel cell vehicles, a type of
electric-powered vehicle, and the next generation of hybrid and battery
electric powered vehicles (75 FR 33515, NHTSA Docket No. 2010-0021).
The final rule revised the agency's standard regulating electrolyte
spillage and electrical shock protection for electric-powered vehicles
to align it more closely with the April 2005 version of the Society of
Automotive Engineers (SAE) J1766--``Recommended Practice for Electric
and Hybrid Electric Vehicle Battery Systems Crash Integrity Testing.''
    This rule also provided greater flexibility by allowing
manufacturers to meet the requirements of FMVSS No. 305 by designing
their electrically powered vehicles so that, in the event of a crash,
the electric energy storage, conversion, and propulsion systems are
either electrically isolated from the vehicle's chassis or their
voltage is below specified levels considered safe from electric shock
hazards. Since the physiological impacts of direct current (DC) are
less than those of alternating current (AC), the final rule specified
lower electrical isolation requirements for certain DC components (100
ohms/volt) than for AC components (500 ohms/volt).
    In addition, the final rule included new definitions, made changes
to existing definitions of terms used in the standard, changed the
energy storage/conversion device retention requirements, specified a
low voltage option for achieving electrical safety, and required
monitoring of the isolation resistance of DC high voltage sources that
comply with the 100 ohms/volt electrical isolation requirement. The
agency also established an effective date on September 1 in the year
after the final rule was published (or September 1, 2011) with optional
early compliance.

II. Petitions for Reconsideration

    Subsequently, NHTSA received petitions for reconsideration of the
June 14, 2010 final rule from the Alliance of Automobile Manufacturers
(Alliance),\1\ Technical Affairs Committee of the Association of
International Automobile Manufacturers, Inc. (AIAM) \2\ and Honda Motor
Co., Ltd. (Honda). Ford Motor Company (Ford) also presented an analysis
to the agency in support of the Alliance's petition for reconsideration
regarding the issue of electric energy storage system state-of-charge
prior to the crash tests specified in the standard.\3\ In addition, on
December 21, 2010, the Alliance, AIAM, and Honda submitted a joint
letter as supplementary information to their petitions for
reconsideration stating their support for the definitions used in the
draft documents on electrical safety for a forthcoming global technical
regulation (GTR) on hydrogen fuel cell vehicle safety.
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    \1\ The Alliance is a trade association whose members are: BMW
Group, Chrysler Group LLC, Ford Motor Company, General Motors LLC,
Jaguar Land Rover, Mazda, Mercedes-Benz USA, Mitsubishi Motors,
Porsche, Toyota, and Volkswagen.
    \2\ The AIAM petition stated it is a trade association whose
Technical Affairs Committee members include: American Honda Motor
Co., American Suzuki Motor Corp., Aston Martin Lagonda of North
America, Inc., Ferrari North America, Inc., Hyundai Motor America,
Isuzu Motors America LLC, Kia Motors America, Inc., Mahindra &
Mahindra Ltd., Maserati North America, Inc., McLaren Automotive
Ltd., Nissan North America, Inc., Peugeot Motors of America, Subaru
of America, ADVICS North America, Inc., Delphi Corporation, Denso
International America, Inc., and Robert Bosch Corporation. In
January 2011, AIAM was renamed as the Association of Global
Automakers (Global Automakers). Nonetheless, our response to
petitions of the final rule will still refer to AIAM.
    \3\ Ford presented an analysis of the state-of-charge of the
energy storage system prior to the crash tests in a meeting with
NHTSA personnel on May 26, 2010. This presentation was posted to the
Docket No. NHTSA-2010-0021 on September 1, 2010.
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    The petitioners generally sought increased clarity by raising
issues

regarding the definitions, test specifications, and performance
requirements in this rule. Specifically, the petitioners raised
questions regarding the applicability and scope of the standard, the
definitions of terms used, the electric energy storage/conversion
system retention requirements, the electrical isolation requirements,
the requirements and test specifications for electrical isolation
monitoring systems, the electric energy storage device state-of-charge,
the protective barrier as a compliance option for electrical safety,
and the use of alternative gas for testing hydrogen fuel cell vehicles.

III. Summary of Revisions to the June 14, 2010 Final Rule

    This document responds to all the petitions for reconsideration of
the June 14, 2010 final rule. Specifically, this final rule makes the
following changes to the June 14, 2010 final rule:
     Revises the ``Application'' section to indicate that the
standard applies only to vehicles that use high voltage electrical
components for propulsion power rather than to any vehicle that has
high voltage electrical components.
     Clarifies the definitions used in the June 14, 2010 final
rule for electrical isolation, electric energy storage/conversion
system, electric energy storage device, propulsion system, and high
voltage source.
     Adds further clarity by including new definitions for
automatic disconnect, electric energy storage/conversion device,
electrical chassis, and electric power train.
     Revises the application of retention requirements from
energy storage/conversion ``systems'' to energy storage/conversion
``devices.''
     Clarifies the electric energy storage/conversion device
retention requirements to indicate that during and after the test, the
device(s) shall remain attached to the vehicle by at least one
component anchorage, bracket, or any structure that transfers loads
from the device to the vehicle structure and those located outside the
occupant compartment shall not enter the occupant compartment.
     Clarifies the electrical safety requirements to specify
that AC high voltage sources with electrical isolation monitoring
require 500 ohms/volt electrical isolation.
     Specifies the voltage measurement locations for high
voltage sources with and without automatic disconnects in the test
procedures for determining electrical safety.
     Revises the electrical isolation monitoring requirement by
deleting the term ``continuous'' in ``continuous monitoring'' and
including a range in resistance of the external resistor selected in
the test procedure to evaluate the performance of the monitoring
system.
     Clarifies the specification for the state-of-charge of
electric energy storage devices before the crash tests to be at the
maximum state-of-charge in accordance with the vehicle manufacturer's
recommended charging procedures, as stated in the vehicle owner's
manual or on a label permanently affixed to the vehicle, or at 95
percent of the maximum capacity of the electric energy storage device
if no such recommendation is made.
     Revises the regulatory text and Figures 1-5 to utilize the
new terms added to the definitions section.

IV. Agency Response and Rationale

    After reviewing the petitions for reconsideration, NHTSA is
responding to each issue raised by the petitioners as follows.

a. Application

    The June 14, 2010 final rule defined the scope of FMVSS No. 305 by
stating the following in paragraph S3 Application:

    S3. Application. This standard applies to passenger cars, and to
multipurpose passenger vehicles, trucks, and buses that have a GVWR
of 4,536 kg or less, that use electrical components with working
voltages more than 60 volts direct current (VDC) or 30 volts
alternating current (VAC), and whose speed attainable over a
distance of 1.6 km on a paved level surface is more than 40 km/h.

    Both the Alliance and the AIAM noted that in section ``S3
Application'' of the final rule, the agency omitted the word
``propulsion'' and that this was not consistent with the language in
the NPRM.\4\ Both organizations argued that the omission of the word
``propulsion'' could be interpreted to encompass all electrical systems
that are not within the scope of FMVSS No. 305 (e.g. high intensity
discharge (HID) headlamps, engine ignition systems, fuel injectors,
etc).
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    \4\ 72 FR 57266; Notice of Proposed Rulemaking; October 9, 2007.
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    The Alliance proposed that the scope be remedied by adding the word
``propulsion'' in the application section, S3. The AIAM indicated in
its petition that it supported the language proposed by the Alliance.
The language proposed by the Alliance is as follows:

    S3 Application. This standard applies to passenger cars, and to
multipurpose passenger vehicles, trucks and buses with a GVWR of
4536 kg or less, that use electrical propulsion components with
working voltages more than 60 volts direct current (VDC) or 30 volts
alternating current (VAC), and whose speed attainable over a
distance of 1.6 km on a paved level surface is more than 40 km/h.
(emphasis in the original)

    NHTSA's Response: We agree with the Alliance that by omitting the
word ``propulsion'' in S3 of the final rule, the standard encompasses
vehicles and electrical systems that were not intended for application
of FMVSS No. 305. Since the agency is not aware of any cases of
injuries/fatalities from shock in non-electrically powered vehicles
with other high voltage components such as HID headlamps, ignition
systems, or fuel injectors, this final rule adopts the language for S3
Application as proposed by the Alliance. This new version of the
regulatory text ensures that FMVSS No. 305 will not extend to the
aforementioned vehicles and vehicle components for which the standard
was not intended to apply.

b. Definitions

    The June 14, 2010 final rule adopted new definitions into FMVSS No.
305. In a joint letter submitted by the Alliance, AIAM, and Honda, the
organizations acknowledged that while the current FMVSS No. 305
definitions were based on SAE J1766, the subsequent promulgation of
FMVSS No. 305 and the development of an international GTR on hydrogen
fuel cell vehicle safety have largely rendered aspects of the SAE
standard obsolete. The organizations requested that the agency
incorporate, into FMVSS No. 305, the definitions contained in the draft
electrical safety requirements developed by the Electric Safety (ELSA)
working group in September 2010 as part of the draft GTR. Given this
request from the aforementioned organizations, the rapid development of
technology in electrical and fuel cell vehicles resulting in numerous
changes in terminology and their associated definitions, and
significant uncertainty among the relevant stakeholders as to the
proper interpretation of many of the definitions adopted by the June
14, 2010 final rule, today's final rule seeks to clarify and update
many of the definitions through additional language and/or adopting
similar language from the draft ELSA electrical safety document
(henceforth referred to as the ELSA document) where appropriate.\5\ In
the following

sections, we will address each of the definitions added or amended by
today's final rule in turn.
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    \5\ Electrical Safety Provisions for Vehicles Post Crash ELSA-8-
05 Rev. 01 (Draft agreed during 8th ELSA Meeting, Aug 31-Sept 2,
2010) http://www.unece.org/trans/doc/2010/wp29grsp/ELSA-8-05r1e.pdf.
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1. Automatic Disconnect
    One appropriate area for adopting similar language from the ELSA
document is the definition for ``automatic disconnect.'' Since the June
14, 2010 final rule did not define ``automatic disconnect,'' the agency
is concerned that it may result in ambiguity regarding the location of
voltage measurements taken pursuant to paragraph S7.6.1 (as further
discussed later in this document). Therefore, today's final rule
includes a definition for automatic disconnect, derived from the ELSA
document, which states that ``automatic disconnect'' means a device
that when triggered, conductively separates a high voltage source from
the electric power train or the rest of the electric power train.
2. Electrical Isolation
    In the final rule, we defined ``Electrical isolation'' as ``the
electrical resistance between the vehicle high voltage source and any
vehicle conductive structure.'' The Alliance stated that the definition
for ``electrical isolation'' as defined in the final rule could present
difficulties because ``any vehicle conductive structure'' could be
interpreted to include the high voltage source itself, and a high
voltage source cannot be isolated from itself. The Alliance, therefore,
petitioned to revise the definition so that the electrical isolation is
between the vehicle high voltage source and the ``vehicle chassis
electricity-conducting structure.''
    NHTSA's Response: The agency agrees that that the language ``any
conductive structure'' should be clarified to indicate which vehicle
components are required to be isolated from the high voltage source.
However, we decline to adopt the Alliance's proposed term, ``vehicle
chassis electricity-conducting structure,'' since it also lacks
sufficient clarification on which vehicle components will be included
by this term. For example, it is unclear whether the term includes
other conducting structures in the vehicle such as the enclosures of
high voltage sources. To address this issue, this final rule clarifies
what the high voltage source is electrically isolated from by including
a definition for a new term that has been proposed in the draft ELSA
document. Based on the language of the ELSA document, a definition for
``electrical chassis'' is included in today's final rule as follows:

    Electrical chassis means conductive parts of the vehicle whose
electrical potential is taken as reference and which are: (1)
conductively linked together, and (2) not high voltage sources
during normal vehicle operation.

    Since this definition of electrical chassis includes vehicle
designs with multiple electrical chassis, this final rule clarifies the
definition of electrical isolation to mean the electrical resistance
between a given high voltage source and any electrical chassis of the
vehicle. Further, in order to be consistent with the manner in which
electrical isolation is determined in S7.6.6 and S7.6.7 of the
electrical isolation test procedure and with the units of electrical
isolation specified in S5.3(a), today's final rule also clarifies the
definition of electrical isolation of a high voltage source to mean the
electrical isolation resistance of the high voltage source divided by
the working voltage of the high voltage source. Applying these
corrections, along with the new definition of electrical chassis,
today's final rule amends the definition for electrical isolation to
read as follows:

    Electrical isolation of a high voltage source in the vehicle
means the electrical resistance between the high voltage source and
any of the vehicle's electrical chassis divided by the working
voltage of the high voltage source.

    The agency believes the changes made in today's final rule address
the Alliance's concern about the broad term ``any vehicle conductive
structure.'' Specifically, this definition ensures that the term
``vehicle conductive structure'' is not construed to include the high
voltage source itself as the new definition for ``electrical chassis''
explicitly excludes high voltage sources. In addition, the use of these
definitions more closely aligns FMVSS No. 305 with the definitions
proposed by the ELSA working group and clarifies what types of
components would be considered part of the chassis. For example, under
these definitions, the electrical chassis includes the enclosures of
the high voltage sources which are conductively linked to other
conductive parts of the vehicle whose electrical potential is taken as
a reference.
3. Electric Energy Storage/Conversion/Power Generating System &
Electric Energy Storage Device
    Before the NPRM in this current rulemaking, FMVSS No. 305 contained
a definition for the term ``Battery system component.'' In the NPRM,
the agency proposed replacing the definition of ``Battery system
component'' with ``Energy storage system.'' The agency changed the
definition in the final rule after considering the joint Alliance/AIAM
comment to the NPRM to include ``energy conversion system'' as part of
the definition for ``Energy storage system.'' In their comment, the
Alliance/AIAM stated that fuel cell systems were conversion systems and
should also comply with the retention requirements. NHTSA agreed and
redefined ``Energy storage system'' as ``Electric energy storage/
conversion/power generating system.'' The term ``power generating
system'' was also included to align FMVSS No. 305 more closely with the
terminology used in SAE J1766. Thus, the June 14, 2010 final rule
defined ``Electric Energy Storage/Conversion/Power Generating System''
as follows:

    Electric energy storage/conversion/power generating system means
the components comprising, but not limited to, the vehicle's high
voltage battery system, capacitor system, or fuel cell system, and
rechargeable energy storage systems. These include, but are not
limited to, the battery or capacitor modules, interconnects, venting
systems, battery or capacitor restraint devices, and electric energy
storage boxes or containers that hold the individual battery or
capacitor modules. Hydrogen system components of fuel cell vehicles,
such as the hydrogen tanks and hydrogen tubes, are not included in
the electric energy storage/conversion system.

    We received multiple petitions requesting that the agency
reconsider the ``Electric energy storage/conversion/power generating
system'' definition. The Alliance stated that this definition is overly
broad and includes energy storage systems beyond those used for
propulsion power. The Alliance recommended that the definition be
modified to utilize the following text: Electric energy storage/
conversion/power generating system ``means the electric energy sources
for the propulsion system comprising, but not limited to, the vehicle's
high voltage battery system * * *'' (emphasis in original).
    The AIAM and Honda had further concerns about the definition. The
AIAM stated that the definition is not used consistently throughout the
standard or even within the definition itself. For example, the AIAM
noted that the last sentence of the definition for electrical energy
storage/conversion/power generating system (which refers to hydrogen
system components of fuel cell vehicles) is only applicable to the
electric energy storage or conversion system parts of the definition
and not to the power generating system portion. Honda stated that the
combined definition may cause confusion to the reader.
    Further, both the AIAM and Honda stated that various requirements
in

FMVSS No. 305 apply only to portions of the electric energy storage/
conversion/power generating system definition, creating confusion
regarding the applicability of various requirements in the standard.
The AIAM and Honda refer to fuel cell modules as an example of this
potential confusion. They noted that the retention requirements in
S5.2, as written, are applicable only to the electric energy storage
system and electric energy conversion system but are not applicable to
the electric power generating system. According to SAE J1766 (April,
2005), the term ``power generating system components'' is defined as
``the components comprising the high voltage power generating system in
an Electric, Fuel Cell or Hybrid vehicle. These include, but are not
limited to, generators, fuel cell modules, DC/DC converters and
interconnects.'' The AIAM and Honda stated that if the SAE definition
is used to determine the meaning of ``power generating system'' for
purposes of S5.2 retention requirements, it could be concluded that
fuel cell modules are exempt because S5.2 does not list ``power
generating system'' as requiring compliance with the retention
requirements. The AIAM and Honda do not believe that the agency
intended to exclude fuel cell modules from the retention requirements,
considering the potential occupant injury risk in a crash if fuel cell
modules became unattached. For clarity, both the AIAM and Honda
petitioned that the terms ``Electric energy storage system,''
``Electric energy conversion system'' and ``Electric power generating
system'' be defined separately.
    NHTSA's Response: We agree with petitioners that the ``Electric
energy storage/conversion/power generating system'' definition should
be clarified in order to avoid confusion as to the applicability of
various requirements in FMVSS No. 305. In order to accomplish this
task, today's final rule utilizes three separate definitions. First, it
renames and makes adjustments to the language in the ``Electric energy
storage/conversion/power generating system'' definition in order to
reference the components that comprise the entire ``Electric energy
storage/conversion system.'' Second, today's final rule also adds a new
definition for ``Electric energy storage/conversion device'' in order
to help distinguish the instances in which the various requirements of
FMVSS No. 305 are to apply to an entire system as opposed to only
component devices. Finally, this rule also retains the ``Electric
energy storage device'' definition with minor revisions in order to
clarify the instances in which the test specifications of this rule
apply to the electric energy storage devices alone.
    The agency also agrees with the Alliance petition that the
definition for ``electric energy storage/conversion/power generating
system'' should be specific to systems used for vehicle propulsion in
order to distinguish them from other electric energy storage systems
such as the auxiliary battery that is present on many hybrid/electric
vehicles and is currently not subject to the retention requirements
since it is typically of low mass and does not pose a safety hazard in
the existing fleet. Thus, we have made the appropriate modifications to
the three aforementioned definitions to indicate that the devices or
components covered by each definition are used for vehicle propulsion.
    In order to further add clarity to this definition, this final rule
removes the reference to the term, ``power generating systems,'' from
the June 14, 2010 final rule definition of ``Electric energy storage/
conversion/power generating system.'' As ``power generating systems''
was included in the June 14, 2010 final rule definition in order to
more closely align FMVSS No. 305 with the (now obsolete) SAE Standard
J1766, the agency believes that there is no longer a purpose for
including ``power generating systems'' in the ``Electric energy
storage/conversion/power generating system'' definition. Thus, today's
final rule simply defines ``Electric energy storage/conversion
system.''
    In addition, we agree with the AIAM that the last sentence of the
``Electric energy storage/conversion/power generating system''
definition in the June 14, 2010 final rule can cause confusion. We
believe that the last sentence of that definition, which states that
``[h]ydrogen system components of fuel cell vehicles, such as the
hydrogen tanks and hydrogen tubes, are not included in the electric
energy storage/conversion system,'' is superfluous. Thus, in further
advancing the goal of clarity in the ``Electric energy storage/
conversion system'' definition, we have deleted the aforementioned
sentence. Under the definition in today's final rule, fuel cells are a
type of energy conversion system and the agency will continue to refer
to high voltage batteries, capacitors, and fuel cell systems as
``energy storage/conversion systems.''
    Thus, the final rule defines ``Electric energy storage/conversion
system'' as follows:

    Electric energy storage/conversion system means an assembly of
electrical components that stores or converts electrical energy for
vehicle propulsion. This includes, but is not limited to, high
voltage batteries or battery packs, fuel cell stacks, rechargeable
energy storage systems, capacitor modules, inverters, interconnects,
and venting systems.

    Additionally, today's final rule adds a new definition for
``Electric energy storage/conversion device.'' We take note that the
retention requirements of S5.2 of the June 14, 2010 final rule apply to
all components that fall under the broader ``Electric energy storage/
conversion system'' definition and that petitioners asked for
clarification to the ``Electric energy storage/conversion system''
definition, in part, to clarify the specific components that will be
subject to the retention requirements of paragraph S5.2. As further
discussed later in this document, petitioners are concerned that
``energy storage/conversion systems'' can include interconnects and
venting systems that are typically of low mass and need not be included
in the retention requirements because they are not a safety risk. Thus,
to make this distinction, today's final rule modifies paragraph S5.2 to
utilize the definition for ``electric energy storage/conversion
device'' and defines this term as follows:

    Electric energy storage/conversion device means a high voltage
source that stores or converts energy for vehicle propulsion. This
includes, but is not limited to, a high voltage battery or battery
pack, fuel cell stack, rechargeable energy storage device, and
capacitor module.

    Today's final rule also retains and amends the definition of
``Electric energy storage device'' from the June 14, 2010 final rule.
The June 14, 2010 final rule defined ``Electric energy storage device''
as follows:

    Electric energy storage device means a high voltage source that
can store energy, such as a battery or capacitor modules.

    The term, ``Electric energy storage device,'' is used in the
regulatory text to specify the state of charge of electric energy
storage devices before the vehicle crash test. While closely related to
the term ``Electric energy storage/conversion device,'' it does not
encompass conversion devices such as fuel cell stacks. Today's final
rule makes minor revisions to this definition in order to add clarity
and consistency with the two other definitions discussed in this
section by specifying that the electric energy storage devices under
consideration are used for vehicle propulsion. Thus, the definition of
electric energy storage device in today's final rule is amended as
follows:

    Electric energy storage device means a high voltage source that
stores energy for vehicle propulsion. This includes, but is not
limited to, a high voltage battery or battery pack, rechargeable
energy storage device, and capacitor module.

    Paragraphs S1 and S2 of today's final rule have also been amended
to reflect these new definitions.
4. High Voltage Source
    The June 14, 2010 final rule included a definition of ``high
voltage source'' which is reproduced below:

    High voltage source means any electric component that has a
working voltage greater than 30 VAC or 60 VDC.

    The Alliance stated that in common usage, a ``voltage source'' is a
component capable of generating or storing electrical potential energy.
It argued that under the current definition, connectors and wiring
could be construed as voltage sources even though they are not capable
of generating or storing electrical energy. The Alliance petitioned
that the definition of ``high voltage source'' be revised to include
``any electric component that is capable of generating or storing a
voltage greater than 30 VAC or 60 VDC.''
    NHTSA's Response: We agree with the Alliance that the current
definition of ``high voltage source'' should be clarified. However, we
cannot agree with the petitioner's proposal to limit the definition of
high voltage sources to only those components that are capable of
generating or storing electrical energy. Through the definition
included in the June 14, 2010 final rule, the agency did intend to
apply the electrical safety requirements to high voltage components,
including wiring and connectors that are part of the vehicle's electric
power train to ensure comprehensive electric shock protection.
    However, we acknowledge that the definition in the June 14, 2010
final rule may not sufficiently distinguish the components included by
the ``high voltage source'' definition from those that are not
included. To clarify our intent today's final rule defines a high
voltage source as ``any electric component contained in the electric
power train or conductively connected to the electric power train that
has a working voltage greater than 30 VAC or 60 VDC (emphasis added).''
    To further clarify this new definition, today's final rule adds a
definition for ``electric power train'' stating that it refers to ``an
assembly of electrically connected components which includes, but is
not limited to, electric energy storage/conversion systems and
propulsion systems.'' The definition of ``electrical energy storage/
conversion system'' is updated as described above. Further, today's
final rule makes minor revisions to the definition of ``propulsion
system'' to mean ``an assembly of electric or electro-mechanical
components or circuits that propel the vehicle using the energy that is
supplied by a high voltage source. This includes, but is not limited
to, electric motors, inverters/converters, electronic controllers, and
associated wire harnesses and connectors, and coupling systems for
charging rechargeable energy storage systems.''
    These definitions adopt similar language from the Definitions and
the General sections of the ELSA document in order to both address the
Alliance, AIAM and Honda's suggestion that the agency adopt the ELSA
definitions where appropriate and to more clearly define the components
that are included under the definition of ``high voltage source.''

c. Electric Energy Storage/Conversion System Retention

    In the NPRM, NHTSA proposed adjusting the ``Battery retention''
requirements of paragraph S5.2 to properly reflect the additional
energy storage devices that the updated standard intended to cover. The
adjustment to paragraph S5.2 accomplished this goal by proposing to
replace the word ``battery'' with the words ``energy storage device''
in S5.2 and adjust other portions of the regulatory text accordingly.
    In the final rule, we amended the regulatory text based on the
considerations in the NPRM and in response to additional information
from a March 9, 2009 interpretation request from Hyundai. Hyundai
stated that the requirements of S5.2 allowed a battery module located
outside the passenger compartment to become dislodged as long as it
does not enter the occupant compartment, while a module that is located
within the occupant compartment must simply remain in the location in
which it is installed. Hyundai stated that this may not properly
address the intent of the standard in some circumstances.\6\ It argued
that in vehicles such as sport utility vehicles (SUV) or station
wagons, a battery module located inside the occupant compartment that
moves during impact due to the deformation of the floor but remains
firmly attached to its mounting, would technically fail the retention
requirement even though it would not pose a projectile hazard.
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    \6\ 65 FR 57985, FMVSS No. 305 Final Rule, September 27, 2000.
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    The agency elected to respond to Hyundai's interpretation request
in the June 14, 2010 final rule because the NPRM in this rulemaking had
already proposed to amend the language of S5.2. Thus, in the final
rule, the agency responded to that interpretation request stating

    ``The agency agrees that battery modules located inside the
occupant compartment technically may move a small amount from the
location from which they are installed during the impact tests. The
agency also agrees that battery modules located outside the occupant
compartment that partially move into the occupant compartment
because of structural deformation of the vehicle structure do not
impose a projectile hazard provided that they remain attached to the
mounting structure.\7\ Therefore, the agency concurs that battery
modules located outside the occupant compartment should be treated
in the same manner as those located inside the occupant compartment,
provided that they remain attached to their anchorages.''
---------------------------------------------------------------------------

    \7\ 75 FR 33523.

    Accordingly, the June 14, 2010 final rule revised the regulatory
---------------------------------------------------------------------------
text to read as follows:

    S5.2 Electric energy storage/conversion system retention. All
components of the electric energy storage/conversion system must be
anchored to the vehicle. All component anchorages, including any
brackets or structures that transfer loads from the component to the
vehicle structure, shall remain attached to the vehicle structure at
all attachment locations during and after testing performed pursuant
to the procedures of S6 of this standard.

    In its petition for reconsideration of the June 14, 2010 final
rule, the Alliance stated that the final rule's specification that all
component anchorages, shall remain attached to the vehicle structure at
all attachment locations is an overly broad requirement that goes
beyond the intent of assuring that battery system components do not
become separated from the vehicle. The Alliance stated that this
language could be interpreted as prohibiting a plastic tie-wrap used to
position a wiring harness to the vehicle from severing in a crash, a
requirement that is neither practicable nor necessary.
    The Alliance and the AIAM further stated that some electric energy
storage/conversion systems, especially those which are located in the
engine compartment are protected from serious damage resulting from the
collision by absorbing the energy into deforming or even breaking
component mountings. The Alliance stated that this was analogous to
other energy management strategies, such as allowing steering

columns mountings to deform and break to keep the steering column away
from the driver of a vehicle during a severe crash. The Alliance stated
that a battery pack could be mounted to the vehicle at a dozen
attachment points, and the fact that one of these attachments severs
during a crash test would be inconsequential to the secure attachment
of the battery pack to the vehicle, yet violate the language of the
final rule. The AIAM stated that these system retention provisions may,
in some respects, be unnecessarily design restrictive and potentially
contrary to the interests of safety because rather than broadly
mandating that the battery remain attached to the vehicle, the
regulatory text places undue emphasis on the condition of individual
anchorages, brackets and structures.
    Both the AIAM and Honda further argued that the intent of S5.2 was
to ensure that the battery modules would not become unattached and
become flying projectiles in a crash or subsequent rollover. Each
referenced the September 27, 2000 final rule establishing FMVSS No. 305
\8\ where the agency stated, ``We note that the intent of the proposed
requirements in S5.2 was to ensure that the battery modules would not
become unattached and become flying projectiles in a crash or
subsequent rollover.'' The AIAM stated that this regulatory goal is
best served by a requirement that broadly focuses on the overall
condition of the battery module (whether it remains attached to the
vehicle and has not intruded into the passenger compartment) rather
than the condition of the individual anchorages.
---------------------------------------------------------------------------

    \8\ 65 FR 57985.
---------------------------------------------------------------------------

    Finally, the AIAM and Honda also stated that there are many smaller
components that paragraph S5.2 in the June 14, 2010 final rule applies
to, such as ducts or vents, which may become unattached. They argued
that the occupant injury risk from such components of the energy
storage/conversion system is very low, given their small mass and that
there are no comparable requirements for internal combustion engine
(ICE) vehicles. The AIAM and Honda stated that in order to exclude low
mass components of the energy storage/conversion system, such as ducts
and vents, the retention requirements should apply only to energy
storage/conversion devices rather than to energy storage/conversion
systems.
    Each of the petitioners had different strategies for amending the
requirements for electric energy storage/conversion system retention.
The Alliance petitioned that in order to avoid unnecessary design
limitations while achieving protection from both physical damage and
electrical shock, the following language be adopted for S5.2 of FMVSS
No. 305:

    ``The following requirements shall be met during and after
testing performed pursuant to the procedures of S6 of this standard:
    1. Energy storage/conversion system components shall remain
secured to the vehicle, and
    2. For energy storage/conversion system components located
outside the passenger compartment, such components shall not enter
the passenger compartment airspace.''

The Alliance also requested that if the agency does not agree with the
proposed language, the agency revert to the previous language of S5.2.
    The AIAM petitioned the agency to amend S5.2 to read as follows:

    ``S5.2 Electric energy storage/conversion device(s) retention.
Electric energy storage/conversion devices must remain attached to
the vehicle during and after testing performed pursuant to the
procedures of S6 of this standard.''

    Honda petitioned to amend S5.2 as follows:

    ``S5.2 Electric energy storage/conversion devices(s) retention.
The electric energy storage/conversion device(s) must remain
attached to the vehicle by anchorages, brackets, or structures that
transfer loads from the device(s) to the vehicle structure during
and after testing performed pursuant to the procedures of S6 of this
standard.''

    NHTSA's Response: We agree with the comments from the Alliance,
AIAM, and Honda suggesting that the changes to the retention
requirement in the June 14, 2010 final rule may be overly broad. We
acknowledge that increased crash protection for energy storage/
conversion systems can be achieved through the deformation or breaking
of certain component mounting/anchorages to absorb the crash energy. We
further acknowledge that the language in the June 14, 2010 final rule
can be construed to include plastic tie-wraps used to position a wiring
harness which are not consequential towards the overall condition of
the energy storage/conversion systems.
    However, we decline to adopt the regulatory text proposed by
petitioners because we are concerned with ensuring that the final
standard is clear and objective. Thus, the agency does not believe that
the proposed language changes from the AIAM and the Alliance are
appropriate as they require that the electric energy storage/conversion
devices remain attached without offering any specifics on how the
agency would distinguish between a device that has ``remained
attached'' and one that has not. The regulatory text proposed by Honda
offers more information on what constitutes ``remaining attached'' by
indicating that the electric energy storage/conversion device must
remain attached via ``anchorages, brackets, or structures that transfer
loads from the device(s) to the vehicle.'' However, this approach
remains unclear as it does not specify how many anchorages, brackets,
or structures that transfer load must remain attached.
    Thus, today's final rule addresses the considerations of ensuring
adequate crash protection, creating an objective standard, and enabling
industry designs that utilize anchorages to redirect crash forces by
establishing regulatory text which requires that the electric energy
storage/conversion devices remain attached to the vehicle by at least
one component anchorage, bracket, or any structure that transfer loads
from the component to the vehicle structure. Using this regulatory
text, the agency can afford the manufacturers the maximum amount of
flexibility to utilize the anchorages as a method for redirecting crash
forces in their vehicle designs while still ensuring that electric
energy storage/conversion devices do not become projectiles which can
potentially injure vehicle occupants. Further, the additional
regulatory text adds clarity and objectivity to the standard by
specifying how the agency will distinguish between devices that have
remained attached versus those that have not. Namely, the additional
text clarifies that this standard only requires that the electric
energy storage/conversion devices maintain a connection to the vehicle
structure at one or more load transferring point after it is tested in
accordance with the test procedures in S6.
    However, since we are not requiring all component anchorages to
remain attached to the vehicle at all attachment locations, we believe
that the June 14, 2010 final rule's conclusion that there is no need to
treat devices inside the occupant compartment differently from those
outside the occupant compartment is no longer accurate. While we agree
with petitioners that the intent of the retention requirement, as
specified in the 2000 final rule, was to ensure that battery modules
would not become unattached and become flying projectiles in a crash or
subsequent rollover, this is not the only purpose of the retention
requirement. One of the purposes of FMVSS No. 305 is to reduce deaths
and injuries during and after a crash that occur from the intrusion of
electric energy storage/conversion devices into the occupant
compartment.

In the June 14, 2010 final rule, the S5.2 requirement that all
component anchorages remain attached to the vehicle structure at all
attachment locations ensured that the energy storage/conversion system
would not significantly intrude into the occupant compartment.
    We recognize that, with the new regulatory text for S5.2 in today's
final rule, there may be an increased potential for electric energy
storage/conversion devices to partially detach from the vehicle
structure and intrude into the occupant compartment. To address this,
we are reintroducing the requirement that any electric energy storage/
conversion device located outside the occupant compartment not intrude
into the occupant compartment. However, we decline to use the term
``passenger compartment airspace'' as suggested by the Alliance. A
similar term ``occupant compartment air space'' was defined by the
agency in an interpretation letter \9\ of FMVSS No. 302, ``Flammability
of interior materials.'' Since FMVSS No. 305 addresses safety from
electrolyte spillage, electric shock, and intrusion of the energy
storage system, and does not address fire safety, the presence of
airspace is not relevant and we believe that ``occupant compartment''
is the more appropriate term for paragraph S5.2.
---------------------------------------------------------------------------

    \9\ Interpretation to Mazda (North America) Inc.--H. Nayaka:
February 15, 1983. An ``occupant compartment air space'' is defined
as ``the space within the occupant compartment that normally
contains refreshable air.''
---------------------------------------------------------------------------

    We also agree with Honda and the AIAM that the language of the June
14, 2010 final rule could be interpreted as unintentionally requiring
low mass components, such as ducts and vents, to remain attached to the
electric energy storage/conversion systems. As previously discussed,
today's final rule adds a new definition for ``electric energy storage/
conversion device,'' which includes a high voltage battery or battery
pack, capacitor modules, fuel cell stacks, and rechargeable energy
storage devices used for vehicle propulsion, but does not include low
mass components, such as ducts, vents, and wiring harnesses. As the
retention requirements of the final rule are amended in today's final
rule to apply to the electric energy storage/conversion device rather
than to the system, these changes address the concerns raised by the
AIAM and Honda by ensuring that the retention requirements do not apply
to low mass components.
    In conclusion, the regulatory text in paragraph S5.2 has been
amended to read as follows:
    S5.2 Electric energy storage/conversion device retention. During
and after each test specified in S6 of this standard:
    (a) electric energy storage/conversion devices shall remain
attached to the vehicle by at least one component anchorage,
bracket, or any structure that transfers loads from the device to
the vehicle structure, and
    (b) electric energy storage/conversion devices located outside
the occupant compartment shall not enter the occupant compartment.

d. Electrical Safety

1. Clarifying the Requirements in Paragraph S5.3
    Paragraph S5.3 of the June 14, 2010 final rule requires that each
high voltage source in a vehicle must meet the electrical isolation
requirements of subparagraph (a) or the voltage level requirements of
subparagraph (b) after each test. The subsections state:

    (a) The electric isolation between each high voltage source and
the vehicle chassis electricity-conducting structure must meet one
of the following:
    (1) Electrical isolation must be greater than or equal to 500
ohms/volt for all DC high voltage sources without continuous
monitoring of electrical isolation during vehicle operation and for
all AC high voltage sources; or
    (2) Electrical isolation must be greater than or equal to 100
ohms/volt for all DC high voltage sources with continuous monitoring
of electrical isolation, in accordance with the requirements of
S5.4, during vehicle operation.
    (b) The voltage of the voltage source must be less than or equal
to 30 VAC for AC components or 60 VDC for DC components.

    The Alliance stated that it believes that the agency has
inadvertently written the electrical safety requirements in the final
rule in a way that would permit compliance with S5.3(a)(2) as the sole
basis for complying with S5.3 in total. It noted that S5.3 states that
the vehicle must meet the electrical isolation requirements of
subparagraph (a) or the voltage requirements of subparagraph (b). It
further noted that if subparagraph (a) is chosen, the language permits
compliance to either subparagraph (1) or subparagraph (2), and if
subparagraph (2) is chosen, there are no isolation requirements
specified for AC high voltage sources. The Alliance requested
clarification on whether the agency intended to require 500 ohms/volt
isolation for AC sources in subparagraph (a) in both the subsidiary
options of subparagraph (a).
    NHTSA's Response: NHTSA agrees with the Alliance that the
regulatory text in S5.3(a) could be interpreted to imply that for a
vehicle with continuous monitoring of electrical isolation, only the DC
high voltage components need to meet the 100 ohms/volt electrical
isolation and that there are no requirements for AC high voltage
components. This was clearly not the intent. We are amending the
regulatory text of S5.3(a) to indicate that the electrical isolation
between a given high voltage source and any electrical chassis of the
vehicle must be greater or equal to one of the following: (1) 500 ohms/
volt for an AC high voltage source, or (2) 500 ohms/volt for a DC high
voltage source without electrical isolation monitoring, or (3) 100
ohms/volt for a DC high voltage source with electrical isolation
monitoring during vehicle operation. In order to further clarify
paragraph S5.3, we have included references to specific portions of the
test procedures that apply to the electrical safety requirements. In
addition, the term ``vehicle chassis electricity conducting structure''
in S5.3 has been replaced by the term ``electrical chassis'' to
maintain consistency with the changes discussed earlier in this
document. In conclusion, today's final rule amends paragraph S5.3 as
follows:

    S5.3 Electrical safety. After each test specified in S6 of this
standard, each high voltage source in a vehicle must meet the
electrical isolation requirements of subparagraph (a) or the voltage
level requirements of subparagraph (b).
    (a) The electrical isolation of the high voltage source,
determined in accordance with the procedure specified in S7.6, must
be greater or equal to one of the following:
    (1) 500 ohms/volt for an AC high voltage source; or
    (2) 500 ohms/volt for a DC high voltage source without
electrical isolation monitoring during vehicle operation; or
    (3) 100 ohms/volt for a DC high voltage source with electrical
isolation monitoring, in accordance with the requirements of S5.4,
during vehicle operation.
    (b) The voltages V1, V2, and Vb of the high voltage source,
measured according to the procedure specified in S7.7, must be less
than or equal to 30 VAC for AC components or 60 VDC for DC
components.

2. Testing Procedures for S5.3(b) Low Voltage Option
    The Alliance also stated in its petition that S5.3(b) of the final
rule adopted a low-voltage option for providing electrical isolation,
while S7.7 specifies the procedure for measuring the voltage. The
Alliance petitioned that, for purposes of clarity, the language
currently specified in S7.6.1 regarding voltage measurement locations
for the electrical isolation option be added to S7.7 for the low-
voltage option.
    NHTSA's Response: The agency agrees with the Alliance that the
procedure to measure the voltage in S7.6.1 should be added to S7.7 for
the

purposes of improving clarity. However, we believe S7.6.1 needs to be
modified to utilize the new definitions adopted above and to clarify
the measurement procedure before its contents are added to S7.7. The
test procedures in paragraph S7.6.1 of the June 14, 2010 final rule
states:

    For a vehicle that utilizes an automatic disconnect between the
high voltage source and the traction system that is physically
contained within the high voltage electric energy storage/
conversion/power generating system, the electrical isolation
measurement after the test is made from the traction-system side of
the automatic disconnect to the vehicle chassis electricity-
conducting structure. For a vehicle that utilizes an automatic
disconnect that is not physically contained within the high voltage
electric energy storage/conversion/power generating system, the
electrical isolation measurement after the test is made from both
the high voltage source side and from the traction-system side of
the automatic disconnect to the vehicle chassis electricity-
conducting structure.

    As previously discussed, today's final rule has adopted new
definitions for ``electric power train'' and ``electrical chassis.''
Therefore, all instances of the term ``traction-system'' in S7.6.1 are
replaced by the term ``electric power train'' and all instances of the
term ``vehicle chassis electricity-conducting structure,'' are replaced
by the term ``electrical chassis.'' This final rule also amends the
definition for ``high voltage source'' to include electric components
contained in the electric power train and those connected to it. For
high voltage sources contained within the electric power train, the
regulatory text of S7.6.1 and S7.7 have been amended to indicate that
the electrical isolation measurement is made from the side of the
automatic disconnect that is connected to ``the rest of the electric
powertrain.'' In addition, the regulatory text of the June 14, 2010
final rule S7.6.1 indicates that the ``automatic disconnect'' only
applies to high voltage sources within the vehicle's energy storage/
conversion/power generating system. We believe that this regulatory
text may be misconstrued, since the intent of the agency was that the
specifications for the electrical isolation measurement locations with
respect to the automatic disconnects in S7.6.1 apply to each high
voltage source with automatic disconnects. Therefore, the regulatory
text of S7.6.1 in today's final rule is modified as follows and
incorporated into S7.7 as requested by the Alliance:

    For a high voltage source that has an automatic disconnect that
is physically contained within itself, the electrical isolation
measurement after the test is made from the side of the automatic
disconnect connected to the electric power train or to the rest of
the electric power train if the high voltage source is a component
contained in the power train. For a high voltage source that has an
automatic disconnect that is not physically contained within itself,
the electrical isolation measurement after the test is made from
both the high voltage source side of the automatic disconnect and
from the side of the automatic disconnect connected to the electric
power train or to the rest of the electric power train if the high
voltage source is a component contained in the power train.

    However, to ensure consistency and clarity of terminology, today's
final rule also revises the first sentence in S7.6.1 to indicate that
the electric energy storage/conversion system (rather than the high
voltage source) is connected to the vehicle's propulsion system to
enable the propulsion system to be energized when the vehicle ignition
is in the ``on'' position. A similar clarification is made in S7.2 by
replacing ``high voltage system'' (which is not defined in the
regulatory text) with ``electric energy storage/conversion system'' and
``propulsion motors'' with ``propulsion system.''

e. Electrical Isolation Monitoring

    While the NPRM did not propose a requirement for electrical
isolation monitoring, we acknowledged in the NPRM that the petitioner
for rulemaking requested that FMVSS No. 305 allow for DC high voltage
sources to meet a 100 ohms/volt electrical isolation requirement when
coupled with electrical isolation monitoring. In the final rule, based
on our analysis of comments on the NPRM, we required that each DC high
voltage source meet 500 ohms/volt electrical isolation for vehicles
without continuous electrical isolation monitoring but allowed DC high
voltage sources to meet 100 ohms/volt electrical isolation if the
vehicle had continuous monitoring of electrical isolation during
vehicle operation. We required that the system must monitor its own
readiness and provide a warning display that must be clearly visible
from the driver's designated seating position for loss of isolation
when tested according to the test procedure in S8.
    The agency stated its belief that electrical isolation monitoring
is especially needed for electrical components whose electrical
isolation may degrade over time such as fuel cell stacks in fuel cell
vehicles where the coolant may increase in conductivity during vehicle
service and thereby result in a reduction of electrical isolation.
Since it is anticipated that the 100 ohms/volt electrical isolation
requirement for DC high voltage components would likely be exercised
for the fuel cell stacks and other such electrical components whose
isolation may degrade over time, we included the need for isolation
monitoring of these components in the final rule.
    In its petitions for reconsideration, Honda stated that the level
of protection against electric shock should be judged by the absolute
value of electrical isolation resistance. Honda argued that whether or
not the vehicle is equipped with an isolation monitor has no relation
to the possibility of electric shock resulting from touching the high
voltage bus after a crash. Honda proposed removing entire sections of
S5.4 and S8 related to isolation monitoring systems. Honda noted that
the 2009 SAE J2578 \10\ and the 2009 ISO 6469-3 \11\ draft standards do
not require electrical isolation monitoring for electrical components
with 100 ohms/volt electrical isolation and requested that the
electrical isolation monitoring requirements be removed to resolve the
differences between the FMVSS No. 305 and the SAE/ISO standards.
---------------------------------------------------------------------------

    \10\ SAE J2578--Recommended practice for general fuel cell
vehicle safety, SAE J2578-2009-01, Society of Automotive Engineers,
http://standards.sae.org/j2578_200901/.
    \11\ ISO 6469-3--Electrically propelled road vehicles--Safety
specification--Part 3: Protection of persons against electric shock,
2009, http://www.iso.org/iso/catalogue_detail?csnumber=45479.
---------------------------------------------------------------------------

    Honda requested that if NHTSA decides not to remove the electrical
isolation monitoring requirement, it instead permit periodic electrical
isolation monitoring systems such as those that do not monitor the
electrical isolation during start-up of vehicle/system (until main
contactor is connected). Honda stated that the 2010 draft of ISO 6469-3
and the 2006 draft of ISO 23273-3 permit both continuous and periodic
electrical isolation measurements during vehicle operation and that
``periodic'' systems would also detect a failure in isolation and
appropriately warn the driver. Therefore, Honda proposed FMVSS No. 305
include the words ``or periodic'' after the word, ``continuous'' in
S5.3, S5.4 and S8.
    Further, Honda stated that the electrical isolation monitoring
system only monitors the entire system during normal vehicle operation
and is not capable of independently monitoring each high voltage
source. Therefore, Honda requested that the agency clarify that the
electrical isolation monitoring system will not be required to
independently monitor each high voltage source by deleting the words
``For each continuously monitored DC

high voltage source,'' from the regulatory text in S5.4.
    Finally, Honda stated that the test procedure to determine the
operation of isolation monitoring systems does not allow flexibility in
selecting the resistor that is inserted between the positive terminal
of the high voltage source and the vehicle chassis electric conducting
structure. Honda noted that, as prescribed, S8(4) requires inserting a
resistor with resistance equal to the calculated result 1/(1/(95 times
the working voltage of the high voltage source)--1/Ri) and does not
allow any flexibility. Honda petitioned to allow any higher resistor to
be used in the test procedure to determine if the isolation monitoring
system is operating correctly arguing that the stringency of the test
would not be compromised since higher resistance would provide a worse
case condition.
    NHTSA's Response--While we agree with Honda that isolation
monitoring is intended to identify the possibility of deteriorated
isolation that occurs over time during the normal service life of the
vehicle and that an isolation monitor is not intended to guard against
the possibility of electric shock resulting from touching a high
voltage source after a crash, we do not agree that the requirement for
electrical isolation monitoring should be deleted from the standard.
The requirement that DC high voltage sources be monitored during
vehicle operation with an isolation monitoring system that displays a
warning for loss of electrical isolation is similar to the air bag
readiness indicator required by FMVSS No. 208, ``Occupant crash
protection.'' Neither the electrical isolation warning display nor the
air bag readiness indicator provides protection during or after a
crash. However, these indicators serve to provide the driver
information that the related system may not be in proper working
condition. Electrical isolation monitoring addresses a relevant safety
concern because electric vehicles that use the 100 ohms/volt electrical
isolation option to comply with the electrical safety requirements may
likely be powered by fuel cells which have coolant that can deteriorate
the electrical isolation over time. The agency made the decision to
require electrical isolation monitoring based on careful analysis of
the electrical safety concerns associated with providing adequate
electrical shock protection both during vehicle operation and following
a crash.
    We also note that the electrical isolation and the electrical
isolation monitoring requirements in the June 14, 2010 final rule were
consistent with the joint Alliance/AIAM comments to the NPRM and SAE
J1766. The standards referred to by Honda in its petition (SAE J2578
and ISO 6469-3) are draft documents that may be subject to change. For
example, the 2009 draft of ISO 6469-3 does not require electrical
isolation monitoring while the 2010 version makes provisions for
continuous and periodic electrical isolation monitoring. As the
aforementioned voluntary standards are still in flux regarding
requiring electrical isolation monitoring, and as the agency believes
that electrical isolation monitoring addresses an important safety
concern by warning the driver of a possible degradation in electrical
isolation, we are denying Honda's petition to remove the electrical
isolation monitoring requirements from S5.4 and S8.
    However, we agree with Honda's petition that the term
``continuous'' in the electrical isolation monitoring system
requirement should be clarified. Since the standard provides a test
procedure and performance criteria for assessing the operation of the
electrical isolation monitoring system, we believe there is no need to
specify the type of monitoring system. The only requirement contained
in today's final rule is that the monitoring systems meet the
performance criteria in S5.4 when tested according to the procedure in
S8. Therefore, rather than adding the additional term ``or periodic,''
as suggested by Honda, we are deleting the specification for the
monitoring system to be ``continuous'' in S5.3, S5.4, and S8 to address
its concern. We are also modifying the regulatory text of S5.4 slightly
to improve clarity.
    We agree with Honda that electrical isolation monitoring systems
may only monitor the whole vehicle system. However, the regulatory
requirements in S5.4 only apply to those DC high voltage sources that
manufacturers have chosen to certify to the 100 ohms/volt electrical
isolation requirement and do not comply with the 500 ohms/volt
electrical isolation requirement. Therefore, the test procedure in S8
evaluates the performance of the monitoring system for each DC high
voltage source that is certified to 100 ohms/volt electrical isolation.
The procedures in S8 are intended to test for the condition when
electrical isolation of each DC high voltage source (certified to the
100 ohms/volt requirement) falls below 100 ohms/volt. Therefore, we do
not grant Honda's request to remove the phrase ``For each continuously
monitored DC high voltage source'' from the regulatory text in S5.4.
    Finally, Honda also petitioned for flexibility in the use of any
higher resistor in the test procedure to determine if the isolation
monitoring system is operating correctly. It argued that allowing a
higher resistance would not compromise the stringency of the
requirements since it would provide for a worse case condition. In the
June 14, 2010 final rule, the resistance of the external resistor
applied in the test procedure detailed in S8 is calculated such that
the combined electrical isolation resistance of the high voltage source
and the external resistor results in electrical isolation of 95 ohms/
volt which is 95 percent of the required electrical isolation. The
electrical isolation monitor is required to display a warning when the
electrical isolation falls to 95 ohms/volt. If the resistance of the
external resistor applied in the test is greater than that specified in
S8, as requested by Honda, then we agree that the combined electrical
isolation for which the monitoring system will need to display a
warning may be greater than 100 ohms/volt, thereby making the
requirement more stringent.
    The final rule requires 100 ohms/volt electrical isolation for
monitored DC high voltage sources. For compliance purposes, we are
assessing the operation of the monitoring system when the electrical
isolation falls just below the required value. The final rule does not
preclude manufacturers from having the isolation monitor warning
display come on at a higher value than the minimum electrical isolation
of 100 ohms/volt. Therefore, we do not believe it is necessary to grant
Honda's request to change S8(4) to include an external resistor of
higher resistance than that specified by the calculation.
    However, we do see merit in including some flexibility in the
resistance of the external resistor selected to evaluate the electrical
isolation monitoring system such that it is easy for the testing
personnel to select an off-the-shelf resistor instead of having to
build a resistor to meet the exact computed resistance of the external
resistor. Therefore, we are specifying that the resistance of the
external resistor be such that the combined electrical isolation is
greater or equal to 95 ohms/volt but less than 100 ohms/volt. This will
allow the agency to test the operation of the monitoring system when
the electrical isolation falls just below the required 100 ohms/volt,
and will provide manufacturers additional flexibility in selecting
resistors for testing.

f. Electric Energy Storage Device State-of-Charge

    In the June 14, 2010 final rule, we required that prior to the
crash test, the electric energy storage device be at the

maximum state-of-charge recommended by the manufacturer, as stated in
the vehicle owner's manual or on a label that is permanently affixed to
the vehicle; or if the manufacturer has made no recommendation in the
owner's manual or on a label permanently affixed to the vehicle, at a
state-of-charge of not less than 95 percent of the maximum capacity of
the electric energy storage device; or if the electric energy storage
device(s) is/are rechargeable only by an energy source on the vehicle,
at any state-of-charge within the normal operating voltage defined by
the vehicle manufacturer. These state-of-charge provisions in the June
14, 2010 final rule were substantively identical to the original FMVSS
No. 305 that existed before the NPRM in this rulemaking.
    In its petition asking the agency to reconsider these provisions,
the Alliance requested that FMVSS No. 305 be amended to allow testing
at ``any state-of-charge which allows the normal operation of the power
train as recommended by the manufacturer.'' In support of this request,
the Alliance stated that the United Nations Economic Commission for
Europe (UNECE) draft regulations (ECE R.94 and 95) \12\ already propose
to permit testing of electric vehicles at any state-of-charge. The
Alliance stated that this proposed change would (1) allow for systems
with external charging capability to be tested at lower state-of-charge
(similar to hybrid electric vehicles), (2) result in reduced facility/
test personnel risk (similar to the current use of stoddard in fuel
systems), and (3) further provide an opportunity for harmonization with
UNECE regulations. Thus, the Alliance argued that in the interest of
safety in the testing environment and harmonization, the UNECE
allowance on state-of-charge should be adopted.
---------------------------------------------------------------------------

    \12\ ECE R.94--Uniform Provisions Concerning the Approval of
Vehicles with Regard to the Protection of the Occupants in the Event
of a Frontal Collision, draft modifications of September 2010. ECE
R.95--Uniform Provisions Concerning the Approval of Vehicles with
Regard to the Protection of the Occupants in the Event of a Lateral
Collision, draft modifications of September 2010.
---------------------------------------------------------------------------

    Ford also offered comments regarding the state-of-charge and the
FMVSS No. 305 test conditions. Ford stated that state-of-charge does
not affect the energy storage/conversion system mass, electrolyte
volume or containment capability and does not affect electrical
isolation. Ford presented theoretical examples of systems suffering
loss of electrical isolation during the crash test prescribed in the
standard. Using the electrical isolation test procedure outlined in the
standard, Ford demonstrated that the loss in electrical isolation was
detected when the system was energized at 95 percent and 5 percent of
the maximum state-of-charge. Ford agreed with the Alliance that the
lower state-of-charge would reduce potential risk to test personnel
similar to the use of substitute liquids and gases in other FMVSSs.
    In addition, Honda's petition stated that the state-of-charge
testing requirements should be amended to address new technologies such
as plug in hybrid electric vehicles (PHEVs) which will become common in
the near future. Honda noted that the regulatory text indicates that if
the manufacturer of vehicles (such as PHEVs) recommends a specific
maximum state-of-charge, the test would be conducted at the specified
maximum state-of-charge. However, if the manufacturer has no
recommendation, the test would be conducted at a state-of-charge of not
less than 95 percent of the maximum capacity of the electric energy
storage device.
    Honda argued that the state-of-charge for an electric energy
storage device can vary due to environmental conditions such as
temperature or service life and that it will not be recommending a
specific state-of-charge in the owner's manual or on the label affixed
to the vehicle because the electric energy storage device is charged
appropriately by an off-board and/or on-board charger recommended by
the manufacturer. Thus, Honda petitioned to have the regulatory text of
S7.1 changed from ``recommended by the manufacturer, as stated in the
vehicle owner's manual or on a label that is permanently affixed to the
vehicle'' to ``in accordance with the vehicle manufacturer's
recommended charging procedures.'' For those manufacturers that make no
recommendation, Honda further petitioned to have the regulatory text of
S7.1(b) changed from ``made no recommendation in the owner's manual or
on a label permanently affixed to the vehicle'' to ``made no
recommendation for charging procedures.''
    NHTSA's Response: NHTSA does not agree with the Alliance and Ford
that the electric energy storage device should be at any state-of-
charge that allows for the normal operation of the power train as
recommended by the manufacturer. Specifying the state-of-charge
provides a uniform way of testing and ensures all electric powered
motor vehicles are tested in a similar manner.
    We agree with Ford that the electrical isolation resistance
measurement remains unchanged for different operating voltages and that
loss in electrical isolation can be detected by the method outlined in
the standard for different states of charge. However, we are concerned
that certain electric components, such as capacitor networks within the
electric power train may not be tested to their design limits when
tested at a lower state-of-charge. When the vehicle crash test is
conducted at the maximum state-of-charge, there is potential for some
of the capacitor voltages to reach their design limits which may result
in an electric short and hence cause a loss in electrical isolation.
This potential safety hazard may not occur when the vehicle is tested
at a lower state-of-charge which results in a lower energy test
condition. We also do not agree with petitioners that testing at lower
state-of-charge to evaluate electrical safety is similar to fuel system
integrity testing with stoddard fluid in gasoline powered vehicles and
nitrogen in compressed natural gas vehicles. While use of stoddard
fluids and nitrogen do not change the performance of the fuel
containers during and after the test, using lower state-of-charge may
not evaluate certain electrical components at their design limits.
    We further note that the December 2010 draft of SAE J2929--
``Electric and Hybrid Vehicle Propulsion Battery System Safety Standard
for Lithium-Based Rechargeable Cells,'' requires the battery state-of-
charge to be at the maximum possible during normal vehicle operation
before the battery system is tested for mechanical shock hazard in a
vehicle pursuant to FMVSS No. 305. While the draft SAE J2929 test
applies to different safety concerns, it does involve the same crash
tests as this standard and utilizes similar state-of-charge
requirements. Therefore, the agency's position on the state-of-charge
of the energy storage/conversion system prior to the crash test is
consistent with the future voluntary industry standard for battery
systems. We are therefore denying the petition from the Alliance and
Ford to conduct the crash test at any state-of-charge which allows the
normal operation of the power train as recommended by the manufacturer.
    However, we agree with Honda that the maximum state-of-charge may
vary based on environmental conditions such as the age of the battery,
temperature and service life for today's battery technologies. Thus,
having the label specify the maximum state-of-charge in the owner's
manual or a label permanently affixed to the vehicle may not provide
consumers the information they need to recharge their vehicle
throughout the vehicle's life. However, manufacturers will likely
provide information to consumers on the proper charging procedures to
achieve

maximum range, as suggested by Honda. Therefore, we are modifying the
regulatory text to indicate that the maximum state-of-charge in
accordance with the vehicle manufacturer's recommended charging
procedure, as stated in the vehicle owner's manual or on a label that
is permanently affixed to the vehicle, will be used. In the case where
no such recommendation is provided in the owner's manual or on a label
permanently affixed to the vehicle, the test will be conducted with the
electric energy storage/conversion device charged to 95 percent of its
rated capacity.

 g. Physical Barrier Compliance Option for Electrical Safety

    The June 14, 2010 final rule did not include a physical barrier
compliance option for electrical safety since it was beyond the scope
of the rulemaking. In addition, the agency stated in the final rule
that it was uncertain whether indirect contact failure modes would be
sufficiently accounted for by the protective barrier compliance option
and noted that it had initiated a research program to better understand
the issues.
    In its petition for reconsideration, the Alliance disagreed with
the agency's concern that the physical barrier option may not
appropriately address electrical shock from indirect contact. The
Alliance stated its belief that the test procedure for the protective
barrier compliance option is equally valid for assessing both direct
and indirect contact. It stated that the basic premise of the
protective barrier compliance option is that if a person cannot contact
high voltage sources, then there is little chance of injury from such
sources.
    The Alliance further stated that there is worldwide recognition and
acceptance of the barrier option as a means for providing electrical
safety, and updating FMVSS No. 305, as requested, would be a key
enabler facilitating the introduction of all forms of electric-powered
vehicles into the U.S. mainstream vehicle fleet. It argued that such
vehicle technologies are vital to achieving the current
Administration's energy and emissions goals. The Alliance further
stated that given the urgent need for the barrier option and the fact
that the barrier option in the draft GTR language (the ELSA document)
is fully accepted by the international community, it is not necessary
to delay a rulemaking proposal. Accordingly, the Alliance requested
that NHTSA initiate a new rulemaking to incorporate the barrier option
into FMVSS No. 305, and to complete this rulemaking with an urgency
that is consistent with the national priorities to improve energy
independence and reduced emissions.
    NHTSA's Response: Our position on the requested physical barrier
option has not substantively changed since the June 14, 2010 final
rule. As noted in the June 14, 2010 final rule, NHTSA is doing research
to evaluate the suitability of including the protective barrier option
in FMVSS No. 305. NHTSA is aware that other countries have adopted a
similar option in their regulations for electrical safety, but that
does not eliminate the need for the agency to obtain the necessary
supporting research to fully understand the consequences of adding this
option as a means for providing electrical safety in FMVSS No. 305.
Prior to changing any safety standard, NHTSA must first ensure that the
proposed requirement provides an adequate level of safety and does not
create an inadvertent safety risk to the motoring public, or first
responders responding to the scene of a crash. Upon completion of the
agency's research, NHTSA will make a decision whether to include
physical barriers as an option for providing electrical safety in FMVSS
No. 305. If the agency decides that a proposal for the protective
barrier compliance option has merit, it will propose performance
requirements, as well as a test procedure, at that time.

h. Use of Alternative Gas for Testing Hydrogen Fuel Cell Vehicles

    The June 14, 2010 final rule also did not include a provision for
testing hydrogen fuel cell vehicles using an inert gas, such as helium.
When testing with an inert gas, the fuel cell stacks are not energized
and consequently will not generate any electrical energy from which to
measure electrical output. The final rule stated that the agency was
researching potential crash test procedures for testing fuel cell
vehicles, but would not address this issue as part of the June 14, 2010
final rule.
    Petitions for reconsideration from the AIAM and Honda requested the
agency to expedite this research so that a decision can be made in the
near future for testing hydrogen fuel cell vehicles with helium-filled
fuel containers. The organizations noted that fuel cell vehicles will
be required to comply with FMVSS No. 305 by September 1, 2011. They
argued that testing for those vehicles will then have to be conducted
using hydrogen gas in accordance with the current regulation, if no
changes are made. The AIAM and Honda further stated that other FMVSS
crash test procedures (i.e. FMVSS Nos. 208, ``Occupant crash
protection,'' 214, ``Side impact crash protection,'' 301, ``Fuel system
integrity,'' and 303, ``Fuel system integrity of compressed natural gas
vehicles'') require filling the fuel tank with alternative fuel to
ensure safety during and after the crash test and the use of gasoline,
diesel, and compressed natural gas in such tests is prohibited. The
organizations requested that the test procedure for FMVSS No. 305 be
aligned with the procedures of other existing crash-related
regulations. Both organizations further reiterated their original
comments to the NPRM that current Japanese regulations require the use
of helium gas in crash tests, and prohibit the use of hydrogen.
    NHTSA's Response--As noted in the June 14, 2010 final rule, the
agency has ongoing research in developing a test procedure for
evaluating the electrical safety of fuel cell vehicles with an inert
gas and inactive fuel cells and the agency's position has not
substantively changed since then. When an inert gas is used instead of
hydrogen in fuel cell vehicles, some of the electrical components of
the electric power train may be rendered inactive. Currently, the
agency has not developed a test procedure to test the electrical safety
of all high voltage sources accurately when an inert gas is used during
testing of fuel cell vehicles. We note that while the Japanese
regulation and the ELSA document permit the use of helium gas in crash
tests of hydrogen powered vehicles, both the Japanese regulation and
the ELSA document do not specify a test procedure to evaluate the
electrical safety of such vehicles when an inert gas is used in place
of hydrogen.
    Therefore, the agency believes further work is needed to resolve
the identified issues in testing hydrogen fuel cell vehicles. While
there are currently no explicit provisions for using an alternative gas
in lieu of hydrogen, comparable to the fuel system integrity standards
for gasoline or compressed natural gas powered vehicles, the test
procedures in an FMVSS are those that the agency will use to determine
compliance to the particular standard. Manufacturers are not prohibited
from using other test procedures for compliance certification and may
elect to conduct crash tests of hydrogen fuel cell vehicles with a less
volatile gas such as helium.

i. Low-Energy Compliance Option for Electrical Safety

    Although the NPRM sought comment on whether or not the requested
low-energy compliance option for electrical safety should be included,
it did not include this option in the proposed rule. After carefully
considering the

comments received, the agency did not include the low-energy compliance
option in the June 14, 2010 final rule as we remained unconvinced that
the option was necessary and that it would adequately address the
safety concerns of FMVSS No. 305. In its petition for reconsideration,
the Alliance stated its continued belief that the low-energy option has
merit and should be included in FMVSS No. 305. However, the Alliance
also recognized that more research may be required in order to fully
understand the safety implications of this option. Given the available
information on the low-energy compliance option for electrical safety
has not significantly changed, NHTSA's position on the low-energy
compliance option remains as expressed in the June 14, 2010 final rule.

V. Rulemaking Analyses and Notices

a. Executive Order 12866, Executive Order 13563, and DOT Regulatory
Policies and Procedures

    NHTSA has considered the impact of this rulemaking action under
Executive Order 12866, Executive Order 13563, and the Department of
Transportation's regulatory policies and procedures. This rulemaking
document was not reviewed by the Office of Management and Budget under
E.O. 12866, ``Regulatory Planning and Review.'' It is not considered to
be significant under E.O. 12866 or the Department's Regulatory Policies
and Procedures (44 FR 11034; February 26, 1979). NHTSA has determined
that the effects of this final rule are minor and that a regulatory
evaluation is not needed to support the subject rulemaking. Today's
final rule only makes slight changes to the regulatory text of the June
14, 2010 final rule to add clarification and does not impose
significant costs beyond those already required by the June 14, 2010
final rule.

b. Regulatory Flexibility Act

    Pursuant to the Regulatory Flexibility Act (5 U.S.C. 601 et seq.,
as amended by the Small Business Regulatory Enforcement Fairness Act
(SBREFA) of 1996), whenever an agency is required to publish a notice
of proposed rulemaking or final rule, it must prepare and make
available for public comment a regulatory flexibility analysis that
describes the effect of the rule on small entities (i.e., small
businesses, small organizations, and small governmental jurisdictions).
No regulatory flexibility analysis is required if the head of an agency
certifies the rule will not have a significant economic impact on a
substantial number of small entities. SBREFA amended the Regulatory
Flexibility Act to require Federal agencies to provide a statement of
the factual basis for certifying that a rule will not have a
significant economic impact on a substantial number of small entities.
    NHTSA has considered the effects of this final rule under the
Regulatory Flexibility Act. I certify that this final rule does not
have a significant economic impact on a substantial number of small
entities. Any small manufacturers that might be affected by this final
rule are already subject to the requirements of FMVSS No. 305. Further,
the agency believes the testing associated with the requirements added
by this final rule are not substantial and to some extent are already
being voluntarily borne by the manufacturers pursuant to SAE J1766, SAE
J2578, ECE regulations, and other voluntary industry standards.
Therefore, the impacts on any small businesses affected by this
rulemaking would not be substantial.

c. Executive Order 13132 (Federalism)

    NHTSA has examined today's final rule pursuant to Executive Order
13132 (64 FR 43255; Aug. 10, 1999) and concluded that no additional
consultation with States, local governments, or their representatives
is mandated beyond the rulemaking process. The agency has concluded
that the final rule does not have sufficient federalism implications to
warrant consultation with State and local officials or the preparation
of a federalism summary impact statement. The final rule does not have
``substantial direct effects on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government.'' Today's
final rule does not impose substantial additional requirements.
Instead, it clarifies the existing requirements from the June 14, 2010
final rule.
    NHTSA rules can have preemptive effect in two ways. First, the
National Traffic and Motor Vehicle Safety Act contains an express
preemption provision:

    When a motor vehicle safety standard is in effect under this
chapter, a State or a political subdivision of a State may prescribe
or continue in effect a standard applicable to the same aspect of
performance of a motor vehicle or motor vehicle equipment only if
the standard is identical to the standard prescribed under this
chapter.

49 U.S.C. 30103(b)(1). It is this statutory command that preempts any
non-identical State legislative and administrative law \13\ addressing
the same aspect of performance, not today's rulemaking.

    \13\ The issue of potential preemption of state tort law is
addressed in the immediately following paragraph discussing implied
preemption.
---------------------------------------------------------------------------

    The express preemption provision described above is subject to a
savings clause under which ``[c]ompliance with a motor vehicle safety
standard prescribed under this chapter does not exempt a person from
liability at common law.'' 49 U.S.C. 30103(e). Pursuant to this
provision, State common law tort causes of action against motor vehicle
manufacturers that might otherwise be preempted by the express
preemption provision are generally preserved. However, the Supreme
Court has recognized the possibility, in some instances, of implied
preemption of State common law tort causes of action by virtue of
NHTSA's rules--even if not expressly preempted.
    This second way that NHTSA rules can preempt is dependent upon the
existence of an actual conflict between an FMVSS and the higher
standard that would effectively be imposed on motor vehicle
manufacturers if someone obtained a State common law tort judgment
against the manufacturer--notwithstanding the manufacturer's compliance
with the NHTSA standard. Because most NHTSA standards established by an
FMVSS are minimum standards, a State common law tort cause of action
that seeks to impose a higher standard on motor vehicle manufacturers
will generally not be preempted. However, if and when such a conflict
does exist--for example, when the standard at issue is both a minimum
and a maximum standard--the State common law tort cause of action is
impliedly preempted. See Geier v. American Honda Motor Co., 529 U.S.
861 (2000).
    Pursuant to Executive Order 13132, NHTSA has considered whether
this rule could or should preempt State common law causes of action.
The agency's ability to announce its conclusion regarding the
preemptive effect of one of its rules reduces the likelihood that
preemption will be an issue in any subsequent tort litigation.
    To this end, the agency has examined the nature (e.g., the language
and structure of the regulatory text) and objectives of today's rule
and finds that this rule merely clarifies the requirements and
definitions contained in the June 14, 2010 final rule. As such, NHTSA
does not intend that this rule preempt state tort law that would
effectively impose a higher standard on

motor vehicle manufacturers than that established by today's rule.
Additionally, in the June 14, 2010 final rule, the agency did not
assert preemption. Establishment of a higher standard by means of State
tort law would not conflict with the exemption announced here. Without
any conflict, there could not be any implied preemption of a State
common law tort cause of action.

d. National Environmental Policy Act

    NHTSA has analyzed this rulemaking action for the purposes of the
National Environmental Policy Act. The agency has determined that
implementation of this action will not have any significant impact on
the quality of the human environment.

e. Executive Order 12988 (Civil Justice Reform)

    When promulgating a regulation, agencies are required under
Executive Order 12988 to make every reasonable effort to ensure that
the regulation, as appropriate: (1) Specifies in clear language the
preemptive effect; (2) specifies in clear language the effect on
existing Federal law or regulation, including all provisions repealed,
circumscribed, displaced, impaired, or modified; (3) provides a clear
legal standard for affected conduct rather than a general standard,
while promoting simplification and burden reduction; (4) specifies in
clear language the retroactive effect; (5) specifies whether
administrative proceedings are to be required before parties may file
suit in court; (6) explicitly or implicitly defines key terms; and (7)
addresses other important issues affecting clarity and general
draftsmanship of regulations.
    Pursuant to this Order, NHTSA notes as follows. The preemptive
effect of today's final rule is discussed above. NHTSA notes further
that there is no requirement that individuals submit a petition for
reconsideration or pursue other administrative proceeding before they
may file suit in court.

f. Privacy Act

    Please note that anyone is able to search the electronic form of
all comments received into any of our dockets by the name of the
individual submitting the comment (or signing the comment, if submitted
on behalf of an association, business, labor union, etc.). You may
review DOT's complete Privacy Act Statement in the Federal Register
published on April 11, 2000 (65 FR 19477-78), or online at http://www.dot.gov/privacy.html.

g. Paperwork Reduction Act

    Under the Paperwork Reduction Act of 1995 (PRA), a person is not
required to respond to a collection of information by a Federal agency
unless the collection displays a valid OMB control number. There are no
information collection requirements associated with this final rule.

h. National Technology Transfer and Advancement Act

    Under the National Technology Transfer and Advancement Act of 1995
(NTTAA) (Pub. L. 104-113), ``all Federal agencies and departments shall
use technical standards that are developed or adopted by voluntary
consensus standards bodies, using such technical standards as a means
to carry out policy objectives or activities determined by the agencies
and departments.'' Voluntary consensus standards are technical
standards (e.g., materials specifications, test methods, sampling
procedures, and business practices) that are developed or adopted by
voluntary consensus standards bodies, such as the Society of Automotive
Engineers (SAE). The NTTAA directs us to provide Congress, through OMB,
explanations when we decide not to use available and applicable
voluntary consensus standards. FMVSS No. 305 has historically drawn
largely from SAE J1766. Prior to this update, FMVSS No. 305 was based
on the April 2005 version of SAE J1766. However, today's final rule has
made certain amendments to the standard to reflect the development of
new voluntary consensus standards that have superseded SAE J1766. Thus,
today's final rule makes revisions to the June 14, 2010 final rule that
updated FMVSS No. 305.

i. Unfunded Mandates Reform Act

    The Unfunded Mandates Reform Act of 1995 requires agencies to
prepare a written assessment of the costs, benefits and other effects
of proposed or final rules that include a Federal mandate likely to
result in the expenditure by State, local or Tribal governments, in the
aggregate, or by the private sector, of more than $100 million annually
(adjusted for inflation with base year of 1995). Today's final rule,
which clarifies the June 14, 2010 final rule, will not result in
expenditures by State, local or Tribal governments, in the aggregate,
or by the private sector in excess of $100 million annually.

j. Plain Language

    Executive Order 12866 requires each agency to write all rules in
plain language. Application of the principles of plain language
includes consideration of the following questions:
     Have we organized the material to suit the public's needs?
     Are the requirements in the rule clearly stated?
     Does the rule contain technical language or jargon that
isn't clear?
     Would a different format (grouping and order of sections,
use of headings, paragraphing) make the rule easier to understand?
     Would more (but shorter) sections be better?
     Could we improve clarity by adding tables, lists, or
diagrams?
     What else could we do to make the rule easier to
understand?
    If you have any responses to these questions, please notify the
agency in writing.

k. Regulation Identifier Number (RIN)

    The Department of Transportation assigns a regulation identifier
number (RIN) to each regulatory action listed in the Unified Agenda of
Federal Regulations. The Regulatory Information Service Center
publishes the Unified Agenda in April and October of each year. You may
use the RIN contained in the heading at the beginning of this document
to find this action in the Unified Agenda.

VI. Regulatory Text

List of Subjects in 49 CFR part 571

    Imports, Motor vehicles, Motor vehicle safety.

    In consideration of the foregoing, NHTSA amends 49 CFR part 571 as
follows:

PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS

0
1. The authority citation for part 571 continues to read as follows:

    Authority:  49 U.S.C. 322, 30111, 30115, 30117, and 30166;
delegation of authority at 49 CFR 1.50.

0
2. Amend Sec.  571.305 by revising S1, S2, S3, S4, S5.2, S5.3, S5.4,
S7.1, S7.2, S7.6.1, S7.6.4, S7.6.5, S7.6.6, S7.6.7, S7.7, and S8 and
Figures 1 through 5 as follows:

Sec.  571.305  Standard No. 305; Electric-powered vehicles: Electrolyte
spillage and electrical shock protection.

    S1. Scope. This standard specifies requirements for limitation of
electrolyte spillage, retention of electric energy storage/conversion
devices, and protection from harmful electric shock during and after a
crash.
    S2. Purpose. The purpose of this standard is to reduce deaths and
injuries

during and after a crash that occurs because of electrolyte spillage
from electric energy storage devices, intrusion of electric energy
storage/conversion devices into the occupant compartment, and
electrical shock.
    S3. Application. This standard applies to passenger cars, and to
multipurpose passenger vehicles, trucks and buses with a GVWR of 4,536
kg or less, that use electrical propulsion components with working
voltages more than 60 volts direct current (VDC) or 30 volts
alternating current (VAC), and whose speed attainable over a distance
of 1.6 km on a paved level surface is more than 40 km/h.
    S4. Definitions.
    Automatic disconnect means a device that when triggered,
conductively separates a high voltage source from the electric power
train or the rest of the electric power train.
    Electric energy storage device means a high voltage source that
stores energy for vehicle propulsion. This includes, but is not limited
to, a high voltage battery or battery pack, rechargeable energy storage
device, and capacitor module.
    Electric energy storage/conversion device means a high voltage
source that stores or converts energy for vehicle propulsion. This
includes, but is not limited to, a high voltage battery or battery
pack, fuel cell stack, rechargeable energy storage device, and
capacitor module.
    Electric energy storage/conversion system means an assembly of
electrical components that stores or converts electrical energy for
vehicle propulsion. This includes, but is not limited to, high voltage
batteries or battery packs, fuel cell stacks, rechargeable energy
storage systems, capacitor modules, inverters, interconnects, and
venting systems.
    Electric power train means an assembly of electrically connected
components which includes, but is not limited to, electric energy
storage/conversion systems and propulsion systems.
    Electrical chassis means conductive parts of the vehicle whose
electrical potential is taken as reference and which are: (1)
conductively linked together, and (2) not high voltage sources during
normal vehicle operation.
    Electrical isolation of a high voltage source in the vehicle means
the electrical resistance between the high voltage source and any of
the vehicle's electrical chassis divided by the working voltage of the
high voltage source.
    High voltage source means any electric component contained in the
electric power train or conductively connected to the electric power
train that has a working voltage greater than 30 VAC or 60 VDC.
    Propulsion system means an assembly of electric or electro-
mechanical components or circuits that propel the vehicle using the
energy that is supplied by a high voltage source. This includes, but is
not limited to, electric motors, inverters/converters, electronic
controllers, and associated wire harnesses and connectors, and coupling
systems for charging rechargeable energy storage systems.
* * * * *
    S5.2 Electric energy storage/conversion device retention. During
and after each test specified in S6 of this standard:
    (a) Electric energy storage/conversion devices shall remain
attached to the vehicle by at least one component anchorage, bracket,
or any structure that transfers loads from the device to the vehicle
structure, and
    (b) Electric energy storage/conversion devices located outside the
occupant compartment shall not enter the occupant compartment.
    S5.3 Electrical safety. After each test specified in S6 of this
standard, each high voltage source in a vehicle must meet the
electrical isolation requirements of subparagraph (a) or the voltage
level requirements of subparagraph (b).
    (a) The electrical isolation of the high voltage source, determined
in accordance with the procedure specified in S7.6, must be greater
than or equal to one of the following:
    (1) 500 ohms/volt for an AC high voltage source; or
    (2) 500 ohms/volt for a DC high voltage source without electrical
isolation monitoring during vehicle operation; or
    (3) 100 ohms/volt for a DC high voltage source with electrical
isolation monitoring, in accordance with the requirements of S5.4,
during vehicle operation.
    (b) The voltages V1, V2, and Vb of the high voltage source,
measured according to the procedure specified in S7.7, must be less
than or equal to 30 VAC for AC components or 60 VDC for DC components.
    S5.4 Electrical isolation monitoring. Each DC high voltage source
with electrical isolation monitoring during vehicle operation pursuant
to S5.3(a)(2) shall be monitored by an electrical isolation monitoring
system that displays a warning for loss of isolation when tested
according to S8. The system must monitor its own readiness and the
warning display must be visible to the driver seated in the driver's
designated seating position.
* * * * *
    S7.1 Electric energy storage device state-of-charge. The electric
energy storage device shall be at the state-of-charge specified in
either subparagraph (a), (b), or (c):
    (a) At the maximum state-of-charge in accordance with the vehicle
manufacturer's recommended charging procedures, as stated in the
vehicle owner's manual or on a label that is permanently affixed to the
vehicle; or
    (b) If the manufacturer has made no recommendation for charging
procedures in the owner's manual or on a label permanently affixed to
the vehicle, at a state-of-charge of not less than 95 percent of the
maximum capacity of the electric energy storage device; or
    (c) If the electric energy storage device(s) is/are rechargeable
only by an energy source on the vehicle, at any state-of-charge within
the normal operating voltage defined by the vehicle manufacturer.
    S7.2 Vehicle conditions. The switch or device that provides power
from the electric energy storage/conversion system to the propulsion
system is in the activated position or the ready-to-drive position.
* * * * *
    S7.6.1 Prior to any barrier impact test, the energy storage/
conversion system is connected to the vehicle's propulsion system, and
the vehicle ignition is in the ``on'' (propulsion system energized)
position. Bypass any devices or systems that do not allow the
propulsion system to be energized at the time of impact when the
vehicle ignition is on and the vehicle is in neutral. For a high
voltage source that has an automatic disconnect that is physically
contained within itself, the electrical isolation measurement after the
test is made from the side of the automatic disconnect connected to the
electric power train or to the rest of the electric power train if the
high voltage source is a component contained in the power train. For a
high voltage source that has an automatic disconnect that is not
physically contained within itself, the electrical isolation
measurement after the test is made from both the high voltage source
side of the automatic disconnect and from the side of the automatic
disconnect connected to the electric power train or to the rest of the
electric power train if the high voltage source is a component
contained in the power train.
* * * * *

    S7.6.4 The voltage(s) is/are measured as shown in Figure 2, and the
voltage(s) (V1) between the negative side of the high voltage source
and the electrical chassis.
    S7.6.5 The voltage(s) is/are measured as shown in Figure 3, and the
voltage(s) (V2) between the positive side of the high voltage source
and the electrical chassis.
    S7.6.6 If V1 is greater than or equal to V2, insert a known
resistance (Ro) between the negative side of the high voltage source
and the electrical chassis. With the Ro installed, measure the voltage
(V1') as shown in Figure 4 between the negative side of the high
voltage source and the electrical chassis. Calculate the electrical
isolation resistance (Ri) according to the formula shown. Divide Ri (in
ohms) by the working voltage of the high voltage source (in volts) to
obtain the electrical isolation (in ohms/volt).
    S7.6.7 If V2 is greater than V1, insert a known resistance (Ro)
between the positive side of the high voltage source and the electrical
chassis. With the Ro installed, measure the voltage (V2') as shown in
Figure 5 between the positive side of the high voltage source and the
electrical chassis. Calculate the electrical isolation resistance (Ri)
according to the formula shown. Divide Ri (in ohms) by the working
voltage of the high voltage source (in volts) to obtain the electrical
isolation (in ohms/volt).
    S7.7 Voltage measurement. For the purpose of determining the
voltage level of the high voltage source specified in S5.3(b), voltage
is measured as shown in Figure 1. Voltage Vb is measured across the two
terminals of the voltage source. Voltages V1 and V2 are measured
between the source and the electrical chassis. For a high voltage
source that has an automatic disconnect that is physically contained
within itself, the electrical isolation measurement after the test is
made from the side of the automatic disconnect connected to the
electric power train or to the rest of the electric power train if the
high voltage source is a component contained in the power train. For a
high voltage source that has an automatic disconnect that is not
physically contained within itself, the electrical isolation
measurement after the test is made from both the high voltage source
side of the automatic disconnect and from the side of the automatic
disconnect connected to the electric power train or to the rest of the
electric power train if the high voltage source is a component
contained in the power train.
    S8. Test procedure for on-board electrical isolation monitoring
system. Prior to any impact test, the requirements of S5.4 for the on-
board electrical isolation monitoring system shall be tested using the
following procedure.
    (1) The electric energy storage device is at the state-of-charge
specified in S7.1.
    (2) The switch or device that provides power from the high voltage
system to the propulsion motor(s) is in the activated position or the
ready-to-drive position.
    (3) Determine the isolation resistance, Ri, of the high voltage
source with the electrical isolation monitoring system using the
procedure outlined in S7.6.2 through S7.6.7.
    (4) Insert a resistor with resistance Ro equal to or greater than
1/(1/(95 times the working voltage of the high voltage source)-1/Ri)
and less than 1/(1/(100 times the working voltage of the high voltage
source)-1/Ri) between the positive terminal of the high voltage source
and the electrical chassis.
    (5) The electrical isolation monitoring system indicator shall
display a warning visible to the driver seated in the driver's
designated seating position.
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    Issued on: July 25, 2011.
David L. Strickland,
Administrator.
[FR Doc. 2011-19216 Filed 7-28-11; 8:45 am]
BILLING CODE 4910-59-C