82 FR 44945 - Federal Motor Vehicle Safety Standards; Electric-Powered Vehicles: Electrolyte Spillage and Electrical Shock Protection

DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration

Federal Register Volume 82, Issue 186 (September 27, 2017)

Page Range44945-44965
FR Document2017-20350

NHTSA is issuing this final rule to amend Federal Motor Vehicle Safety Standard (FMVSS) No. 305, ``Electric-powered vehicles: Electrolyte spillage and electrical shock protection,'' to adopt various electrical safety requirements found in Global Technical Regulation (GTR) No. 13, ``Hydrogen and fuel cell vehicles,'' and other sources. This final rule updates FMVSS No. 305 using modern and harmonized safety requirements and facilitates the introduction of new technologies, including hydrogen fuel cell vehicles (HFCVs) and 48-volt mild hybrid technologies. This final rule is a deregulatory action. It imposes no costs and adjusts FMVSS No. 305 to give more flexibility to manufacturers not only to use modern electrical safety designs to produce electric vehicles, but also to introduce new technologies to the U.S. market. To expand FMVSS No. 305's performance requirements beyond post-crash conditions, NHTSA adopts electrical safety requirements to protect against direct and indirect contact of high voltage sources during everyday operation of electric-powered vehicles. Also, NHTSA adopts an optional method of meeting post-crash electrical safety requirements, consistent with that in GTR No. 13, involving use of physical barriers to prevent direct or indirect contact (by occupants, emergency services personnel and others) with high voltage sources.

Federal Register, Volume 82 Issue 186 (Wednesday, September 27, 2017)
[Federal Register Volume 82, Number 186 (Wednesday, September 27, 2017)]
[Rules and Regulations]
[Pages 44945-44965]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2017-20350]


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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. NHTSA-2017-0085]
RIN 2127-AL68


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.

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SUMMARY: NHTSA is issuing this final rule to amend Federal Motor 
Vehicle Safety Standard (FMVSS) No. 305, ``Electric-powered vehicles: 
Electrolyte spillage and electrical shock protection,'' to adopt 
various electrical safety requirements found in Global Technical 
Regulation (GTR) No. 13, ``Hydrogen and fuel cell vehicles,'' and other 
sources. This final rule updates FMVSS No. 305 using modern and 
harmonized safety requirements and facilitates the introduction of new 
technologies, including hydrogen fuel cell vehicles (HFCVs) and 48-volt 
mild hybrid technologies. This final rule is a deregulatory action. It 
imposes no costs and adjusts FMVSS No. 305 to give more flexibility to 
manufacturers not only to use modern electrical safety designs to 
produce electric vehicles, but also to introduce new technologies to 
the U.S. market. To expand FMVSS No. 305's performance requirements 
beyond post-crash conditions, NHTSA adopts electrical safety 
requirements to protect against direct and indirect contact of high 
voltage sources during everyday operation of electric-powered vehicles. 
Also, NHTSA adopts an optional method of meeting post-crash electrical 
safety requirements, consistent with that in GTR No. 13, involving use 
of physical barriers to prevent direct or indirect contact (by 
occupants, emergency services personnel and others) with high voltage 
sources.

DATES: 
    Effective date: This final rule is effective September 27, 2017.
    Compliance date: The compliance date for the amendments in this 
final rule is September 27, 2018. Optional early compliance is 
permitted.
    Petitions for reconsideration: Petitions for reconsideration of 
this final rule must be received not later than November 13, 2017.

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. Note that all petitions 
received will be posted without change to http://www.regulations.gov, 
including any personal information provided.
    Privacy Act: Please see the Privacy Act heading under Rulemaking 
Analyses and Notices.

FOR FURTHER INFORMATION CONTACT: For technical issues, you may call 
William J. S[aacute]nchez, Office of Crashworthiness Standards 
(telephone: 202-493-0248) (fax: 202-493-2990). For legal issues, you 
may call Deirdre Fujita, Office of Chief Counsel (telephone: 202-366-
2992) (fax: 202-366-3820). Address: National Highway Traffic Safety 
Administration, U.S. Department of Transportation, 1200 New Jersey 
Avenue SE., West Building, Washington, DC 20590.

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. Executive Summary
    a. Overview
    b. Summary of the Final Rule and Highlighted Differences With 
the NPRM
    1. Every Day (Normal) Vehicle Operations
    i. Direct Contact Protection From High Voltage Sources
    ii. Indirect Contact Protection From High Voltage Sources
    iii. Electrical Isolation of High Voltage Sources
    iv. Monitoring Systems
    v. Electrical Safety During Charging
    vi. Mitigating Driver Error
    2. Post-Crash Safety

[[Page 44946]]

    i. Direct and Indirect Contact Protection From High Voltage 
Sources
    ii. Electrical Isolation
    3. Definitions, Figures, and Test Procedures
    4. Compliance Date
II. Background
    a. Overview of the GTR Process
    b. Overview of GTR No. 13
    c. Physical Barrier Option
    d. Petitions for Rulemaking
III. Overview of the Comments
IV. Response to the Comments
    a. Definitions and Terminology (General)
    b. Clarification of Application of Requirements
    c. Electrical Safety for Connectors and the Vehicle Charge Inlet
    d. Markings
    e. Indirect Contact Protection
    f. Electrical Isolation Requirements
    g. Electrical Safety During Charging
    h. Mitigating Driver Error
    i. Test Procedures and Figures in FMVSS No. 305
    j. Compliance Date
V. Rulemaking Analyses and Notices

I. Executive Summary

a. Overview

    NHTSA is issuing this final rule to update FMVSS No. 305, 
``Electric-powered vehicles: Electrolyte spillage and electrical shock 
protection.'' As indicated in its title, one purpose of FMVSS No. 305 
is to reduce deaths and injuries from electrical shock. Currently, the 
standard focuses on post-crash safety, requiring vehicles with high 
voltage sources to protect vehicle occupants, rescue workers and others 
who may contact the vehicle after a crash. To protect against electric 
shock, FMVSS No. 305 currently requires that, during and after the 
crash tests specified in the standard, high voltage sources in the 
vehicle must be either (a) electrically isolated from the vehicle's 
chassis \1\ or (b) their voltage must be at levels considered safe from 
harmful electric shock.\2\ This final rule amends the standard to adopt 
a physical barrier compliance option that prevents direct and indirect 
contact \3\ of high voltage sources post-crash by way of ``electrical 
protection barriers.'' An electrical protection barrier is a physical 
barrier that encloses a high voltage source to prevent direct contact 
(by occupants, emergency services personnel and others) of the high 
voltage source from any direction of access.
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    \1\ Since the physiological impacts of direct current (DC) are 
less than those of alternating current (AC), the standard specifies 
lower minimum electrical isolation requirements for DC high voltage 
sources with electrical isolation monitoring systems (100 ohms/volt) 
than for AC components (500 ohms/volt).
    \2\ Under this low voltage option, electrical components are low 
voltage if their voltage is less than or equal to 60 VDC or 30 VAC. 
VDC is the voltage for direct current sources and VAC is voltage for 
alternating current sources. These low voltage levels will not cause 
electric shock.
    \3\ Contact of a conductive part that is energized due to loss 
of electrical isolation of a high voltage source is an indirect 
contact of a high voltage source.
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    This final rule is a deregulatory action as it imposes no costs and 
adjusts FMVSS No. 305 to give more flexibility to manufacturers not 
only for current electric vehicle designs, but also for introducing new 
technologies to the U.S. market, including hydrogen fuel cell vehicles 
(HFCVs) and 48-volt mild hybrid technologies. In adopting the physical 
barrier option, this final rule adjusts the standard to remove an 
obstruction that prevented HFCVs from being offered for sale in the 
U.S. Adopting the physical barrier option also enables manufacturers to 
produce 48-volt mild hybrid systems without having to use electrical 
isolation safety measures that involve more complexity, higher consumer 
costs, and higher mass, without an incremental safety benefit. This 
rule responds to petitions for rulemaking from Toyota Motor North 
America Inc. (Toyota) \4\ and the Auto Alliance (Alliance).\5\
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    \4\ Petitioner Toyota requested the physical barrier option to 
allow HFCVs to be offered for sale in the U.S. After its submission 
of the petition for rulemaking, Toyota pursued and was granted a 
temporary exemption from FMVSS No. 305 for an HFCV (see grant of 
petition, January 2, 2015 (80 FR 101)). Toyota incorporates 
electrical protection barriers (conductively connected to the 
electric chassis with low resistance) and maintains at least a 100 
ohms/volt electrical isolation into its design. NHTSA granted the 
petition for exemption on the basis that the exemption would make 
the development or field evaluation of a low emission (zero 
emission) vehicle easier and would not unreasonably reduce the 
safety of the vehicle.
    \5\ Petitioner Alliance requested the physical barrier option to 
facilitate the production of 48volt mild hybrid technologies as well 
as HFCVs.
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    NHTSA is also issuing this final rule as part of the agency's 
ongoing effort to avoid unnecessary differences in the vehicle safety 
standards of different countries through a harmonization process under 
the United Nation Economic Commission for Europe (UNECE) 1998 Global 
Agreement (``1998 Agreement''). The efforts of the U.S.\6\ and other 
contracting parties to the 1998 Agreement culminated in the 
establishment of GTR No. 13, ``Hydrogen and fuel cell vehicles.'' NHTSA 
voted in June 2013 in favor of establishing GTR No. 13.\7\ This final 
rule adopts requirements based on the electrical safety requirements of 
GTR No. 13.\8\
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    \6\ The U.S. was one of several contracting parties to the 1998 
Agreement that proposed the development and establishment of GTR No. 
13.
    \7\ Each Contracting Party that voted for a new GTR that has 
been established under the 1998 Agreement is obligated by that 
Agreement to initiate its process for adopting the GTR into national 
law. However, the Agreement does not obligate such a Contracting 
Party to adopt the GTR. The Contracting Party retains full 
discretion under the Agreement to decide for itself whether to adopt 
the GTR.
    \8\ NHTSA is considering initiating rulemaking in the future on 
other aspects of GTR No. 13 directly pertaining to the fuel system 
integrity of HFCVs.
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    Similar to FMVSS No. 305, GTR No. 13 has requirements intended to 
reduce deaths and injuries from electrical shock, but addresses both 
normal vehicle operation and post-crash safety. Also, while the various 
post-crash compliance options in GTR No. 13 are like those in FMVSS No. 
305, GTR No. 13 includes the physical barrier option to prevent direct 
and indirect contact \9\ of high voltage sources.
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    \9\ Contact of a conductive part that is energized due to loss 
of electrical isolation of a high voltage source is an indirect 
contact of a high voltage source.
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    On March 10, 2016, NHTSA issued the notice of proposed rulemaking 
(NPRM) on which this final rule is based (81 FR 12647). The NPRM 
proposed adopting GTR No. 13's normal vehicle operation requirements, 
and proposed adopting a post-crash physical barrier compliance option 
like that in GTR No. 13.
    Comments on the NPRM were generally supportive of the proposed 
changes. Some commenters requested modifying the proposed regulatory 
text to clarify the wording of requirements and test procedures or to 
align the text with GTR No. 13 and ECE R.100, ``Uniform provisions 
concerning the approval of vehicles with regard to specific 
requirements for the electric power train,'' and some suggested NHTSA 
should not adopt some requirements for lack of safety need.
    This final rule adopts most aspects of the proposal, with some 
parts changed in response to commenters. The final rule improves motor 
vehicle safety by expanding FMVSS No. 305's protections to normal 
vehicle operations. The updated post-crash performance requirements 
ensure that new power train configurations provide a comparable level 
of post-crash safety as that of existing electric vehicles.
    This final rule reflects the state-of-the art in vehicle electrical 
safety. It draws from the findings from the agency's research on the 
physical barrier compliance option in GTR No. 13 (Battelle study),\10\ 
ECE R.100, and the

[[Page 44947]]

electrical safety requirements in a January 2014 version of SAE 
J1766.\11\
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    \10\ NHTSA contracted with the Battelle Memorial Research 
Institute to research failure modes associated with physical 
barriers that could result in electric shock. Battelle identified 
different scenarios involving failure of electrical isolation, 
direct contact protection, or indirect contact protection and a 
combination of failure of two or more these protection measures. 
Battelle then evaluated the possibility of electric shock in each of 
these scenarios. Battelle's evaluation noted that multiple failures 
in protection measures were needed for a person to experience 
electric shock. The final report is available at https://www.regulations.gov/document?D=NHTSA-2016-0029-0003.
    \11\ SAE J1766, ``Recommended practice for electric, fuel cell, 
and hybrid electric vehicle crash integrity testing,'' January 2014, 
SAE International, http://www.sae.org.
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    The rule not only gives more flexibility to manufacturers to use 
modern electrical safety designs to produce electric vehicles and 
introduce new vehicle technologies, but also paves the way globally for 
future innovations on vehicle electrical safety. A new GTR is under 
development \12\ for electric vehicle safety (EVS-GTR) which includes 
specifications for high voltage electrical components and rechargeable 
electric energy storage systems. In November 2016, NHTSA and other 
parties developing the new draft GTR completed the document's high 
voltage electrical safety provisions. The parties designed the draft 
GTR to reflect the provisions of GTR No. 13, ECE R.100, and the 
requirements proposed in the March 2016 NPRM and adopted by this final 
rule.
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    \12\ In November 2011, the Executive Committee of the 1998 
Agreement established a working group to develop a GTR for electric 
vehicle safety. The United States is a co-chair of this working 
group, along with the European Union, Japan, and China. See, draft 
Global Technical Regulation on Electric Vehicle Safety, September 
2016. https://www2.unece.org/wiki/display/trans/EVS+12th+session.
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    We estimate that the final rule will result in essentially no cost 
to consumers in the U.S. This rule adopts requirements that closely 
mirror the electrical safety provisions of GTR No. 13, which have 
already been implemented by manufacturers in this country.

b. Summary of the Final Rule and Highlighted Differences With the NPRM

    This section summarizes the requirements adopted by this final 
rule. For the convenience of the reader, we also note the few notable 
differences between this rule and the NPRM. The reasons underlying our 
decisions are explained in the body of this preamble and in the NPRM.
1. Every Day (Normal) Vehicle Operations
    This final rule adds electrical safety requirements for vehicle 
performance during every day (normal) vehicle operations to mitigate 
the risk of electric shock due to direct or indirect contact of high 
voltage sources or loss in electrical isolation. We also adopt 
requirements to assure electrical safety during refueling and to 
mitigate driver error in vehicle operation.
i. Direct Contact Protection From High Voltage Sources
    The rule specifies:
    A. IPXXD protection degree for high voltage sources inside 
passenger and luggage compartments, and IPXXB protection degree for 
high voltage sources outside passenger and luggage compartments.\13\
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    \13\ IPXXB and IPXXD ``protection degrees'' refer to the ability 
of the physical barriers to prevent entrance of a probe into the 
barrier, to ensure no direct contact with high voltage sources. 
``IPXXB'' is a probe representing a small human finger. ``IPXXD'' is 
a slender wire probe. Protection degrees IPXXB and IPXXD are 
International Electrotechnical Commission specifications for 
protection from direct contact of high voltage sources.
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    B. IPXXB protection degree for service disconnects that can be 
opened or removed without tools.\14\
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    \14\ A service disconnect is a device for deactivation of an 
electrical circuit when conducting checks and services of the 
electric battery, fuel cell stack, or other high voltage source.
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    C. Markings on certain electrical protection barriers of high 
voltage sources (i.e., barriers that can be physically accessed, 
opened, or removed without the use of tools) and on or near electric 
energy storage devices. As to the latter, the NPRM also proposed to 
require markings on or near electric energy conversion devices (fuel 
cells), but the agency concludes conversion devices are benign in and 
of themselves in that they are not high density energy sources. Thus, 
conversion devices do not need to be marked. (Note that the electric 
protection barrier around a fuel cell is required to be marked.) In 
another change from the NPRM, markings are not required on electrical 
connectors and on the vehicle charge inlet \15\ because of a lack of a 
need for the markings.
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    \15\ The vehicle charge inlet is the device on the electric 
vehicle into which the charge connector is inserted for the purpose 
of transferring energy and exchanging information from an external 
electric power supply.
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    D. In a change from the NPRM, this rule has distinct direct contact 
protection requirements for connectors and the vehicle charge inlet. 
First, it requires that the IPXXB/IPXXD protection levels be met by 
each connector when connected to its mating component. IPXXD protection 
degree is required for connectors located inside the passenger and 
luggage compartments. IPXXB protection degree is required for 
connectors and vehicle charge inlets located outside these 
compartments. Second, connectors must meet at least one of the 
following three requirements: (1) If a connector or vehicle charge 
inlet can be separated from its mating component without the use of 
tools, the IPXXB/IPXXD protection level must be provided when the 
connector is uncoupled from its mating component; (2) if a connector or 
vehicle charge inlet can be separated from its mating component without 
the use of tools, the voltage of live parts of the connector or vehicle 
charge inlet becomes less than or equal to 60 VDC or 30 VAC within one 
second of separating from its mating component; or, (3) the connector 
has a locking mechanism (at least two distinct actions are needed to 
separate the connector from its mating component), and there are other 
components that must be removed to separate the connector from its 
mating component and these cannot be removed without the use of tools.
    E. This rule requires orange color outer coverings for cables of 
high voltage sources that are located outside electrical protection 
barriers.
ii. Indirect Contact Protection From High Voltage Sources
    This rule requires exposed conductive parts of electrical 
protection barriers to be conductively connected to the chassis with a 
resistance less than 0.1 ohms, and the resistance between two 
simultaneously reachable exposed conductive parts of electrical 
protection barriers that are within 2.5 meters of each other must be 
less than 0.2 ohms.\16\
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    \16\ This ensures that in the event of loss in electrical 
isolation, no dangerous voltage potentials are produced between 
exposed conductive parts of electrical protection barriers and the 
electrical chassis, and therefore very low levels of current would 
flow through a human body contacting different parts of the vehicle. 
Since current flows through the path of least resistance, most of 
the current flow will be through the chassis than through the human 
body which has a significantly higher resistance.
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iii. Electrical Isolation of High Voltage Sources
    A. This rule requires 500 ohms/volt or higher electrical isolation 
for AC high voltage sources and 100 ohms/volt or higher for DC high 
voltage sources.
    B. Where AC and DC buses are connected, this rule permits AC high 
voltage sources to have electrical isolation of 100 ohms/volt or 
higher, provided they also have the direct and indirect contact 
protection described in i and ii, above.
iv. Monitoring Systems
    This rule requires an electrical isolation monitoring system for DC 
high voltage sources on fuel cell vehicles.

[[Page 44948]]

v. Electrical Safety During Charging
    This final rule requires:
    A. Electrical isolation greater than or equal to 500 ohms/volt 
between the electrical chassis and other high voltage sources connected 
to the vehicle charge inlet (for connecting to the AC external power 
supply). Note that this is a change from the 1 million ohms isolation 
resistance requirement proposed in the NPRM.
    B. IPXXB/IPXXD protection level for the vehicle charge inlet when 
connected to the charge connector and IPXXB/IPXXD protection level or 
low voltage when separated from the charge connector.
    C. Conductive connection of the electric chassis to earth ground 
before and during the application of exterior voltage to the 
vehicle.\17\
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    \17\ Current will flow through the path of least resistance and 
therefore most of the current resulting from a loss of electrical 
isolation would flow through the ground connection rather than 
through the human body.
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vi. Mitigating Driver Error
    This final rule includes requirements for--
    A. Providing at least a momentary indication to the driver when the 
vehicle is first placed in ``possible active driving mode'' after 
manual activation of the propulsion system.\18\ This is a change from 
the NPRM to clarify when the momentary indication must be provided.
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    \18\ Vehicles with an internal combustion engine that directly 
or indirectly provides the vehicle's propulsion power on start up 
are excluded from this requirement.
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    B. Informing the driver if the vehicle is still in a possible 
active driving mode,\19\ by an audible or visual signal when he or she 
leaves the vehicle; and,
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    \19\ I.e., the vehicle mode when application of pressure to the 
accelerator pedal or release of the brake system causes the electric 
power train to move the vehicle.
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    C. Preventing vehicle movement of more than 150 millimeters (mm) by 
its own propulsion system when the vehicle charging system is connected 
to the external electric power supply in such a way that charging is 
possible. (The 150 mm limit is a change from the NPRM, which did not 
specify a distance.)
2. Post-Crash Safety
    This final rule also amends FMVSS No. 305's post-crash electrical 
safety requirements.
i. Direct and Indirect Contact Protection From High Voltage Sources
    The rule adds an optional method of meeting post-crash electrical 
safety requirements through physical barrier protection of high voltage 
sources. The specifications of this optional method of electric safety 
include requirements ensuring that:
    A. High voltage sources are enclosed in barriers that prevent 
direct human contact with high voltage sources (IPXXB protection 
level),
    B. Exposed conductive parts of electrical protection barriers are 
conductively connected to the chassis with a resistance less than 0.1 
ohms. The resistance between any two simultaneously reachable exposed 
conductive parts of electrical protection barriers that are less than 
2.5 meters from each other must be less than 0.2 ohms.
    C. Voltage between exposed conductive parts of an electrical 
protection barrier and the electrical chassis, and between two 
simultaneously reachable exposed conductive parts of the electrical 
protection barrier that are less than 2.5 meters from each other, must 
be less than or equal to 60 VDC or 30 VAC (low voltage). (The NPRM was 
worded to apply this requirement to voltage between any exposed 
conductive parts of the vehicle.)
ii. Electrical Isolation
    An AC high voltage source that is conductively connected to a DC 
high voltage source may meet an electrical isolation requirement of 100 
ohms/volt or greater, provided the AC high voltage source also has 
physical barrier protection specified in i(A) and i(B), above.\20\ (The 
NPRM had proposed requiring all three elements i(A), i(B), and i(C) of 
physical barrier protection for such AC high voltage sources.)
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    \20\ I.e., they provide IPXXB protection degree and indirect 
contact protection of resistance between exposed conductive parts of 
the electrical protection barrier and electric chassis of 0.1 ohms 
and between two simultaneously reachable exposed conductive parts 
within 2.5 meters of each other of 0.2 ohms.
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3. Definitions, Figures, and Test Procedures
    We make minor changes to a number of proposed definitions to 
clarify the standard and to achieve consistency with other definitions. 
We adopt terms such as ``high voltage live parts,'' ``exposed 
conductive parts of electrical protection barriers,'' and ``possible 
active driving mode'' in place of proposed terms that were less clear.
    We make a minor correction to Figure 7b and clarify Figure 8.
    We clarify several test procedures, including how we will use the 
IPXXB and IPXXD protection degree probes and how we determine the 
voltage between various conductive parts. We provide manufacturers the 
option of choosing between two methods for measuring resistance, and, 
in a change from the NPRM, provide that resistance between two exposed 
conductive parts of the electrical protection barrier may be computed 
from measured resistances.
4. Compliance Date
    The compliance date for this final rule is one year from the date 
of publication of the final rule in the Federal Register. Optional 
early compliance is permitted. (The NPRM proposed a compliance date of 
180 days after the publication of the final rule in the Federal 
Register.)

II. Background

a. Overview of the GTR Process

    The United States is a contracting party to the 1998 Agreement, 
which was entered into force in 2000 and is administered by the UN 
ECE's Working Party (WP).29. The purpose of this agreement is to 
establish GTRs.
    GTR No. 13 addresses hydrogen fuel cell vehicle technology. NHTSA 
closely collaborated with experts from contracting parties to the 1998 
Agreement, particularly Germany and Japan, to develop a GTR for 
hydrogen fueled vehicles that establishes levels of safety that are 
equivalent to or exceeds those for conventional gasoline fueled 
vehicles. The collaborative effort in this process led to the 
establishment of GTR No. 13 in June 2013.
    The U.S. voted on June 27, 2013 in favor of establishing GTR No. 
13. In voting yes to establishing the GTR, NHTSA is obligated to submit 
the technical regulation to the process used in the U.S. to adopt the 
requirement into our law or regulation.\21\ By issuance of the March 
10, 2016 NPRM preceding this final rule, NHTSA initiated the process 
for considering adoption of GTR No. 13.
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    \21\ As noted above, under the terms of the 1998 Agreement, 
NHTSA is not obligated to adopt the GTR after initiating this 
process. In deciding whether to adopt a GTR as an FMVSS, we follow 
the requirements for NHTSA rulemaking, including the Administrative 
Procedure Act, the National Highway and Motor Vehicle Safety Act 
(Vehicle Safety Act) (49 U.S.C. 30101 et seq.) Presidential 
Executive Orders, and DOT and NHTSA policies, procedures and 
regulations. Among other things, FMVSSs issued under the Vehicle 
Safety Act ``shall be practicable, meet the need for motor vehicle 
safety, and be stated in objective terms.'' 49 U.S.C. 30111.
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    This final rule addresses the electrical safety requirements in GTR 
No. 13 (i.e., the electrical isolation requirements, physical barrier 
requirements, etc.) and not GTR No. 13's hydrogen fuel system and fuel 
container integrity requirements. NHTSA will commence a

[[Page 44949]]

separate proceeding on incorporating the latter portions of GTR No. 13 
into the relevant FMVSSs.

b. Overview of GTR No. 13

    HFCVs have an electric drive-train powered by a fuel cell that 
generates electric power electrochemically using hydrogen. The hydrogen 
is electrochemically combined with oxygen (from air) within the fuel 
cell system to produce high-voltage electric power. The electric power 
is supplied to the electric drive motors and/or used to charge 
batteries and capacitors. HFCVs may also be equipped with batteries to 
supplement the output of fuel cells and may also recapture energy 
during stopping through regenerative braking, which recharges batteries 
and thereby improves efficiency.
    The fuel cell provides DC power while the drive motors typically 
operate on AC. Therefore, the power train has: (a) Inverters to convert 
DC power to AC to run the motors and (b) converters to convert AC power 
generated in the drive motor during regenerative braking to DC to store 
energy in the batteries. In many respects, the electric power train of 
an HFCV is like that of electric and hybrid electric vehicles.
    GTR No. 13 specifies electrical safety requirements during normal 
vehicle operation and after a crash test, to protect against electric 
shock in the event of a failure in the high voltage propulsion system. 
GTR No. 13 includes a compliance option for electrical vehicle safety 
that prevents direct and indirect contact of high voltage sources by 
way of ``physical barriers.'' \22\
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    \22\ A detailed description of GTR No. 13 can be found in the 
NPRM. See 81 FR at 12651-12654.
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c. Physical Barrier Option

    The industry has long requested NHTSA to adopt a physical barrier 
option into FMVSS No. 305. In 2010, NHTSA decided against adoption of a 
physical barrier option because the agency believed not enough was 
known about the option.\23\ Commenters to an NPRM to upgrade FMVSS No. 
305's electrical shock protection requirements had asked NHTSA to adopt 
the option in the final rule. NHTSA declined the request,\24\ 
explaining that (a) sufficient notice might not have been provided for 
the provision, (b) the agency was uncertain whether the option would 
sufficiently account for indirect contact failure modes, and (c) the 
agency wished to pursue research on this safety approach. NHTSA 
undertook a research program (later known as the Battelle study, 
discussed in detail in the NPRM, 81 FR at 12656-12659) to better 
understand the issues related to a physical barrier option for 
electrical safety.
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    \23\ See final rule, 75 FR 33515, June 14, 2010; response to 
petitions for reconsideration, 76 FR 45436, July 29, 2011.
    \24\ Id.
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    Since that decision in 2010, several milestones ensued. GTR No. 13 
was established, a product of shared data and knowledge from governing 
bodies and international experts around the world. The Battelle study 
was completed and the physical barrier countermeasure design was made 
more robust in response to its findings, with SAE International 
revising SAE J1766 in January 2014 to set forth more protective safety 
practices than it had before. Importantly, there have now been years of 
worldwide recognition of the physical barrier option as an acceptable 
means of providing electrical safety in electric powered vehicles, with 
years of experience in design labs and in the field showing no evidence 
of associated safety problems.

d. Petitions for Rulemaking

    This final rule responds not only to GTR No. 13 but also to 
petitions for rulemaking from Toyota and the Alliance. The petitions 
are discussed in detail in the March 10, 2016 NPRM. See 81 FR at 12659-
12663.
    Petitioner Toyota believes that an additional compliance option 
that includes elements of the physical barrier option in GTR No. 13 is 
needed to allow HFCVs to be offered for sale in the U.S.
    HFCVs and other electric powered vehicles operate with their DC 
high voltage sources (e.g. high voltage battery) connected to the AC 
high voltage sources (e.g. electric motor). In a moderate to severe 
crash (e.g., crash speeds at which an air bag would deploy), electric 
powered vehicles are generally designed with an automatic disconnect 
mechanism that activates and breaks the conductive link between the 
electrical energy storage system and the rest of the power train. Under 
these crash conditions in which an automatic disconnect mechanism 
activates, Toyota states that its HFCVs would be able to meet the 
current electrical safety requirements of FMVSS No. 305. However, in 
low speed crashes where the automatic disconnect mechanism is not 
designed to activate--so that the vehicle can be driven away after a 
minor crash (fender-bender)--Toyota states that its HFCVs would not be 
able to meet the electrical safety requirements in FMVSS No. 305. The 
electrical isolation for fuel cell stacks would need to be 500 ohms/
volt or greater to comply with FMVSS No. 305, which may not be 
technically feasible. The petitioner believes that the additional 
compliance option requested in its petition would solve this problem 
and would not cause any reduction in the level of electrical safety now 
required by FMVSS No. 305.
    Petitioner Alliance requests a physical barrier compliance option 
to facilitate the production of 48-volt mild hybrid technologies as 
well as hydrogen fuel cell vehicles. The petitioner asks NHTSA to amend 
FMVSS No. 305 to adopt a physical barrier option incorporated in the 
SAE J1766 January 2014,\25\ section 5.3.4, for 48-volt mild hybrid 
systems. The Alliance believes that the provisions for physical 
barriers in section 5.3.4 incorporate the requirements of GTR No. 13 
and provide for physical barriers that ensure equal levels of safety as 
that afforded by the current FMVSS No. 305 electrical safety 
requirements.
---------------------------------------------------------------------------

    \25\ SAE J1766, ``Recommended practice for electric, fuel cell, 
and hybrid electric vehicle crash integrity testing,'' January 2014, 
SAE International, http://www.sae.org.
---------------------------------------------------------------------------

    The Alliance states that while vehicles with 48-volt mild hybrid 
systems use mostly low-voltage components that do not present any 
danger of harmful electric shock, AC voltage sources contained within 
the system can exceed the 30 volt threshold in FMVSS No. 305 for 
consideration as a high voltage source. Since these systems are 
grounded to the vehicle chassis, they cannot meet FMVSS No. 305's 
existing electrical isolation option. The petitioner states that, while 
it is feasible to design a 48-volt mild hybrid system that is isolated 
from the chassis and meets FMVSS No. 305's electrical isolation 
requirements, such designs involve more complexity, higher consumer 
costs, and higher mass resulting in reduced fuel economy and increased 
emissions. The petitioner believes that these consequences are 
inappropriate when there would be no incremental safety benefit gained 
beyond that associated with SAE J1766's physical barrier option.

III. Overview of the Comments

    NHTSA received six comments on the NPRM. Comments were received 
from two motor vehicle manufacturer associations (the Alliance and the 
Association of Global Automakers (Global)), three vehicle manufacturers 
(Mercedes-Benz USA LLC (Mercedes-Benz), Tesla Motors Inc. (Tesla), and 
Fuji Heavy Industries on behalf of Subaru of America Inc. (Subaru)), 
and one individual.
    The commenters strongly support that FMVSS No. 305 should include

[[Page 44950]]

requirements for normal vehicle operation and incorporate a physical 
barrier option for electrical safety. They request changes to the 
proposed regulatory text to improve clarity of or correct wording and 
to align the regulatory language, including definitions, to that in GTR 
No. 13 and ECE R.100. Some commenters suggest NHTSA not adopt or reduce 
the stringency of particular requirements for lack of safety need, such 
as the marking of connectors and the vehicle charge inlet, and a ``one 
million ohms'' isolation requirement for charging electrical energy 
storage devices. Several commenters suggest NHTSA adopt separate 
performance requirements for connectors and for the vehicle inlet, that 
include direct contact protection when connected and separated from its 
mating component. Some commenters request NHTSA change how the agency 
will conduct compliance tests, such as by limiting the number of 
resistance and voltage measurements between exposed conductive parts. 
Several commenters request the compliance date for the amendments be 
longer than 180 days.

IV. Response to the Comments

a. Definitions and Terminology (General)

    Commenters request modifications to certain definitions and terms 
generally used in the regulatory text. The Alliance believes that the 
definition of ``exposed conductive part'' should be revised to clarify 
that the part is not normally energized (that energization can occur 
under a fault condition). The Alliance also requests replacing the 
term, ``exposed conductive parts'' in the regulatory text with 
``exposed conductive parts of electrical protection barriers,'' so as 
to exclude conductive parts that are not part of the electrical 
protection barriers and the electric power train, such as hose clamps. 
Similarly, Global suggests the term be replaced with ``exposed 
conductive part of the electrical protection barrier enclosing the high 
voltage source,'' throughout the regulatory text. Commenters suggest 
``electrical barriers,'' should be replaced with ``electrical 
protection barriers,'' in the regulatory text for consistency and to 
reduce ambiguity. The Alliance requests a broadened definition for 
``external electric power supply,'' to refer to ``electric energy 
storage device,'' in part because the proposed definition uses the term 
``propulsion battery,'' which is not defined. The Alliance requests 
replacing the term, ``live parts'' with ``high voltage live parts'' in 
the regulatory text since electrical safety requirements apply to high 
voltage sources.
    NHTSA reviewed these comments and generally agrees with revising 
the definitions and terms at issue, to clarify the text of FMVSS No. 
305. We summarized our decisions in Table 1 and have incorporated 
appropriate changes into the regulatory text.
    The Alliance asks that we amend the definition of ``high voltage 
source'' to make clear that a component is a high voltage source based 
on its working voltage. The current definition states: ``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.'' The commenter states 
that the definition can be read in two different ways because ``it is 
not clear if the component or the electric power train is being 
modified by the given voltage limits.'' (Emphasis in text.) NHTSA's 
intent was to modify the ``component.'' \26\ We have clarified the 
definition in the regulatory text.
---------------------------------------------------------------------------

    \26\ In FMVSS No. 305, an electric component that is contained 
in the electric power train or is conductively connected to it is 
considered to be a high voltage source if its working voltage is 
greater than 30 VAC or 60 VDC. Working voltage is defined in FMVSS 
No. 305 as the highest root mean square voltage of the voltage 
source, which may occur across its terminals or between its 
terminals and any conductive parts in open circuit conditions or 
under normal operating conditions. Therefore, the reference to 
working voltage in the definition of ``high voltage source'' in 
FMVSS No. 305 is that for the electrical component and not the power 
train.
---------------------------------------------------------------------------

    The Alliance and Global point out that the definition of luggage 
compartment mistakenly refers to ``protecting the power train'' instead 
of ``protecting the occupant.'' We note that the definition's reference 
to ``hood'' should also refer to ``trunk lid,'' as in the U.S. luggage 
compartments are usually thought of as trunks, which are thought to 
have ``trunk lids.'' We have made the corrections in the text.
    The Alliance requests adding a definition for the term 
``connector,'' assuming NHTSA will adopt separate electrical safety 
requirements for connectors (this issue is discussed in a section 
below). The Alliance states that a connector is a device that provides 
mechanical connection and disconnection of high voltage electrical 
conductors to a suitable mating component, including its housing. Since 
this final rule adopts such separate requirements for connectors, the 
agency agrees to add a definition for ``connector'' to the regulatory 
text.
    The Alliance states that ``electric energy storage device'' in 
proposed S5.4.3.2 is too specific and thereby restrictive, and that 
``electric circuit'' should be used instead. We concur the proposed 
term is overly specific, but since ``electric circuit'' is not used or 
defined in FMVSS No. 305, we will use ``electric component'' in place 
of the term at issue.\27\
---------------------------------------------------------------------------

    \27\ The term, ``electric component,'' is currently used in the 
definition of a ``high voltage source'' in FMVSS No. 305.
---------------------------------------------------------------------------

    Subaru requests clarification of the meaning of the term ``normal 
vehicle operation.'' Subaru asks whether the term refers to anytime the 
vehicle is being driven under its own power or to any vehicle operation 
when no system faults or abnormalities are present. Subaru asks whether 
the reference to normal vehicle operation in the definition of the 
term, ``live parts,'' \28\ includes the vehicle's driving under its own 
electric power and static charging modes.
---------------------------------------------------------------------------

    \28\ The NPRM proposed to define live part to mean a conductive 
part of the vehicle that is electrically energized under normal 
vehicle operation (S4).
---------------------------------------------------------------------------

    NHTSA believes that ``normal vehicle operation'' includes operating 
modes and conditions that can reasonably be encountered during typical 
operation of the vehicle, such as driving, parking and standing in 
traffic, as well as, charging using chargers that are compatible with 
the specific charging ports installed on the vehicle. It does not 
include conditions where the vehicle is damaged, either by a crash or 
road debris, subjected to fire or water submersion, or in a state where 
service and or maintenance is needed or being performed.
    The Alliance, Global and Subaru ask about adding a definition for 
an ``enclosure,'' since in the NPRM the agency used the term 
``enclosure'' as though an enclosure was distinct from an electrical 
protection barrier. We meant the terms to be synonymous. However, 
rather than add the definition, for simplicity we have removed the term 
``enclosure'' from the standard and only use the term ``electrical 
protection barrier.''
    For the convenience of the reader, Table 1 below shows the notable 
added and revised terms.

[[Page 44951]]



        Table 1--Notable Terms and Definitions the Commenters Ask To Be Added or Amended; NHTSA Response
----------------------------------------------------------------------------------------------------------------
                                                                              Does NHTSA
        Term at issue            Requested change     Reason for request        agree          NHTSA response
----------------------------------------------------------------------------------------------------------------
Connector....................  NHTSA should define   Clarity; enables      Yes............  Defining the term
                                the term \29\.        distinct                               will clarify the
                                                      requirements for                       standard.
                                                      ``connectors''.
Electrical barriers..........  Use ``electrical      Consistency and       Yes............  NHTSA agrees the
                                protection            reduces ambiguity.                     same term should be
                                barriers''.                                                  used throughout the
                                                                                             standard.
Electrical protection barrier  Change the NPRM's     Clarity.............  No.............  See ``enclosure''
                                definition to make                                           (below). The change
                                clear the term                                               is unnecessary.
                                includes
                                ``enclosures''.
Enclosure....................  NHTSA should define   This term should be   No, the change   Revised the text to
                                the term.             defined since it is   is unnecessary.  remove references
                                                      used several times.                    to ``enclosure''
                                                                                             and use electrical
                                                                                             protection barrier
                                                                                             instead.
Exposed conductive part......  Add to the NPRM's     Clarify that the      Yes............  NHTSA concurs, to
                                definition to         part is not                            clarify the
                                clarify that the      normally energized;                    standard. Also, we
                                part is not           energization can                       clarify the term
                                normally energized;   occur under fault                      ``cover'' in the
                                Use ``exposed         condition. This                        definition. NHTSA
                                conductive part of    also excludes                          agrees to replace
                                the electrical        conductive parts                       ``exposed
                                protection            that are not part                      conductive part,''
                                barrier'' \30\.       of the electric                        with ``exposed
                                                      power train, such                      conductive part of
                                                      as hose clamps.                        the electrical
                                                                                             protection
                                                                                             barrier,'' in the
                                                                                             standard.
External electric power        Revise definition to  To improve accuracy   Yes............  The change clarifies
 supply.                        refer to ``electric   of the definition.                     the standard.
                                energy storage
                                device'' rather
                                than to
                                ``propulsion
                                battery''.
High voltage source..........  Revise definition as  Should make clearer   Yes............  We agree the change
                                ``means any           what is being                          clarifies the
                                electric component    modified.                              standard.
                                which is contained
                                in the electric
                                power train or
                                conductively
                                connected to the
                                electric power
                                train and has a
                                working voltage
                                greater than 30 VAC
                                or 60 VDC''.
Live parts...................  Use ``High voltage    To clarify the        Yes............  Clarifies the
                                live parts''.         applicability of                       standard.
                                                      the term.
Luggage compartment..........  Correct the           Correction..........  Yes............  We correct the
                                reference to                                                 error, and add
                                ``power train''.                                             ``trunk lid.''
Normal vehicle operation.....  NHTSA should clarify  To clarify if it      Yes............  We clarify the term
                                the term.             includes driving                       in the preamble.
                                                      and charging modes.
Electric energy storage        Use ``electric        Term is too specific  Yes, but use     ``Electric circuit''
 device (specific to.           circuit''.            and restrictive.      ``electric       is not defined.
S5.4.3.2)....................                                               component''.
----------------------------------------------------------------------------------------------------------------

b. Clarification of Application of Requirements
---------------------------------------------------------------------------

    \29\ The Alliance suggests ``a connector is a device that 
provides mechanical connection and disconnection of high voltage 
electrical conductors to a suitable mating component, including its 
housing.'' This definition was suggested by the Alliance and added 
in the draft EVS-GTR available at https://www2.unece.org/wiki/display/trans/EVS+13th+session.
    \30\ Similar to the Alliance's request, Global requests 
replacing ``exposed conductive part'' with ``exposed conductive part 
of the electrical protection barrier enclosing the high voltage 
source'' in the regulatory text. Due to the similarity with the 
Alliance's request and because there is no need to specify that 
electrical protection barriers enclose high voltage sources, 
Global's request was not adopted in the final rule.
---------------------------------------------------------------------------

    The Alliance requests we add paragraphs to the regulatory text 
explicitly stating that the electrical safety requirements (S5.3) and 
the monitoring system requirement (S5.4) of FMVSS No. 305 do not apply 
to the DC part of a 48-volt mild hybrid system. (This pertains to the 
DC part that is conductively connected to the electrical chassis and 
that has a working voltage less than or equal to 60 VDC, and the 
maximum voltage between the DC live part and any other live part is 
less than or equal to 30 VAC or 60 VDC.) The commenter states that the 
draft EVS-GTR includes such a statement.
    We do not believe there is a need for such a provision in FMVSS No. 
305, for several reasons.
    First, as discussed in a previous section, we are amending the 
definition of ``high voltage source,'' as the Alliance requests, to 
make clear that a component is a high voltage source based on its 
working voltage. That change provides the clarification the commenter 
seeks.
    Second, the Alliance asks that NHTSA provide in the preamble the 
following statement for further clarification. The commenter's 
statement is: ``Where electrical circuits, that are galvanically 
connected to each other, and fulfilling the condition, that the maximum 
voltage between a DC live part and any other live part (DC or AC) is 
less [than] or equal [to] 30 VAC and 60 VDC, only the components or 
parts of the electric circuit that operate on high voltage are 
classified as high voltage sources.'' We concur that the statement is 
consistent with NHTSA's intent.
    Third, the agency does not believe the above-quoted text is needed 
in FMVSS No. 305 because of a fundamental difference between the 
standard and the draft EVS-GTR. (This difference also exists between 
FMVSS No. 305 and GTR No. 13 and ECE R.100.) The electrical safety 
requirements in FMVSS No. 305 apply to each high voltage source in the 
power train, while the electrical safety requirements in the draft EVS-
GTR would apply to high voltage buses and electric circuits. This means 
that NHTSA determines whether the electrical safety requirements of 
FMVSS No. 305 apply to electric components that are connected to or 
part of the electric power train by individually assessing each 
component separately, analyzing its working voltage.\31\ To illustrate, 
in a 48-volt mild hybrid system, NHTSA will assess the working voltage 
of each DC component. If the working voltage of the component is not 
greater than 60 VDC, NHTSA does not subject it to the electrical safety 
requirements in FMVSS No. 305, regardless of whether it is galvanically 
connected to other electrical components that would be considered high 
voltage sources.\32\ Accordingly, the

[[Page 44952]]

additional text for excluding the DC part of 48-volt mild hybrid 
systems from electrical safety requirements requested by the Alliance 
is not necessary in FMVSS No. 305.
---------------------------------------------------------------------------

    \31\ Working voltage is defined in FMVSS No. 305 as the highest 
root mean square voltage of the voltage source which may occur 
across its terminals or between its terminals and any conductive 
part in open circuit conditions or under normal operating systems.
    \32\ In contrast, the draft EVS-GTR applies to high voltage 
buses and electric circuits. In a 48-volt mild hybrid system, the DC 
electrical sources are low voltage (working voltage is less than or 
equal to 60 VDC). The DC high voltage sources are conductively 
connected to AC electrical components such as the motor than can be 
a high voltage source (working voltage is greater than 30 VAC). 
Since the EVS draft GTR applies to high voltage buses and circuits, 
the electrical safety requirements for the high voltage source in a 
48-volt system would also apply to the DC source though it is 
considered low voltage. For this reason, specific statements are 
needed in the EVS GTR to exclude these low voltage sources from 
electrical safety requirements that are intended for high voltage 
sources.
---------------------------------------------------------------------------

c. Electrical Safety for Connectors and the Vehicle Charge Inlet

    GTR No. 13 specifies direct contact protection requirements for 
high voltage connectors separately. Per GTR No. 13, connectors do not 
need to meet IPXXB protection if they are located underneath the 
vehicle floor and are provided with a locking mechanism, or require the 
use of tools to separate the connector, or the voltage reduces to below 
30 VAC or 60 VDC within one second after the connector is separated.
    In the NPRM, NHTSA expressed disagreement with the GTR's exclusion 
of connectors under the floor. (See 81 FR at 12654-12655; id. at 
12664.) NHTSA believed that if connectors are high voltage sources and 
if they can be accessed, opened, or removed without the use of tools, 
regardless of whether they are located under the floor, they should be 
required to meet the same requirements for direct contact protection as 
other high voltage sources, including barriers providing protection 
degree IPXXD or IPXXB, based on whether they are located inside or 
outside the passenger or luggage compartment areas, respectively. 
Additionally, the agency noted that ``vehicle floor'' and ``connector'' 
are not defined in GTR No. 13.

Comments Received

    The agency received several comments on this issue. The Alliance 
and Global request the regulatory text include a separate section 
setting forth direct contact protection requirements that connectors 
and the vehicle charge inlet must meet. The Alliance suggests the 
following definition for ``connector'': ``A connector is a device that 
provides mechanical connection and disconnection of high voltage 
electrical conductors to a suitable mating component, including its 
housing.'' \33\
---------------------------------------------------------------------------

    \33\ This definition was added in the draft EVS-GTR available at 
https://www2.unece.org/wiki/display/trans/EVS+13th+session.
---------------------------------------------------------------------------

    The Alliance and Global suggest that the separate section specify 
that connectors and the vehicle charge inlet must provide protection 
degree IPXXD or IPXXB, as appropriate, when connected to its mating 
component. Further, each connector or vehicle charge inlet must also 
meet one of the following: (1) It must provide, in an uncoupled state, 
protection degree IPXXD or IPXXB, as appropriate, if the connector or 
vehicle charge inlet can be uncoupled from its mating component without 
a tool; (2) the voltage of the live parts become equal to or less than 
60 VDC or 30 VAC within 1 second after separating from its mating 
component; or (3) it has a locking mechanism that prevents the 
connector or vehicle charge inlet from being uncoupled from its mating 
component without a tool.
    In its comment, Tesla asks NHTSA to confirm whether various 
scenarios involving its connectors underneath the floor of its vehicles 
would meet the proposed requirements.\34\ Tesla requests that NHTSA 
clarify what we consider ``acceptable'' for connectors underneath the 
floor.\35\
---------------------------------------------------------------------------

    \34\ Tesla indicates that the high voltage source in its 
vehicles is located underneath the vehicle's floor, in the form of a 
battery. The commenter states this is unlike hybrid-electric 
vehicles, in which the high voltage source is located in or near the 
vehicle trunk.
    \35\ While the commenter suggested incorporating Table 4 of ISO 
6439-3, it later corrected that it meant to refer to the 2001 
version of ISO 6469-3.
---------------------------------------------------------------------------

Agency Response

    NHTSA has reviewed the comments and agrees with the recommendations 
to include separate requirements for direct contact protection of 
connectors and vehicle charge inlets. In drafting the NPRM, we 
determined that connectors were high voltage sources and that they 
should meet all the requirements for high voltage sources. However, the 
commenters provide more information about connectors, pointing out that 
they connect high voltage cables to high voltage sources through a 
mating component. Like high voltage conductors (cables), connectors 
need to have direct contact protection. But, commenters point out, 
connectors are unique in that they are designed to be disconnected from 
their mating component. Therefore, additional safety provisions are 
required to ensure the safety of this coupling and re-coupling design 
mechanism. For this reason, we have decided there is a need to specify 
unique safety provisions for connectors and vehicle charge inlets.
    We have based our final rule on the requirements suggested by the 
Alliance and Global. The requirements are harmonized with GTR No. 13, 
ECE R.100, and the draft EVS-GTR for electric vehicles. When a 
connector is connected to its mating component, it should have direct 
contact protection IPXXD or IPXXB based on whether the connector is 
inside or outside the passenger or luggage compartment, respectively. 
Additionally, connectors are required to meet at least one of the three 
following requirements: (1) It must provide protection degree IPXXD or 
IPXXB, as appropriate, in the uncoupled state, if the connector or 
vehicle charge inlet can be uncoupled from its mating component without 
a tool; (2) the voltage of the high voltage live parts become equal to 
or less than 60 VDC or 30 VAC within 1 second after separating from its 
mating component; or (3) it has a locking mechanism (at least two 
distinct actions are needed to separate the connector from its mating 
component) \36\ and there are other components that must be removed in 
order to separate the connector from its mating component and these 
cannot be removed without the use of tools.
---------------------------------------------------------------------------

    \36\ Locking mechanisms on connectors are intended to prevent 
inadvertent disconnection of the connector from its mating 
component. Locking mechanism designs include locking levers and 
screw locking. In these types of locking mechanisms, two distinct 
actions are needed to uncouple the connector. For a locking lever, 
the lever would need to be pressed down and then the connector 
pulled out. For screw locking, the connector would need to be 
unscrewed and then pulled out.
---------------------------------------------------------------------------

    Regarding Tesla's recommendation that we incorporate Table 4 of ISO 
6469-3 for connectors, we believe there is no need for such an 
amendment. ISO 6469-3 was revised in 2011 and its requirements for 
connectors are similar to those in this final rule.\37\
---------------------------------------------------------------------------

    \37\ The requirements for connectors in GTR No. 13, ECE R.100, 
and the draft EVS-GTR are also consistent with the 2011 revision of 
ISO 6469-3.
---------------------------------------------------------------------------

    Regarding Tesla's inquiry about connectors underneath the floor, 
connectors and electrical protection barriers located under the 
vehicle's floor are treated the same as other connectors and electrical 
protection barriers located outside of the passenger and luggage 
compartments.\38\ A connector located

[[Page 44953]]

under the floor that has IPXXB protection level and that cannot be 
separated from its mating component without tools would comply with the 
above direct contact protection requirements for connectors. (If it can 
be separated from its mating component without tools, it must provide 
protection degree IPXXB in the uncoupled state or the live parts must 
be equal to or less than 60 VDC or 30 VAC within 1 second from 
separating from its mating component). Regarding a connector located 
under the vehicle's floor where the access point to the connector is 
smaller than a finger could fit through, the connector would need to 
meet IPXXB protection degree if parts surrounding the connector (that 
limit access to the connector) can be opened, disassembled or removed 
without the use of tools.\39\
---------------------------------------------------------------------------

    \38\ In the NPRM, NHTSA noted that electrical protection 
barriers and connectors located under the vehicle floor should not 
be excluded from IPXXB direct contact protection and marking 
requirements because it is possible that the high voltage sources 
enclosed by these barriers and connectors may be accessed following 
a rollover crash or during vehicle maintenance. 81 FR at 12654-
12655. The agency stated in the NPRM that if connectors and 
electrical protection barriers located under the vehicle floor can 
be accessed, opened, or removed without the use of tools they should 
be required to meet the same requirements for high voltage markings 
and direct contact protection as electric protection barriers and 
connectors not located under the vehicle floor. Id.
    \39\ The test method to evaluate protection from direct contact 
with high voltage sources (S9.1) specifies that before assessing 
IPXXB or IPXXD protection degree for high voltage components, parts 
surrounding the high voltage source are opened, disassembled, or 
removed without the use of tools.
---------------------------------------------------------------------------

d. Markings

    NHTSA proposed marking requirements (yellow high voltage symbol) on 
or near electric energy storage/conversion devices, and on electrical 
protection barriers in general. We proposed that the markings would not 
be required for electrical protection barriers that cannot be 
physically accessed, opened, or removed without the use of tools. The 
proposed provisions were based on GTR No. 13 requirements, but unlike 
GTR No. 13, the NPRM did not exclude from the marking requirement (1) 
electrical protection barriers or high voltage sources located under 
the vehicle floor; (2) connectors generally; or (3) the vehicle charge 
inlet. NHTSA also proposed that cables for high voltage sources that 
are not located within electrical protection barriers must be 
identified by an orange colored outer covering.

Comments Received

    The agency received multiple comments on this issue.
    The Alliance, Global and Subaru request that connectors be excluded 
from the marking requirement. The Alliance and Global state that some 
connectors can be so small that the markings on these connectors would 
be not easily read and that high voltage cables going into the 
connectors are required to have orange outer covers, which should 
signal that the cables and their connectors are high voltage. The 
Alliance also notes that high voltage connectors do not necessarily 
carry high current. The Alliance states that the inclusion of a marking 
requirement for connecters would necessitate product development 
efforts, increased economic cost and compliance burden, without a 
commensurate increase in safety.
    Subaru believes that markings should not be necessary on or near 
electric storage/conversion devices which are not in plain view of 
vehicle occupants during normal vehicle operation. Subaru states that a 
device that is mounted under a seat, and that is not visible without 
first removing the seat, should not have to be marked.
    Tesla believes that high voltage sources underneath the vehicle are 
subject to a harsh physical environment, and that the markings on them 
are not likely to survive the vehicle's life. Tesla asks NHTSA to allow 
for alternative placement of high voltage markings when a vehicle's 
high voltage source is located under the vehicle's floor.

Agency Response

    The agency agrees with the Alliance and Global request to exclude 
connectors from requiring markings. The agency is persuaded by the 
commenters that connectors do not necessarily carry high current and 
that the increased economic cost and compliance burden resulting from a 
marking requirement are not warranted. The connectors are small, so 
markings on them would not be easily read. Further, we agree that since 
high voltage cables going into the connectors are required to have 
orange outer covers, those covers will sufficiently indicate that the 
cables and their connectors are high voltage. Importantly, the markings 
are also not needed because, in a change from the NPRM, we have decided 
to require connectors to have direct contact protection when connected 
and disconnected from their mating component. (As discussed above, the 
direct contact protection consists of IPXXD or IPXXB protection when 
connected to the mating component, and at least one of the following: 
(1) IPXXD or IPXXB protection when separated from its mating component 
if the connector can be uncoupled without a tool; (2) a low voltage 
requirement within 1 second after separation from its mating component; 
or (3) it cannot be uncoupled from its mating component without the use 
of tools. Thus, we conclude that connectors will sufficiently protect 
against the risk of electrical shock without the markings.
    Similarly, the agency also agrees with the Alliance and Global 
request to exclude the vehicle charge inlet from requiring markings. 
The markings are not necessary because this final rule requires vehicle 
charge inlets to have direct contact protection when connected and 
disconnected from their mating component, like connectors.
    The agency does not agree with Subaru's request to omit the high 
voltage marking on electric energy storage/conversion \40\ devices that 
are not in plain view of vehicle occupants during normal vehicle 
operation. GTR No. 13, ECE R.100, and the draft EVS-GTR require the 
high voltage symbol on or near electric energy storage devices. Since 
an electric energy storage device is a high density energy source, we 
believe there is a safety need for the marking, as persons (such as 
maintenance, repair and rescue personnel and consumers working on their 
vehicles) encountering the electric energy storage device should be 
warned of the electrical shock risks. However, we are revising the 
proposed regulatory text to indicate that the marking on electric 
energy storage devices ``shall be present'' rather than ``shall be 
visible.'' This terminology is consistent with the draft EVS-GTR. The 
final rule's wording (``shall be present'') acknowledges that the 
marking is not, and does not have to be, ``visible'' on an electric 
energy storage device when the device is located under the floor away 
from view.
---------------------------------------------------------------------------

    \40\ We do not agree with the idea of excluding a device from 
the marking requirements simply because the device is not in plain 
view of the occupants. However, as discussed further below, we are 
omitting the marking requirement generally for electric energy 
conversion devices. The rest of this response to Subaru pertains to 
marking electric energy storage devices.
---------------------------------------------------------------------------

    Thus, under this final rule, the electric energy storage device 
must be marked, and the electrical protection barrier for the device 
must also be marked with a visible high voltage symbol if it can be 
accessed, opened, and removed without the use of tools. To illustrate, 
if an electric energy storage device is accessible when the floor mat 
is pulled out and a floor panel is opened (without the use of tools), 
the floor panel has to have a high voltage symbol that is visible to 
the person when he/she pulls out the floor mat.
    NHTSA has decided not to require electric energy conversion devices 
to be marked with the high voltage symbol. Electric energy conversion 
devices include fuel cells which convert chemical energy to electric 
energy. A fuel cell only becomes a high voltage source when hydrogen is 
supplied to it. Since conversion devices (e.g., fuel cells) are not 
high density energy sources, we are not requiring them to be

[[Page 44954]]

marked. However, the electric protection barrier around a conversion 
device (e.g., fuel cell) will have to be marked, and the mark is 
required to be visible.
    NHTSA does not agree with Tesla's request to allow alternative 
positions for the high voltage symbol mark on high voltage sources that 
are located underneath the vehicle's floor. We do not believe there is 
a need for the change as the regulatory text requires that the mark be 
``on or near'' electric energy storage devices without providing 
specifics for the location of the high voltage marking. We note also 
that this final rule provides that electrical protection barriers that 
cannot be physically accessed, opened, or removed without the use of 
tools are excluded from the marking requirement,\41\ which may bear on 
Tesla's labeling of its devices.
---------------------------------------------------------------------------

    \41\ Markings are not required on electrical protection barriers 
that cannot be physically accessed, opened, or removed without the 
use of tools. The persons who will access the powertrain with tools 
will be maintenance personnel technically aware of the vehicle's 
electrical system, and not first responders. We believe that 
maintenance personnel will have basic knowledge of the workings of 
the electrical system, so the electrical shock warning symbol is not 
necessary.
---------------------------------------------------------------------------

e. Indirect Contact Protection

    Exposed conductive parts of electrical protection barriers must be 
protected against indirect contact \42\ during normal vehicle operation 
and post-crash. The NPRM proposed that the resistance between exposed 
conductive parts of electrical protection barriers and the electrical 
chassis must be less than 0.1 ohms and that the resistance between any 
two simultaneously reachable exposed conductive parts of electrical 
protection barriers that are within 2.5 meters of each other be less 
than 0.2 ohms (proposed S5.3(c)(2)). The NPRM also proposed 
(S5.3(c)(3)) that the voltages between an electrical protection barrier 
and other exposed conductive parts must be less than or equal to 30 VAC 
or 60 VDC (``low voltage requirement''). These proposed requirements 
would protect against electric shock if any electrically charged 
components lose isolation within the protective barrier and two exposed 
conductive parts of the electrical protection barrier are contacted 
simultaneously, by shunting \43\ any harmful electrical current to the 
vehicle chassis.
---------------------------------------------------------------------------

    \42\ Indirect contact refers to the contact of persons with 
exposed conductive parts.
    \43\ Shunting is when a low-resistance connection between two 
points in an electric circuit forms an alternative path for a 
portion of the current. If a human body contacts an electrical 
protection barrier that is energized due to loss in electrical 
isolation of a high voltage source enclosed in the barrier, most of 
the current would flow through the chassis rather than through the 
human body because the current path through the chassis has 
significantly lower resistance (less than 0.1 ohm) than the 
resistance of the human body (greater or equal to 500 ohm).
---------------------------------------------------------------------------

Comments Received

    Global comments that the reference to ``any two simultaneously 
reachable exposed conductive parts'' in proposed S5.3(c)(2) ``would 
result in excessive testing requirements, due to the number of 
potential combinations of two simultaneously reachable exposed parts.'' 
The commenter recommends that manufacturers be authorized to identify a 
``worst case'' pair of conductive parts for testing under the provision 
to reduce the potential number of combinations. Global also recommends 
that greater specification for the phrase ``any two simultaneously 
reachable,'' be provided, such as a measured distance.

Agency Response

    NHTSA believes that the regulatory text already provides the 
specification that the simultaneously reachable exposed conductive 
parts of electrical protection barriers must be located within 2.5 
meters of each other. Thus, we do not believe the requirement results 
in an excessive number of resistance measurements. However, NHTSA is 
correcting the reference to ``exposed conductive parts of the 
electrical protection barriers'' in S5.3(c)(2) to qualify that they are 
exposed conductive parts of the electrical protection barrier of the 
high voltage source under consideration in S5.3.

Comments Received

    Global comments that the low voltage requirement (S5.3(c)(3)) is 
too broad in scope and recommends limiting this testing requirement to 
exposed conductive parts of the electrical protection barriers. Global 
states that in the event of a barrier failure, a voltage differential 
could exist with regard to all exposed conductive parts of the chassis 
and all metal parts connected to the chassis. The Alliance comments 
that the requirements in S5.3(c)(3) should be consistent with the 
requirement in S5.3(c)(2). I.e., the Alliance believes that the voltage 
measurements for S5.3(c)(3) between exposed conductive parts should be 
made on the same exposed conductive parts of electrical protection 
barriers for which resistance measurements are made for S5.3(c)(2).

Agency Response

    The agency agrees with the comments of Global and the Alliance and 
has worded S5.3(c)(3) to reflect the recommended changes. As adopted, 
S5.3(c)(3) specifies that the voltage between exposed conductive parts 
of the electrical protection barrier and the electrical chassis must be 
less than or equal to 30 VAC or 60 VDC.\44\ In addition, the voltage 
between an exposed conductive part of the electrical protection barrier 
and any other simultaneously reachable exposed conductive parts of 
electrical protection barriers within 2.5 meters of it must be less 
than or equal to 30 VAC or 60 VDC.
---------------------------------------------------------------------------

    \44\ In the NPRM, S5.3(c)(3) was worded such that the voltage 
measurements were between the electrical protection barrier and 
``other exposed conductive parts,'' which includes the electrical 
chassis. Since in this final rule we have modified the proposed 
wording of S5.3(c)(3) to make the voltage measurements between 
exposed conductive parts of electrical protection barriers (in 
response to Global's comment), the agency has separately added a 
requirement to S5.3(c)(3) to account for the voltage measurement 
between exposed conductive parts of the electrical protection 
barrier and the electrical chassis. This change in the language of 
S5.3(c)(3) makes it more consistent with the language of S5.3(c)(2) 
and is not a substantive change from the NPRM.
---------------------------------------------------------------------------

f. Electrical Isolation Requirements

    Under FMVSS No. 305's current post-crash safety requirements, 
vehicles must meet either electrical isolation requirements or low 
voltage requirements. The current requirements for electrical isolation 
are that the electrical isolation of the high voltage source must be 
greater than or equal to: 500 ohms/volt for an AC high voltage source; 
500 ohms/volt for a DC high voltage source without electrical isolation 
monitoring during vehicle operation; or 100 ohms/volt for a DC high 
voltage source with an electrical isolation monitoring system during 
vehicle operation.
    The NPRM proposed to change these requirements (S5.3(a)) and add 
specifications that high voltage sources must have electrical isolation 
during normal vehicle operation (S5.4.3.1). Briefly, the proposed 
electrical isolation requirements are: AC high voltage sources have 500 
ohms/volt or higher electrical isolation from the electric chassis; DC 
high voltage sources have 100 ohms/volt or higher electric isolation 
from the electric chassis; or, AC high voltage sources that are 
conductively connected to the DC high voltage sources may have 100 
ohms/volt or higher electrical isolation from the electric chassis 
provided they also provide physical barrier protection.

[[Page 44955]]

Comments Received and Agency Response

    The Alliance first requests that the regulatory text of the 
electrical isolation option under post-crash conditions (S5.3(a)) and 
during normal vehicle operating conditions (S5.4.3.1) be replaced by 
the language in GTR No. 13.
    The agency declines this request. The requirements of the 
electrical isolation option in FMVSS No. 305 and GTR No. 13 are 
identical, while the text in FMVSS No. 305 is more concise.
    Second, the Alliance requests changes to the proposed physical 
barrier protection requirements for AC high voltage sources that are 
conductively connected to DC high voltage sources and that comply with 
the lower electrical isolation limit of 100 ohms/volt under post-crash 
conditions (S5.3(a)(2)). The proposed text in the NPRM permits an AC 
high voltage source to have an isolation resistance of only 100 ohms/
volt if three physical protection requirements are met.\45\ The 
Alliance suggests that the low voltage requirement is ``not logically 
needed.'' It states that the electric shock scenario identified in 
NHTSA's Battelle study \46\ of physical barriers will never happen if 
it maintains a minimum electrical isolation of more than 100 ohms/volt, 
protection against direct contact (IPXXB), and protection against 
indirect contact (resistance between exposed conductive parts and the 
electrical chassis and between two exposed conductive parts of less 
than 0.1 ohms and 0.2 ohms, respectively).
---------------------------------------------------------------------------

    \45\ These are proposed as: (1) IPXXB protection level 
(S5.3(c)(1)), (2) resistance between exposed conductive parts of the 
electrical protection barrier and chassis of less than 0.1 ohms and 
between any two simultaneously reachable exposed conductive parts of 
barriers less than 2.5 m apart of less than 0.2 ohms (S5.3(c)(2)), 
and (3) the voltage between electrical protection barrier enclosing 
the high voltage source and other exposed conductive parts of less 
than or equal to 30 VAC or 60 VDC (``low voltage requirement'') 
(S5.3(c)(3)).
    \46\ Supra. The NPRM discusses the Battelle study in detail, see 
81 FR at 12656.
---------------------------------------------------------------------------

    NHTSA has carefully analyzed electrical safety implications under 
the conditions of a minimum electrical isolation of 100 ohms/volt, 
resistance between exposed conductive parts of electrical protection 
barriers and the chassis of 0.1 ohms, and electrical isolation between 
two exposed conductive parts of 0.2 ohms. The results of the analysis 
\47\ showed that under these conditions, the electric current through 
the body would be significantly lower than 10 milliamps (mA) DC and 2 
mA AC, which are considered safe levels of current for protection from 
electric shock. Therefore, the agency agrees to this change in the 
regulatory text requested by the Alliance. Accordingly, S5.3(a)(2) is 
modified so that AC high voltage sources that are conductively 
connected to DC high voltage sources may comply with the lower 
electrical isolation limit of 100 ohms/volt provided they meet the 
physical protection requirements of S5.3(c)(1) and S5.3(c)(2).
---------------------------------------------------------------------------

    \47\ We have docketed a memorandum showing our analysis. See the 
docket for this final rule.
---------------------------------------------------------------------------

g. Electrical Safety During Charging

    Like GTR No. 13, the NPRM proposed (S5.4.5) to require electric 
vehicles whose rechargeable energy storage system are charged by 
conductively connecting to a grounded external power supply to have a 
device to enable conductive connection of the electrical chassis to the 
earth ground during charging. This proposal was to ensure that in the 
event of electrical isolation loss during charging, a person contacting 
the vehicle does not form a ground loop with the chassis and sustain 
significant electric shock. Additionally, like GTR No. 13, the NPRM 
proposed (S5.4.3.3) to require the isolation resistance between the 
high voltage source and the electrical chassis to be at least 1 million 
ohms when the charge coupler is disconnected. This proposal was to 
ensure that the magnitude of current through a human body when a person 
contacts a vehicle undergoing charging is low and in the safe zone.

Comments Received

    The agency received many comments regarding the requirement for 
isolation resistance of 1 million ohms during charging.
    The Alliance states that the requirement should only be applicable 
to conductive charging with an AC external electric power supply, 
noting that the isolation resistance of one million ohms should be 
required for the high voltage source (high voltage buses) that are 
conductively connected to the contacts of the vehicle charge inlet, and 
not to the vehicle charge inlet itself.
    Mercedes-Benz states that the 1 million ohms isolation resistance 
specification--

    is intended as a system reliability requirement, not a safety 
requirement. The safety relevant requirements on an isolation 
resistance are already specified in S5.4.3.1. . . . [T]he regulatory 
text [should] explicitly remove the `one million ohm' specification 
and instead state that the isolation resistance, measured at the 
vehicle charge inlet, must comply with the requirements stated in 
S5.4.3.1.

    Tesla states that it does not believe the insulation resistance 
requirement for the vehicle's inlet is aligned with the associated high 
voltage hazards that the NPRM proposes to mitigate. Tesla believes that 
the intent of the insulation resistance requirement is to prevent high 
voltage current from flowing through the human body. Tesla believes 
that Section 11.7 of the IEC 61851-1:2010 \48\ more accurately captures 
this prevention for AC equipment because it specifically applies to 
cord and plug-connected equipment. Tesla also recommends that NHTSA 
``provide clear requirements for off-board (including charging) 
equipment(s)'' since any fault current that is generated while charging 
would be a function of both the vehicle as well as the electric vehicle 
supply equipment.
---------------------------------------------------------------------------

    \48\ IEC 61851-1:2010, ``Electric vehicle conductive charging 
system--Part I: General Requirements,'' https://webstore.iec.ch/publication/6029.
---------------------------------------------------------------------------

Agency Response

    To evaluate these comments, NHTSA requested information from 
technical experts in the working group for the draft EVS-GTR on 
electric vehicle safety, in which NHTSA participates. Technical 
information was provided by Mr. Takahiko Miki \49\ from the 
Organisation Internationale des Constructeurs d'Automobiles (OICA).\50\ 
Mr. Miki noted that the one million ohms electrical isolation 
requirement is from IEC 61851-1. Mr. Miki also noted that the 
requirements in IEC 61851-1 apply to conductive charging of electric 
vehicles with an AC external electric power supply.
---------------------------------------------------------------------------

    \49\ Miki, T., ``Personal Protection during Charging.'' 
Submitted at the 12th EVS GTR meeting in Paris on September 15, 
2016, EVSTF09-32-TF2-04.docx. https://www2.unece.org/wiki/display/trans/9th+Task+Force+meetings+in+Paris.
    \50\ OICA is an international organization of motor vehicle 
manufacturers whose members include 39 national trade associations 
around the world.
---------------------------------------------------------------------------

    Mr. Miki provided the following detailed explanation of protective 
measures in vehicles during charging to prevent electric shock. Mr. 
Miki noted that protection against electric shock during charging by 
connecting to an AC external electric power supply is provided by the 
vehicle and the off-board electric vehicle supply equipment (i.e. 
charge connector) and provided a description of these protection 
systems. Protection systems in the vehicle include: (1) Protection 
against direct contact with high voltage live parts and (2) indirect 
contact protection from high voltage sources (equipotential bonding--
earthing/grounding). Protection systems in the electric vehicle supply 
equipment (charge connector) include: (1) Earthing/grounding conductor 
between the electrical chassis of a vehicle and the

[[Page 44956]]

earth/ground, (2) earthing/grounding continuity monitor, and (3) 
automatic disconnection of supply (residual current device (RCD),\51\ 
charging circuit interrupting device (CCID) \52\ located in the charge 
electric vehicle supply equipment or in the fixed electrical 
installation, or both) operated by the fault current that disconnects 
one or more of the line conductors.
---------------------------------------------------------------------------

    \51\ RCD is a mechanical switching device designed to make, 
carry and break currents under normal service conditions and to 
cause the opening of the contacts when the residual current attains 
a given value under specified conditions. A residual current device 
can be a combination of various separate elements designed to detect 
and evaluate the residual current and to make and break current. 
[Source: IEC 61851-1, IEV 442-05-02]
    \52\ CCID is a device that continuously monitors the 
differential current among all of the current-carrying line 
conductors in a grounded system and rapidly interrupts the circuit 
under conditions where the differential current exceeds the rated 
Measurement Indication Unit (MIU) value of a charging circuit 
interrupting device. The device is identified by the letters CCID 
followed by the differential trip current rating of either 5 or 20 
indicating the tripping rating in MIU. [Source: UL 2231-1]
---------------------------------------------------------------------------

    The AC external electric power supply is grounded to earth ground. 
When an electric vehicle is connected to the AC external electric power 
supply by the charge connector, the vehicle electrical chassis is 
connected to the earth/ground through the earthing/grounding conductor. 
If electrical isolation/insulation is lost during charging, the leakage 
current (residual current) \53\ would flow to the earth/ground through 
the earthing/grounding conductor. Under such conditions, a human body 
contacting high voltage-exposed conductive parts of the vehicle would 
not experience electric shock if the leakage current is less than or 
equal to maximum current levels considered to be safe. If the leakage 
current reaches or exceeds specified safety threshold levels, the RCD/
CCID would open the circuit to interrupt the supply of electric energy. 
A similar form of this type of electric shock protection measure is 
provided in homes for use of common household electric equipment.
---------------------------------------------------------------------------

    \53\ Leakage current is the current flowing through ground due 
to a fault condition. The magnitude of leakage current is determined 
as the difference in the current flowing through the positive 
terminal and that returning on the negative terminal. Therefore, it 
is also referred to as residual current.
---------------------------------------------------------------------------

    The electrical isolation of high voltage sources that are connected 
to the vehicle charge inlet during charging by connecting the AC 
external electric power supply is determined based on the 
characteristics of the RCD/CCID to ensure that leakage current would be 
significantly lower than the leakage current level that would trip the 
RCD/CCID to open the circuit. This electrical isolation requirement is 
not for electric shock protection but to ensure that charging is not 
interrupted under normal charging conditions. Mr. Miki recommends that 
the electrical isolation between the electrical chassis and high 
voltage sources that are conductively connected to the vehicle charge 
inlet during AC charging be greater than or equal to 500 ohms/volt 
because with this level of electrical isolation, the leakage current 
would be sufficiently lower than the leakage (residual) current level 
that would trip the RCD/CCID to open the circuit and interrupt the 
electric energy supply.\54\
---------------------------------------------------------------------------

    \54\ For DC charging, the power input to the vehicle is isolated 
from the ground by the isolation transformer. Therefore, electric 
shock protection is maintained even if isolation resistance is 
reduced (fault condition), because the current loop to the ground is 
not established. Additionally, DC charging stations monitor the 
combined isolation resistance of the vehicle and the electric 
vehicle supply equipment. If the DC charging station detects that 
the combined isolation resistance is lower than the specified value 
(for electric shock protection), the DC output cable is not 
energized (power supply is terminated).
---------------------------------------------------------------------------

    In light of the new information provided by Mr. Miki and the 
commenters, the agency is modifying the proposed isolation resistance 
requirement for high voltage sources for charging the electric energy 
storage device (S5.4.3.3). High voltage sources conductively connected 
to the vehicle charge inlet during charging (through conductive 
connection to the AC external electric supply) are required to have 
electrical isolation from the electric chassis of 500 ohms/volt when 
the charge connector is disconnected.
    We believe the modified language responds to the comments from the 
Alliance, Mercedes-Benz, and Tesla. Additionally, the modified 
requirement is consistent with that developed in the draft EVS-GTR for 
electric vehicles.
    Regarding Tesla's recommendation for NHTSA to provide clear 
requirements for off-board (including charging) equipment, the agency 
is looking into this matter. The safety measures in the electric 
vehicle supply equipment, such as the RCD/CCID in the charge connector, 
are specified in the National Electric Code (NEC)--Article 625: 
Electric Vehicle Charging System and in the Underwriters Laboratory 
(UL) 2954, ``Electric vehicle supply equipment.'' Adding requirements 
for off-board equipment is not in scope of this final rule since the 
agency did not include any such requirements in the NPRM. The agency 
may consider the need for and the feasibility of requirements for off-
board electric vehicle equipment in the future.

h. Mitigating Driver Error

    NHTSA proposed three provisions for mitigating the likelihood of 
driver error in operating electric vehicles (S5.4.6). First, the 
heading and text of proposed S5.4.6.1 proposed that at least a 
momentary indication shall be given at ``start up'' when the vehicle is 
in a possible active driving mode.\55\ (``Start up'' is also used in 
GTR No. 13.) Second, the NPRM proposed that drivers be provided an 
audible or visual signal if the vehicle is still in the possible active 
driving mode when the driver leaves the vehicle. Third, for vehicles 
that have on-board electric energy storage devices that can be charged 
externally, the NPRM proposed to prohibit vehicle movement by the 
vehicle's own propulsion system when the external electric power supply 
is physically connected to the vehicle charge inlet.
---------------------------------------------------------------------------

    \55\ ``Possible active driving mode'' is the vehicle mode when 
the application of pressure to the accelerator pedal or release of 
the brake system causes the electric power train to move the 
vehicle.
---------------------------------------------------------------------------

Comments Received and Agency Response

    The agency received comments from Global, the Alliance and Tesla on 
the proposal. Global requests a clarification of the meaning of ``start 
up'' used in the first provision. Global asks if ``start up'' refers to 
the time of engine start or some other meaning.
    NHTSA meant ``start up'' to refer to the time when the vehicle is 
first placed in a possible active driving mode (e.g., reverse, drive, 
or other driving gears) after manual activation of the propulsion 
system. The provision at issue is intended to reduce operational errors 
that could have safety implications. For example, a driver might not 
realize the vehicle is in an active driving mode when he or she pressed 
on the accelerator pedal, which could result in a potential crash 
condition. However, to reduce ambiguity, we have modified the final 
rule regulatory text by replacing the phrase, ``upon start up,'' with 
the phrase, ``when the vehicle is first placed in possible active 
driving mode after manual activation of the propulsion system.'' Once 
driving is initiated, notification is not needed when the vehicle is 
put in neutral to change gears (for manual-drive vehicles).
    The Alliance believes the heading of the third provision for 
mitigating driver error should be revised from ``Prevent drive-away 
during charging'' to ``Prevent drive-away'' to reflect that the concern 
is that the driver may drive the vehicle away after charging is

[[Page 44957]]

completed without disconnecting the charge connector. The Alliance also 
notes that a simple physical connection without any conductive 
connection may not be detected by vehicle systems. The commenter 
recommends changing the phrase, ``physically connected to the vehicle 
charge inlet,'' to ``physically connected to the vehicle charge inlet 
in such a way that charging is possible.''
    The agency agrees generally with the Alliance's recommended changes 
and has changed the proposed regulatory text. We believe the changes 
improve clarity and removes ambiguity about when and under what 
conditions the requirement to prevent vehicle movement applies.\56\
---------------------------------------------------------------------------

    \56\ If the charge connector is not connected correctly to the 
vehicle charge inlet, then charging may not even initiate and 
driving away with the charge connector physically connected would 
not result in an electric safety hazard.
---------------------------------------------------------------------------

    Tesla states that the phrase, ``preventing physical vehicle 
movement by its own power,'' is vague and needs clarification. Tesla 
requests that the agency draw a clear distinction between when a 
vehicle is considered stationary and when it is in ``movement under its 
own power.'' The commenter suggests using a provision in FMVSS No. 114, 
``Theft protection and rollaway prevention.'' S5.2.5 of FMVSS No. 114 
specifies that a vehicle must not move more than 150 mm on a 10 percent 
grade when the gear selection control is locked in ``park.''
    The agency sees merit in Tesla's suggestion to improve objectivity 
of the requirement for preventing vehicle movement when the charge 
connector is connected to the vehicle charge inlet. S5.2 in FMVSS No. 
114 specifies provisions to prevent rollaway in vehicles equipped with 
a transmission with a ``park'' position. One provision is that when the 
vehicle is resting on a 10 percent grade and the vehicle's gear 
selection control is locked in ``park,'' the vehicle must not move more 
than 150 mm when the brakes are released. To distinguish minor 
vibrations of the vehicle when it is idling from vehicle movement 
``under its own power,'' the agency is modifying the proposed 
regulatory text to state that the vehicle must not move more than 150 
mm \57\ by its own propulsion system when the charge connector is 
physically connected to the vehicle charge inlet in such a way that 
charging is possible.
---------------------------------------------------------------------------

    \57\ Vehicle movement of 150 mm is deemed sufficiently low such 
that the charge connector would not disengage from the vehicle inlet 
or damage the charging equipment.
---------------------------------------------------------------------------

i. Test Procedures and Figures in FMVSS No. 305

    The NPRM proposed test procedures for evaluating IPXXB and IPXXD 
direct contact protection (S9.1), measuring resistance between exposed 
conductive parts and between an exposed conductive part and the 
electrical chassis to evaluate indirect contact protection (S9.2), and 
measuring voltage between exposed conductive part of an electrical 
protection barrier and the electrical chassis or any other exposed 
conductive part of the vehicle for indirect contact protection (S9.3).
    For evaluating direct contact protection, the proposed test 
procedure in S9.1 detailed how the IPXXB and IPXXD probes are used and 
manipulated to determine if high voltage live parts are contacted. 
Subaru comments that the description of manipulating the IPXXB finger 
probe does not specifically note that it is only applicable to the 
IPXXB probe and not the IPXXD probe. NHTSA agrees and has corrected 
this omission to indicate that the described manipulation of the finger 
probe only applies to the IPXXB probe.
    In proposed S9.1 the NPRM did not explicitly provide criteria for 
assessing whether high voltage live parts were contacted, though such 
information is provided in GTR No. 13. To make S9.1 clearer, and to 
better harmonize the test procedure in FMVSS No. 305 with that in GTR 
No. 13, the criteria for verification of IPXXD and IPXXB protection 
degree in GTR No. 13 are included in the regulatory text.
    For measuring resistance between two exposed conductive parts, the 
NPRM at S9.2 provided two methods that could be used. Global states 
that the two methods were provided in GTR No. 13 as compliance options 
for manufacturers to select for evaluating indirect contact protection. 
The commenter recommends we include regulatory text to make clear that 
it is at the manufacturer's option to choose either test method to 
certify compliance. The agency agrees that the two methods were 
provided as compliance test options for manufacturers and has included 
the recommended regulatory text in S9.2 of FMVSS No.305.
    Global expresses concern that provisions for indirect contact 
protection in S9.2 create an inordinate certification burden on 
manufacturers due to the phrase, ``any two exposed conductive parts.'' 
The commenter requests that instead of measuring the resistance between 
two exposed conductive parts, resistance may be calculated using the 
separately measured resistances of the parts of the electrical chassis.
    NHTSA agrees with this requested change from Global. The agency 
notes that GTR No. 13, ECE R.100, and the draft EVS-GTR permit 
resistances to be calculated using the separately measured resistances 
of the relevant parts in the electric path. NHTSA believes that a 
calculation option is acceptable for the requirement at issue because 
resistances can be computed from other measured resistances on an 
actual vehicle in a straightforward manner, and do not involve 
potentially subjective judgment calls on the part of evaluators as to 
whether assumptions underlying a calculation are merited.
    For measuring voltage between exposed conductive parts of 
electrical protection barriers, the NPRM specified a method in which 
the DC power supply, voltmeter, and ammeter are connected between 
measuring points. The Alliance and Global point out that the DC power 
supply should not be connected in this test (S9.3a). The agency agrees 
and has corrected the regulatory text. Additionally, NHTSA believes 
that calculating the voltage between two exposed conductive parts from 
the measured voltages between the exposed conductive parts and the 
electrical chassis is straightforward and unambiguous and so is 
permitting a calculation option for determining voltage between exposed 
conductive parts.
    The proposal provided specifications of the IPXXB probe in Figure 
7b of the regulatory text. The Alliance and Global note errors in the 
specification for R2 and R4. The agency has corrected the errors in 
Figure 7b.
    The Alliance and Global provide an improved Figure 8 in which the 
text is clearer than the NPRM's Figure 8. The agency has included the 
new figure in FMVSS No. 305.

j. Compliance Date

    The NPRM proposed a compliance date of 180 days after the date of 
publication of the final rule in the Federal Register, with optional 
early compliance permitted.
    The Alliance states that, although the proposed amendments to FMVSS 
No. 305 are vital to enable the production of advanced fuel cell and 
48-volt mild hybrid vehicles, the ``in use'' requirements may require 
some modification of currently-certified electric vehicles. The 
commenter asks that the compliance date be modified to align it with 
the first September 1st that is at least 180 days after the publication 
of the final rule in the Federal Register, with optional early 
compliance

[[Page 44958]]

permitted. An individual, Mr. Albert Torres, also believes that a 
longer compliance date should be provided.

Agency Response

    The agency believes that most, if not all, electric-powered 
vehicles currently sold in the United States would be able to comply 
with the updated requirements in FMVSS No. 305 by the proposed 
compliance date. However, as noted by the Alliance, some vehicles may 
need some minor modifications to comply with some of the modifications 
in FMVSS No. 305, such as the marking requirements. Therefore, the 
agency finds good cause to provide more time to comply with this final 
rule. The agency believes one year from the date of publication of the 
final rule is sufficient time for vehicle manufacturers to comply with 
the updated FMVSS No. 305 requirements. Therefore, the compliance date 
for the amendments in FMVSS No 305 is one year after publication of the 
final rule. We permit optional early compliance with this final rule.
    We note that in the ``DATES'' section at this beginning of this 
document NHTSA indicates that the ``effective date'' of this final rule 
is the date of publication of the rule. The ``effective date'' in the 
DATES section is the date the amendments should be incorporated into 
the CFR. That date is different from the ``compliance date'' discussed 
above. As stated above, NHTSA is permitting optional early compliance 
with this final rule. Because of this, we are amending 49 CFR 571.305 
(FMVSS No. 305) on the date of publication of this final rule so that 
interested manufacturers can begin certifying the compliance of their 
vehicles with the amended standard from that date.

V. Rulemaking Analyses and Notices

Executive Order 12866 and DOT Regulatory Policies and Procedures

    This rulemaking document was not reviewed by the Office of 
Management and Budget (OMB) under Executive Order (E.O.) 12866. It is 
not considered to be significant under E.O. 12866 or the Department's 
Regulatory Policies and Procedures. The amendments made by this final 
rule will have no significant effect on the national economy, as most 
of the requirements are already in voluntary industry standards and 
international standards that current electric powered vehicles 
presently meet.
    This final rule updates FMVSS No. 305 to incorporate the electrical 
safety requirements in GTR No. 13. This final rule also responds to 
petitions for rulemaking from Toyota and the Alliance to facilitate the 
introduction of fuel cell vehicles and 48-volt mild hybrid technologies 
into the vehicle fleet. The final rule adds electrical safety 
requirements in GTR No. 13 that involve electrical isolation and direct 
and indirect contact protection of high voltage sources to prevent 
electric shock during normal operation of electric powered vehicles. 
Today's final rule also provides an additional optional method of 
meeting post-crash electrical safety requirements that involve physical 
barriers of high voltage sources to prevent electric shock due to 
direct and indirect contact with live parts. Since there is widespread 
conformance with the requirements that would apply to existing 
vehicles, we anticipate no costs or benefits associated with this 
rulemaking.

Executive Order 13771

    Executive Order 13771 titled ``Reducing Regulation and Controlling 
Regulatory Costs,'' directs that, unless prohibited by law, whenever an 
executive department or agency publicly proposes for notice and comment 
or otherwise promulgates a new regulation, it shall identify at least 
two existing regulations to be repealed. In addition, any new 
incremental costs associated with new regulations shall, to the extent 
permitted by law, be offset by the elimination of existing costs. Only 
those rules deemed significant under section 3(f) of Executive Order 
12866, ``Regulatory Planning and Review,'' are subject to these 
requirements. As discussed above, this rule is not a significant rule 
under Executive Order 12866 and, accordingly, is not subject to the 
offset requirements of 13771.
    NHTSA has determined that this rulemaking is a deregulatory action 
under E.O. 13771, as it imposes no costs and, instead, amends FMVSS No. 
305 to give more flexibility to manufacturers not only to use modern 
electrical safety designs to produce electric vehicles, but also to 
introduce new technologies to the U.S. market, including hydrogen fuel 
cell vehicles and 48-volt mild hybrid technologies. Although NHTSA was 
not able to quantify any cost savings for this rule, in adopting an 
optional method of meeting post-crash electrical safety requirements 
involving use of physical barriers to prevent direct or indirect 
contact (by occupants, emergency services personnel and others) with 
high voltage sources, this final rule adjusts the standard to remove an 
obstruction that prevented HFCVs to be offered for sale in the U.S. Use 
of the physical barrier option will also enable manufacturers to 
produce 48-volt mild hybrid systems without having to use electrical 
isolation safety measures that involve more complexity, higher consumer 
costs, and higher mass, without an incremental safety benefit.

Regulatory Flexibility Act

    NHTSA has considered the effects of this final rule under the 
Regulatory Flexibility Act (5 U.S.C. 601 et seq., as amended by the 
Small Business Regulatory Enforcement Fairness Act (SBREFA) of 1996). I 
certify that this final rule will 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. 
Therefore, to the extent there is an economic impact on the 
manufacturers, it will only be minor.

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.

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.''
    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

[[Page 44959]]

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 \58\ addressing the same aspect of 
performance, not today's rulemaking, so consultation would be 
inappropriate.
---------------------------------------------------------------------------

    \58\ The issue of potential preemption of state tort law is 
addressed in the immediately following paragraph discussing implied 
preemption.
---------------------------------------------------------------------------

    Second, the Supreme Court has recognized the possibility, in some 
instances, of implied preemption of State requirements imposed on motor 
vehicle manufacturers, including sanctions imposed by State tort law. 
That possibility is dependent upon there being an actual conflict 
between a FMVSS and the State requirement. If and when such a conflict 
exists, the Supremacy Clause of the Constitution makes the State 
requirements unenforceable. See Geier v. American Honda Motor Co., 529 
U.S. 861 (2000), finding implied preemption of state tort law on the 
basis of a conflict discerned by the court,\59\ not on the basis of an 
intent to preempt asserted by the agency itself.
---------------------------------------------------------------------------

    \59\ The conflict was discerned based upon the nature (e.g., the 
language and structure of the regulatory text) and the safety-
related objectives of FMVSS requirements in question and the impact 
of the State requirements on those objectives.
---------------------------------------------------------------------------

    NHTSA has considered the nature (e.g., the language and structure 
of the regulatory text) and objectives of today's final rule and does 
not discern any existing State requirements that conflict with the rule 
or the potential for any future State requirements that might conflict 
with it. Without any conflict, there could not be any implied 
preemption of state law, including state tort law.

Executive Order 12988 (Civil Justice Reform)

    With respect to the review of the promulgation of a new regulation, 
section 3(b) of Executive Order 12988, ``Civil Justice Reform'' (61 FR 
4729; Feb. 7, 1996), requires that Executive agencies make every 
reasonable effort to ensure that the regulation: (1) Clearly specifies 
the preemptive effect; (2) clearly specifies the effect on existing 
Federal law or regulation; (3) provides a clear legal standard for 
affected conduct, while promoting simplification and burden reduction; 
(4) clearly specifies the retroactive effect, if any; (5) specifies 
whether administrative proceedings are to be required before parties 
file suit in court; (6) adequately defines key terms; and (7) addresses 
other important issues affecting clarity and general draftsmanship 
under any guidelines issued by the Attorney General. This document is 
consistent with that requirement.
    Pursuant to this Order, NHTSA notes as follows. The issue of 
preemption is discussed above. NHTSA notes further that there is no 
requirement that individuals submit a petition for reconsideration or 
pursue other administrative proceedings before they may file suit in 
court.

Privacy Act

    Please note that anyone can 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.

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 NPRM.

National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (NTTAA), Public Law 104-113, as amended by Public Law 107-
107 (15 U.S.C. 272), directs the agency to evaluate and use voluntary 
consensus standards in its regulatory activities unless doing so would 
be inconsistent with applicable law or is otherwise impractical. 
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) with 
explanations when the agency decides not to use available and 
applicable voluntary consensus standards. The NTTAA does not apply to 
symbols.
    FMVSS No. 305 has historically drawn largely from SAE J1766, and 
does so again for this current rulemaking, which updates FMVSS No. 305 
to facilitate the development of fuel cell and 48-volt mild hybrid 
technologies. It is based on GTR No. 13 and the latest version of SAE 
J1766 January 2014.

Unfunded Mandates Reform Act

    Section 202 of the Unfunded Mandates Reform Act of 1995 (UMRA), 
Pub. L. 104-4, requires Federal 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). Adjusting this amount by the 
implicit gross domestic product price deflator for the year 2013 
results in $142 million (106.733/75.324 = 1.42). This final rule will 
not result in a cost of $142 million or more to either State, local, or 
tribal governments, in the aggregate, or the private sector. Thus, this 
final rule is not subject to the requirements of sections 202 of the 
UMRA.

Executive Order 13609 (Promoting Regulatory Cooperation)

    The policy statement in section 1 of Executive Order 13609 
provides, in part: the regulatory approaches taken by foreign 
governments may differ from those taken by U.S. regulatory agencies to 
address similar issues. In some cases, the differences between the 
regulatory approaches of U.S. agencies and those of their foreign 
counterparts might not be necessary and might impair the ability of 
American businesses to export and compete internationally. In meeting 
shared challenges involving health, safety, labor, security, 
environmental, and other issues, international regulatory cooperation 
can identify approaches that are at least as protective as those that 
are or would be adopted in the absence of such cooperation. 
International regulatory cooperation can also reduce, eliminate, or 
prevent unnecessary differences in regulatory requirements.
    The agency participated in the development of GTR No. 13 to 
harmonize the standards of fuel cell vehicles. As a signatory member, 
NHTSA is obligated to initiate rulemaking to incorporate electrical 
safety requirements and options specified in GTR No. 13 into FMVSS No. 
305. The agency has initiated rulemaking by way of the March 10, 2016 
NPRM and completes it with this final rule.

Regulation Identifier Number

    The Department of Transportation assigns a regulation identifier 
number (RIN) to each regulatory action listed in

[[Page 44960]]

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.

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 write to us 
with your views.

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 1.95.

0
2. In Sec.  571.305:
0
a. Revise S1 and S2;
0
b. Under S4:
0
i. Add in alphabetical order definitions for ``Charge connector,'' 
``Connector,'' ``Direct contact,'' ``Electrical protection barrier,'' 
``Exposed conductive part,'' ``External electric power supply,'' and 
``Fuel cell system'';
0
ii. Revise the definitions of ``High voltage source'';
0
iii. Add in alphabetical order definitions for ``Indirect contact,'' 
``Live part,'' ``Luggage compartment,'' ``Passenger compartment,'' and 
``Possible active driving mode'';
0
iv. Revise the definition of ``Propulsion system''; and
0
v. Add in alphabetical order definitions for ``Protection degree 
IPXXB,'' ``Protection degree IPXXD,'' ``Service disconnect,'' and 
``Vehicle charge inlet'';
0
c. Revise S5.3 and S5.4; and
0
d. Add S5.4.1, S5.4.1.1, S5.4.1.1.1, S5.4.1.2, S5.4.1.3, S5.4.1.4, 
S5.4.1.5, S5.4.1.6, S5.4.2, S5.4.2.1, S5.4.2.2, S5.4.3, S5.4.3.1, 
S5.4.3.2, S5.4.3.3, S5.4.4, S5.4.5, S5.4.6, S5.4.6.1, S5.4.6.2, 
S5.4.6.3, S9, S9.1, S9.2, S9.3, and figures 6, 7a, 7b, and 8.
    The revisions and additions read 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 and retention of electric energy storage/
conversion devices during and after a crash, and protection from 
harmful electric shock during and after a crash and during normal 
vehicle operation.
    S2. Purpose. The purpose of this standard is to reduce deaths and 
injuries during and after a crash that occur because of electrolyte 
spillage from electric energy storage devices, intrusion of electric 
energy storage/conversion devices into the occupant compartment, and 
electrical shock, and to reduce deaths and injuries during normal 
vehicle operation that occur because of electric shock or driver error.
* * * * *
    S4. * * *
    Charge connector is a conductive device that, by insertion into a 
vehicle charge inlet, establishes an electrical connection of the 
vehicle to the external electric power supply for the purpose of 
transferring energy and exchanging information.
    Connector means a device providing mechanical connection and 
disconnection of high voltage electrical conductors to a suitable 
mating component, including its housing.
    Direct contact is the contact of persons with high voltage live 
parts.
* * * * *
    Electrical protection barrier is the part providing protection 
against direct contact with high voltage live parts from any direction 
of access.
    Exposed conductive part is the conductive part that can be touched 
under the provisions of the IPXXB protection degree and that is not 
normally energized, but that can become electrically energized under 
isolation fault conditions. This includes parts under a cover, if the 
cover can be removed without using tools.
    External electric power supply is a power supply external to the 
vehicle that provides electric power to charge the electric energy 
storage device in the vehicle through the charge connector.
    Fuel cell system is a system containing the fuel cell stack(s), air 
processing system, fuel flow control system, exhaust system, thermal 
management system, and water management system.
    High voltage source means any electric component which is contained 
in the electric power train or conductively connected to the electric 
power train and has a working voltage greater than 30 VAC or 60 VDC.
    Indirect contact is the contact of persons with exposed conductive 
parts.
    Live part is a conductive part of the vehicle that is electrically 
energized under normal vehicle operation.
    Luggage compartment is the space in the vehicle for luggage 
accommodation, separated from the passenger compartment by the front or 
rear bulkhead and bounded by a roof, hood or trunk lid, floor, and side 
walls, as well as by electrical protection barriers provided for 
protecting the occupants from direct contact with high voltage live 
parts.
    Passenger compartment is the space for occupant accommodation that 
is bounded by the roof, floor, side walls, doors, outside glazing, 
front bulkhead and rear bulkhead or rear gate, as well as electrical 
protection barriers provided for protecting the occupants from direct 
contact with high voltage live parts.
    Possible active driving mode is the vehicle mode when application 
of pressure to the accelerator pedal (or activation of an equivalent 
control) or release of the brake system causes the electric power train 
to move the vehicle.
    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, and electronic 
controllers.
    Protection degree IPXXB is protection from contact with high 
voltage live parts. It is tested by probing electrical protection 
barriers with the jointed test finger probe, IPXXB, in Figure 7b.
    Protection degree IPXXD is protection from contact with high 
voltage live parts. It is tested by probing electrical protection 
barriers with the test wire probe, IPXXD, in Figure 7a.
    Service disconnect is the device for deactivation of an electrical 
circuit when conducting checks and services of the vehicle electrical 
propulsion system.
* * * * *

[[Page 44961]]

    Vehicle charge inlet is the device on the electric vehicle into 
which the charge connector is inserted for the purpose of transferring 
energy and exchanging information from an external electric power 
supply.
* * * * *
    S5.3 Electrical safety. After each test specified in S6 of this 
standard, each high voltage source in a vehicle must meet one of the 
following requirements: electrical isolation requirements of 
subparagraph (a), the voltage level requirements of subparagraph (b), 
or the physical barrier protection requirements of subparagraph (c).
    (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) 100 ohms/volt for an AC high voltage source if it is 
conductively connected to a DC high voltage source, but only if the AC 
high voltage source meets the physical barrier protection requirements 
specified in S5.3(c)(1) and S5.3(c)(2); or
    (3) 100 ohms/volt for a DC high voltage source.
    (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.
    (c) Protection against electric shock by direct and indirect 
contact (physical barrier protection) shall be demonstrated by meeting 
the following three conditions:
    (1) The high voltage source (AC or DC) meets the protection degree 
IPXXB when tested according to the procedure specified in S9.1 using 
the IPXXB test probe shown in Figures 7a and 7b;
    (2) The resistance between exposed conductive parts of the 
electrical protection barrier of the high voltage source and the 
electrical chassis is less than 0.1 ohms when tested according to the 
procedures specified in S9.2. In addition, the resistance between an 
exposed conductive part of the electrical protection barrier of the 
high voltage source and any other simultaneously reachable exposed 
conductive parts of electrical protection barriers within 2.5 meters of 
it must be less than 0.2 ohms when tested using the test procedures 
specified in S9.2; and
    (3) The voltage between exposed conductive parts of the electrical 
protection barrier of the high voltage source and the electrical 
chassis is less than or equal to 30 VAC or 60 VDC as measured in 
accordance with S9.3. In addition, the voltage between an exposed 
conductive part of the electrical protection barrier of the high 
voltage source and any other simultaneously reachable exposed 
conductive parts of electrical protection barriers within 2.5 meters of 
it must be less than or equal to 30 VAC or 60 VDC as measured in 
accordance with S9.3.
    S5.4 Electrical safety during normal vehicle operation.
    S5.4.1 Protection against direct contact.
    S5.4.1.1 Marking. The symbol shown in Figure 6 shall be present on 
or near electric energy storage devices. The symbol in Figure 6 shall 
also be visible on electrical protection barriers which, when removed, 
expose live parts of high voltage sources. The symbol shall be yellow 
and the bordering and the arrow shall be black.
    S5.4.1.1.1 The marking is not required for electrical protection 
barriers that cannot be physically accessed, opened, or removed without 
the use of tools. Markings are not required for electrical connectors 
or the vehicle charge inlet.
    S5.4.1.2 High voltage cables. Cables for high voltage sources which 
are not located within electrical protection barriers shall be 
identified by having an outer covering with the color orange.
    S5.4.1.3 Service disconnect. For a service disconnect which can be 
opened, disassembled, or removed without tools, protection degree IPXXB 
shall be provided when tested under procedures specified in S9.1 using 
the IPXXB test probe shown in Figures 7a and 7b.
    S5.4.1.4 Protection degree of high voltage live parts.
    (a) Protection degree IPXXD shall be provided for high voltage live 
parts inside the passenger or luggage compartment when tested according 
to the procedures specified in S9.1 using the IPXXD test probe shown in 
Figure 7a.
    (b) Protection degree IPXXB shall be provided for high voltage live 
parts in areas other than the passenger or luggage compartment when 
tested according to the procedures specified in S9.1 using the IPXXB 
test probe shown in Figures 7a and 7b.
    S5.4.1.5 Connectors. Direct contact protection for a connector 
shall be provided by meeting the requirements specified in S5.4.1.4 
when the connector is connected to its corresponding mating component, 
and by meeting at least one of the requirements of subparagraphs (a), 
(b), or (c).
    (a) The connector meets the requirements of S5.4.1.4 when separated 
from its mating component, if the connector can be separated without 
the use of tools;
    (b) The voltage of the live parts becomes less than or equal to 60 
VDC or 30 VAC within one second after the connector is separated from 
its mating component; or,
    (c) The connector is provided with a locking mechanism (at least 
two distinct actions are needed to separate the connector from its 
mating component) and there are other components that must be removed 
in order to separate the connector from its mating component and these 
cannot be removed without the use of tools.
    S5.4.1.6 Vehicle charge inlet. Direct contact protection for a 
vehicle charge inlet shall be provided by meeting the requirements 
specified in S5.4.1.4 when the charge connector is connected to the 
vehicle inlet and by meeting at least one of the requirements of 
subparagraphs (a) or (b).
    (a) The vehicle charge inlet meets the requirements of S5.4.1.4 
when the charge connector is not connected to it; or
    (b) The voltage of the high voltage live parts becomes equal to or 
less than 60 VDC or equal to or less than 30 VAC within 1 second after 
the charge connector is separated from the vehicle charge inlet.
    S5.4.2 Protection against indirect contact.
    S5.4.2.1 The resistance between all exposed conductive parts of 
electrical protection barriers and the electrical chassis shall be less 
than 0.1 ohms when tested according to the procedures specified in 
S9.2.
    S5.4.2.2 The resistance between any two simultaneously reachable 
exposed conductive parts of the electrical protection barriers that are 
less than 2.5 meters from each other shall be less than 0.2 ohms when 
tested according to the procedures specified in S9.2.
    S5.4.3 Electrical isolation.
    S5.4.3.1 Electrical isolation of AC and DC high voltage sources. 
The electrical isolation of a high voltage source, determined in 
accordance with the procedure specified in S7.6 must be greater than or 
equal to one of the following:
    (a) 500 ohms/volt for an AC high voltage source;
    (b) 100 ohms/volt for an AC high voltage source if it is 
conductively connected to a DC high voltage source, but only if the AC 
high voltage source meets the requirements for protection against 
direct contact in S5.4.1.4 and the protection from indirect contact in 
S5.4.2; or

[[Page 44962]]

    (c) 100 ohms/volt for a DC high voltage source.
    S5.4.3.2 Exclusion of high voltage sources from electrical 
isolation requirements. A high voltage source that is conductively 
connected to an electric component which is conductively connected to 
the electrical chassis and has a working voltage less than or equal to 
60 VDC, is not required to meet the electrical isolation requirements 
in S5.4.3.1 if the voltage between the high voltage source and the 
electrical chassis is less than or equal to 30 VAC or 60 VDC.
    S5.4.3.3 Electrical isolation of high voltage sources for charging 
the electric energy storage device. For the vehicle charge inlet 
intended to be conductively connected to the AC external electric power 
supply, the electric isolation between the electrical chassis and the 
high voltage sources that are conductively connected to the vehicle 
charge inlet during charging of the electric energy storage device 
shall be greater than or equal to 500 ohms/volt when the charge 
connector is disconnected. The electrical isolation is measured at the 
high voltage live parts of the vehicle charge inlet and determined in 
accordance with the procedure specified in S7.6. During the 
measurement, the rechargeable electric energy storage system may be 
disconnected.
    S5.4.4 Electrical isolation monitoring. DC high voltage sources of 
vehicles with a fuel cell system 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.
    S5.4.5 Electric shock protection during charging. For motor 
vehicles with an electric energy storage device that can be charged 
through a conductive connection with a grounded external electric power 
supply, a device to enable conductive connection of the electrical 
chassis to the earth ground shall be provided. This device shall enable 
connection to the earth ground before exterior voltage is applied to 
the vehicle and retain the connection until after the exterior voltage 
is removed from the vehicle.
    S5.4.6 Mitigating driver error.
    S5.4.6.1 Indicator of possible active driving mode. At least a 
momentary indication shall be given to the driver each time the vehicle 
is first placed in possible active driving mode after manual activation 
of the propulsion system. This requirement does not apply under 
conditions where an internal combustion engine provides directly or 
indirectly the vehicle's propulsion power when the vehicle is first 
placed in a possible active driving mode after manual activation of the 
propulsion system.
    S5.4.6.2 Indicator of possible active driving mode when leaving the 
vehicle. When leaving the vehicle, the driver shall be informed by an 
audible or visual signal if the vehicle is still in the possible active 
driving mode.
    S5.4.6.3 Prevent drive-away. If the on-board electric energy 
storage device can be externally charged, vehicle movement of more than 
150 mm by its own propulsion system shall not be possible as long as 
the charge connector of the external electric power supply is 
physically connected to the vehicle charge inlet in a manner that would 
permit charging of the electric energy storage device.
* * * * *
    S9 Test methods for physical barrier protection from electric shock 
due to direct and indirect contact with high voltage sources.
    S9.1 Test method to evaluate protection from direct contact with 
high voltage sources.
    (a) Any parts surrounding the high voltage components are opened, 
disassembled, or removed without the use of tools.
    (b) The selected access probe is inserted into any gaps or openings 
of the electrical protection barrier with a test force of 10 N  1 N with the IPXXB probe or 1 to 2 N with the IPXXD probe. If 
the probe partly or fully penetrates into the electrical protection 
barrier, it is placed in every possible position to evaluate contact 
with high voltage live parts. If partial or full penetration into the 
electrical protection barrier occurs with the IPXXB probe, the IPXXB 
probe shall be placed as follows: starting from the straight position, 
both joints of the test finger are rotated progressively through an 
angle of up to 90 degrees with respect to the axis of the adjoining 
section of the test finger and are placed in every possible position.
    (c) A low voltage supply (of not less than 40 V and not more than 
50 V) in series with a suitable lamp may be connected between the 
access probe and any high voltage live parts inside the electrical 
protection barrier to indicate whether high voltage live parts were 
contacted.
    (d) A mirror or fiberscope may be used to inspect whether the 
access probe touches high voltage live parts inside the electrical 
protection barrier.
    (e) Protection degree IPXXD or IPXXB is verified when the following 
conditions are met:
    (i) The access probe does not touch high voltage live parts. The 
IPXXB access probe may be manipulated as specified in S9.1(b) for 
evaluating contact with high voltage live parts. The methods specified 
in S9.1(c) or S9.1(d) may be used to aid the evaluation. If method 
S9.1(c) is used for verifying protection degree IPXXB or IPXXD, the 
lamp shall not light up.
    (ii) The stop face of the access probe does not fully penetrate 
into the electrical protection barrier.
    S9.2 Test method to evaluate protection against indirect contact 
with high voltage sources. At the option of the manufacturer, 
protection against indirect contact with high voltage sources shall be 
determined using the test method in subparagraph (a) or subparagraph 
(b).
    (a) Test method using a resistance tester. The resistance tester is 
connected to the measuring points (the electrical chassis and any 
exposed conductive part of electrical protection barriers or any two 
simultaneously reachable exposed conductive parts of electrical 
protection barriers that are less than 2.5 meters from each other), and 
the resistance is measured using a resistance tester that can measure 
current levels of at least 0.2 Amperes with a resolution of 0.01 ohms 
or less. The resistance between two exposed conductive parts of 
electrical protection barriers that are less than 2.5 meters from each 
other may be calculated using the separately measured resistances of 
the relevant parts of the electric path.
    (b) Test method using a DC power supply, voltmeter and ammeter.
    (1) Connect the DC power supply, voltmeter and ammeter to the 
measuring points (the electrical chassis and any exposed conductive 
part or any two simultaneously reachable exposed conductive parts that 
are less than 2.5 meters from each other) as shown in Figure 8.
    (2) Adjust the voltage of the DC power supply so that the current 
flow becomes more than 0.2 Amperes.
    (3) Measure the current I and the voltage V shown in Figure 8.
    (4) Calculate the resistance R according to the formula, R=V/I.
    (5) The resistance between two simultaneously reachable exposed 
conductive parts of electrical protection barriers that are less than 
2.5 meters from each other may be calculated using the separately 
measured resistances of the relevant parts of the electric path.
    S9.3 Test method to determine voltage between exposed conductive 
parts of electrical protection barriers and the electrical chassis and 
between

[[Page 44963]]

exposed conductive parts of electrical protection barriers.
    (a) Connect the voltmeter to the measuring points (exposed 
conductive part of an electrical protection barrier and the electrical 
chassis or any two simultaneously reachable exposed conductive parts of 
electrical protection barriers that are less than 2.5 meters from each 
other).
    (b) Measure the voltage.
    (c) The voltage between two simultaneously reachable exposed 
conductive parts of electrical protection barriers that are less than 
2.5 meters from each other may be calculated using the separately 
measured voltages between the relevant electrical protection barriers 
and the electrical chassis.
* * * * *
BILLING CODE 4910-59-P
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Jack Danielson,
Acting Deputy Administrator.
[FR Doc. 2017-20350 Filed 9-26-17; 8:45 am]
BILLING CODE 4910-59-C


Current View
CategoryRegulatory Information
CollectionFederal Register
sudoc ClassAE 2.7:
GS 4.107:
AE 2.106:
PublisherOffice of the Federal Register, National Archives and Records Administration
SectionRules and Regulations
ActionFinal rule.
DatesEffective date: This final rule is effective September 27, 2017.
ContactFor technical issues, you may call William J. S[aacute]nchez, Office of Crashworthiness Standards (telephone: 202-493-0248) (fax: 202-493-2990). For legal issues, you may call Deirdre Fujita, Office of Chief Counsel (telephone: 202-366-
FR Citation82 FR 44945 
RIN Number2127-AL68
CFR AssociatedImports; Motor Vehicles and Motor Vehicle Safety

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