Federal Motor Vehicle Safety Standards

DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. NHTSA-98-4515]

RIN 2127-AF43

Federal Motor Vehicle Safety Standards

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

ACTION: Notice of proposed rulemaking.

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

SUMMARY: This document proposes a new Federal motor vehicle safety

standard that would establish requirements and test procedures which

address safety issues exclusive to electric vehicles: Electrolyte

spillage, post-crash retention of batteries in their mounts, and shock

hazard. The standard would be based upon SAE J1766 FEB96 ``Recommended

Practice for Electric and Hybrid Electric Vehicle Battery Systems Crash

Integrity Testing,'' and be known as Standard No. 305, ``Electric-

powered vehicles: electrolyte spillage and

[[Page 54653]]

electrical shock protection.'' Test procedures would include the

frontal barrier crash test of Standard No. 208, the side moving barrier

crash test of Standard No. 214, and the rollover and rear moving

barrier crash tests of Standard No. 301. However, as proposed, the

standard would not apply to low-speed electric vehicles regulated by

Standard No. 500, and the agency is asking for comment on this issue.

DATES: Comments are due November 27, 1998.

ADDRESSES: Comments should refer to the docket number and be submitted

to Docket Management, PL-401, 400 Seventh St., SW, Washington, DC

20590. Docket hours are from 10 a.m. to 4 p.m.

FOR FURTHER INFORMATION CONTACT: Charles Hott, Office of Safety

Performance Standards, NHTSA (202-366-0427).

SUPPLEMENTARY INFORMATION:

Background

The 1990s may be remembered as the beginning of a new generation of

electric vehicles. In mid-decade, General Motors Corporation (GM)

introduced the EV1, an electric-powered passenger car, offered for

lease in selected western markets in the United States. Other

manufacturers, such as Honda and Nissan, have also introduced new

electric vehicles (EVs). The primary impetus for the introduction of

EVs into the marketplace appears to be the Clean Air Act Amendments of

1990 which included provisions for zero emission vehicles (ZEV). EVs

are the only known vehicles that will meet the emission requirements

for ZEVs. In California, these provisions were to become effective

beginning in model year 1998, and would have required automobile

manufacturers to sell, collectively, 40,000 EVs in the model year.

However, those provisions were delayed by the California Air Resources

Board until model year 2003. At that time, car companies will be

required to meet 10 percent of their sales with ZEVs. In addition, the

Energy Policy Act of 1992 requires Federal and State fleets to acquire

increasing percentages of alternative fueled vehicles.

On December 27, 1991, NHTSA published an advance notice of proposed

rulemaking (ANPRM) on EV safety (56 FR 67038). The purpose of that

notice was to help the agency determine what existing Federal motor

vehicle safety standards (FMVSS) may need modification to better

accommodate the unique technology of EVs and what new FMVSS may need to

be written to assure their safe introduction. The ANPRM requested

comments on a broad range of potential EV safety issues including

battery electrolyte spillage and electric shock hazard. The ANPRM

elicited widespread public interest and 46 comments were received.

After reviewing the comments and information received in response

to the ANPRM, NHTSA concluded in a November 18, 1992 notice (57 FR

54354) that it was premature to initiate rulemaking for FMVSS specific

for EVs. In that notice the agency stated that further research was

needed in the areas of battery electrolyte spillage and electric shock

hazard.

Shortly thereafter, in 1993, NHTSA conducted research and testing

on two converted EVs. These vehicles were tested as specified in FMVSS

No. 208, ``Occupant Crash Protection.'' Both vehicles were equipped

with flooded (i.e., filled with liquid electrolyte) lead-acid batteries

located in the engine and luggage compartments in the front and rear of

the vehicle. One vehicle was equipped with twelve 12-volt batteries

(five in the front and seven in the rear). The other vehicle was

equipped with ten 12-volt batteries (four in the front and six in the

rear). Both vehicles were subjected to 48 km/h frontal crashes into a

fixed barrier. In both cases the front batteries sustained significant

damage, spilling large quantities of electrolyte. On one vehicle, 17.7

liters of electrolyte spilled from the front batteries as a result of

the crash and in the other vehicle, 10.4 liters. In addition,

electrical arcs were observed under the hood of one vehicle during the

crash.

The following year, NHTSA published a notice of request for

comments (59 FR 49901, September 30, 1994 ) to help it to assess the

need to regulate battery electrolyte spillage and electric shock hazard

of EVs during a crash or rollover. Thirty-two comments were received

from automobile manufacturers, EV converters, and industry

associations. The majority of the commenters supported some type of

Federal regulation for electrolyte spillage and electric shock

prevention, provided that the requirements of the regulation were

performance based and not design restrictive to the extent that they

might inhibit technology development. Two manufacturers, Ford Motor

Company (Ford) and Nissan, and two industry associations (Electric

Vehicle Industry Association and Electric Vehicles of America) did not

believe that Federal regulation was necessary because electric vehicle

design was constantly changing due to technological breakthroughs.

However, Ford did state that it would follow the recommendation of

industry associations such as the Society of Automotive Engineers (SAE)

when SAE J1766 ``Recommended Practice For Electric and Hybrid Electric

Vehicle Battery Systems Crash Integrity Testing'' was finally

developed.

In 1995, NHTSA again conducted research and testing, this time on

four EVs. Three vehicles were converted to run on electricity and one

was built as an EV. The three converted vehicles were equipped with

starved (i.e., electrolyte that is absorbed in an inert material to

prevent leakage in case of rupture) lead-acid batteries and the vehicle

built as an EV was equipped with flooded lead-acid batteries. Three

vehicles were subjected to 48 km/h frontal crashes similar to the test

described in FMVSS No. 208, ``Occupant Crash Protection'' and one was

subjected to a 54 km/h side crash similar to the test specified in

FMVSS No. 214,'' Side Impact Protection.'' Each vehicle was subjected

to pre- and post-crash rollover tests to measure electrolyte spillage.

The crash and rollover tests revealed that the vehicles with the

starved lead-acid batteries had very little leakage (as expected

because of their design), while the vehicle with the flooded lead-acid

batteries leaked approximately 50 liters of electrolyte. Electrical

isolation tests were also performed on these vehicles before and after

each of the crash tests. Two of the converted EVs maintained their

electrical isolation after the crash tests. One of the converted EVs

was subjected to a side impact test. That EV chafed a wire which came

in contact with the vehicle structure during the crash and did not

maintain electrical isolation. The vehicle built as an EV was subjected

to a frontal crash test. That vehicle lost electrical isolation when

two of the battery connectors came in contact with the battery tunnel

during the crash.

SAE J1766 ``Recommended Practice for Electric and Hybrid Electric

Vehicle Battery Systems Crash Integrity Testing''

During NHTSA's earlier rulemaking activities, there was not yet an

industry standard in place that addressed potential safety problems in

EVs. Following circulation of drafts in the years previous, in February

1996, SAE published its Recommended Practice SAE J1766 ``Recommended

Practice for Electric and Hybrid Electric Vehicle Battery Systems Crash

Integrity Testing.'' As it notes, electric and hybrid electric vehicles

contain many types of battery systems. J1766 deems adequate

[[Page 54654]]

barriers between occupants and battery systems necessary to provide

protection from potentially harmful factors and materials within the

battery system, which can cause injury to vehicle occupants during

different crash scenarios.

The potentially harmful factors and materials include:

electrical isolation integrity, electrolyte spillage and liquid

interactions, and retention of the battery system. Maintaining

electrical isolation of the system is important to prevent hazardous

shock of vehicle occupants. Electrolyte spillage and battery fluid

interactions should be minimized to prevent chemical reactions and

electrical conductance. The latter could lead to an electrical shock

hazard.

The purpose of SAE J1766 is to define minimum performance standards

and establish test methods which evaluate battery system spillage,

retention, electrical system isolation, and liquid interaction in

electric and hybrid electric vehicles during crash scenarios. The

Recommended Practice covers all electric and hybrid electric vehicles

with a GVWR of 4536 kg (10,000 lbs) or less.

SAE J1766 establishes certain performance criteria when an EV is

subjected to the frontal impact procedures of FMVSS No. 208 (including

the 30-degree offsets), the side impact procedures of FMVSS 214, and

the rear impact procedure of FMVSS No. 301. No spillage of electrolyte

into the occupant compartment is permitted. Outside the passenger

compartment, electrolyte spillage is limited to 5 liters for a 30-

minute period after vehicle motion ceases and throughout the post crash

rollover test. Battery modules must stay restrained in the vehicle,

without any component intruding into the occupant compartment.

Electrical isolation between the chassis and high voltage system is at

least 500 ohms per nominal volt.

Proposed Motor Vehicle Safety Standard No. 305

NHTSA is proposing that similar provisions be adopted in a new

FMVSS No. 305 to afford the public protection from electrolyte spillage

and electric shock hazards in crashes. The provisions are based upon

those of SAE J1766 and should help ensure the safe introduction of new

EVs into the marketplace.

FMVSS No. 305 would apply to all passenger cars, and to

multipurpose passenger vehicles, trucks, and buses with a GVWR of 4536

kg or less, and to school buses with a GVWR over 4536 kg, that use more

than 72 volts of electricity as propulsion power. This GVWR is the

equivalent of 10,000 pounds. Seventy-two volts is the equivalent of six

12-volt batteries. The standard would apply to EVs with a maximum speed

of more than 40 kilometers per hour, that is, greater than 25 miles per

hour. The agency notes that it has recently issued a standard expressly

for low-speed vehicles (LSVs), FMVSS No. 500 (63 FR 33194; June 17,

1998). LSVs are any 4-wheeled vehicles, other than trucks, with a

maximum speed of not less than 32 kilometers per hour nor more than 40

kilometers per hour. EVs subject to the rule could include Neighborhood

Electric Vehicles (NEVs) and those battery-powered golf cars within the

speed range. FMVSS No. 500 does not require LSVs to meet FMVSS Nos.

208, 214, and 301, which contain some 48 and 54 kilometers per hour

impact barrier tests proposed for FMVSS No. 305.

Under proposed FMVSS No. 305, EVs covered by the standard, other

than heavy school buses, would be required to meet leakage and battery

retention requirements that are essentially those of SAE J1766 after

front (FMVSS No. 208), side (FMVSS No.214), and rear impact barrier

crash tests (FMVSS No. 301). A static rollover test (FMVSS No. 301)

would also be conducted both before and after each of these crash

tests. Heavy school buses (those with a GVWR over 4536 kg) would be

required to meet the same performance requirements after a moving

contour barrier frontal crash test, without the pre- and post-test

rollovers. The performance requirements proposed are that there shall

be no electrolyte spillage in the passenger compartment, with spillage

outside the compartment limited to 5 liters total in a 30-minute period

following the cessation of motion after a crash test. Intrusion of the

battery system components into the occupant compartment would also be

prohibited. Batteries must be restrained in the vehicle in their

original installations. The electric isolation value must be at least

500 ohms per nominal volt, as determined by the SAE procedure for the

measurement of the insulation resistance of the propulsion battery of

an EV. The standard known resistance Ro (in ohms) should be

approximately 500 times the nominal operating voltage of the vehicle

(in volts). The Ro is not required to be precisely this value since the

equations are valid for any Ro; however, a Ro value in this range

should provide good resolution for the voltage measurements.

Specific Issues for Which NHTSA Seeks Comment

1. Costs to conform. Commenters are asked to inform NHTSA the

extent to which, if any, the proposed rule would impose costs on

manufacturers of EVs to meet electrolyte spillage, battery retention,

and electrical isolation test requirements.

2. Adequacy of spillage specification. The proposed limit of 5.0

liters, contained in SAE J1766, is based upon the amount of electrolyte

that is contained in present large automotive batteries. Commenters are

asked for views on whether a different amount may be more appropriate

to protect the public in EV crashes.

3. Adequacy of electrical isolation specification. The agency is

interested in commenters' views on the NHTSA/SAE electrical isolation

specification of 500 ohms/volt. The SAE adopted this requirement

because the sensation threshold for most humans is around 2

milliamperes and the head-to-foot resistance is about 500 ohms. This is

the value at which most humans will feel a slight sensation from

electrical current. NHTSA understands that the European community is

looking at a similar requirement.

4. Coverage of proposed FMVSS No. 305. The proposed standard would

not apply to vehicles that use less than 72 volts of electricity as

propulsion power. NHTSA is aware that two LSVs will be produced with

six 12-volt batteries totaling 72 volts, the Bombardier NV and the GEM

vehicle (the Trans2 NEV design upgraded from 48 volts), and, it has

tentatively decided to exclude LSVs from the final rule. However, there

may be vehicles or vehicle designs whose maximum speed exceeds 40

kilometers per hour but which are powered, in whole or in part (perhaps

a hybrid electric configuration), by less than 72 volts of electricity.

NHTSA is interested in learning if there are any such vehicles or

vehicle designs and whether it would be appropriate to apply FMVSS No.

305 to them. NHTSA notes that its LSV definition excludes trucks and

asks whether those that are powered by less than 72 volts of

electricity should be covered.

5. Whether proposed FMVSS No. 305 should apply to electric LSVs.

Proposed Standard No. 305 would not apply to LSVs, i.e., passenger-

carrying EVs with a maximum speed between 32 and 40 kilometers per

hour. It is anticipated that a substantial portion of LSVs may be

electric vehicles. NHTSA seeks the views of commenters on whether

proposed FMVSS No. 305 should apply to LSVs, and, if so, whether the

[[Page 54655]]

proposed requirements are reasonable, practicable, and appropriate for

LSVs. The tests proposed are intended to limit electrolyte spillage,

battery intrusion, and shock hazard. Commenters should address each of

these requirements as they might be modified to apply to electric LSVs.

6. Rollover test. The SAE currently recommends that the vehicle

undergo a rollover test before the barrier impact test. NHTSA is

concerned that damage may occur to the test vehicle during rollover

that could affect the results of the barrier impact test. Accordingly,

comments are requested as to whether there should be a rollover test

before the barrier impact test and as to the importance of conducting a

rollover test before the barrier impact test.

Proposed Effective Date

NHTSA believes that an effective date of one year after the

issuance of the final rule should be sufficient for manufacturers

covered by FMVSS No. 305 to comply with the proposed new safety

standard. The major EV manufacturers all are using, or plan to use,

battery types that are not susceptible to leaking large amounts of

electrolytes and, to NHTSA's knowledge, all incorporate a device that

would shut-off the propulsion battery current or prevent loss of

electrical isolation in the event of a crash or short circuit.

Request for Comments

Interested persons are invited to submit comments on the proposal.

It is requested but not required that 10 copies be submitted.

All comments must not exceed 15 pages in length (49 CFR 553.21).

Necessary attachments may be appended to these submissions without

regard to the 15-page limit. This limitation is intended to encourage

commenters to detail their primary arguments in a concise fashion.

If a commenter wishes to submit certain information under a claim

of confidentiality, three copies of the complete submission, including

purportedly confidential business information, should be submitted to

the Chief Counsel, NHTSA, at the street address given above, and seven

copies from which the purportedly confidential information has been

deleted should be submitted to the Docket Section. A request for

confidentiality should be accompanied by a cover letter setting for the

information specified in the agency's confidential business information

regulation, 49 CFR part 512.

All comments received before the close of business on the comment

closing date indicated above for the proposal will be considered, and

will be available for examination in the docket at the above address

both before and after that date. To the extent possible, comments filed

after the closing date will also be considered. Comments received too

late for consideration in regard to the final rule will be considered

as suggestions for further rulemaking action. Comments on the proposal

will be available to inspection in the docket. NHTSA will continue to

file relevant information as it becomes available in the docket after

the closing date and it is recommended that interested persons continue

to examine the docket for new material.

Those persons desiring to be notified upon receipt of their

comments in the rules docket should enclose a self-addressed stamped

postcard in the envelope with their comments. Upon receiving the

comments, the docket supervisor will return the postcard by mail.

Rulemaking Analyses

Executive Order 12866 and DOT Regulatory Policies and Procedures

The Office of Management and Budget has not reviewed this

rulemaking action under Executive Order 12866. It has been determined

that the rulemaking action is not significant under Department of

Transportation regulatory policies and procedures. Informal discussions

with some EV manufacturers indicate that the industry is aware of SAE

J1766 and that manufacturers are planning or producing EVs with

batteries designed for minimal leakage, and to shut off the current or

prevent loss of electrical isolation in the event of a crash. The added

costs of the proposed tests should be minimal, and the agency has asked

for comments on this issue to verify its assumption. The tests of FMVSS

No. 305 can be conducted as part of the FMVSS No. 208 and No. 214

certification tests, as well as the FMVSS No. 301 rollover tests if the

vehicle is a hybrid fueled in part by gasoline, or contains a heater

fueled by gasoline. The impacts of the proposed rule are believed to be

so minimal as not to warrant preparation of a full regulatory

evaluation.

Regulatory Flexibility Act

The agency has also considered the impacts of this rulemaking

action in relation to the Regulatory Flexibility Act (5 U.S.C. 601 et

seq. I certify that this rulemaking action will not have a significant

economic impact upon a substantial number of small entities.

The following is NHTSA's statement providing the factual basis for

the certification (5 U.S.C. 605(b)). The technology to prevent leakage

of electrolytes, battery retention, and electrical isolation in the

event of the crash of a battery-powered motor vehicle is simple and has

been well known for years. The specifications of the industry standard,

J1766, have been settled since February 1996. The agency believes that

a substantial portion of the nascent EV industry is already designing

its production to comport with SAE J1766. Verification of compliance

with proposed FMVSS No. 305 can be determined at the same time an EV is

tested for compliance with FMVSS Nos. 208 and 214 and the cost of

testing to these standards should be minimally impacted. However, there

would be an additional cost imposed by conducting a static rollover

test in conjunction with each of these standards, as they are not

otherwise required. Moreover, if an EV is not otherwise required to

comply with FMVSS No. 301, there would be the added cost of a rear

moving barrier impact test if the EV manufacturer chooses to certify

its vehicle on the basis of an actual test rather than on engineering

studies, computer simulations, mathematical calculations, or other

means. Since the overall economic impact is not believed to be

significant, the agency has not determined formally whether the

entities affected by the rules are ``small businesses'' within the

meaning of the Regulatory Flexibility Act. In NHTSA's experience,

manufacturers of motor vehicles are generally not ``small businesses.''

Accordingly, no regulatory flexibility analysis has been prepared.

Executive Order 12612 (Federalism)

This action has been analyzed in accordance with the principles and

criteria contained in Executive Order 12612 on ``Federalism.'' It has

been determined that the rulemaking action does not have sufficient

federalism implications to warrant the preparation of a Federalism

Assessment.

National Environmental Policy Act

NHTSA has analyzed this rulemaking action for purposes of the

National Environmental Policy Act. The rulemaking action would not have

a significant effect upon the environment as it does not affect the

present method of manufacturing motor vehicle lighting equipment.

Civil Justice Reform

This rule will not have any retroactive effect. Under 49 U.S.C.

30103(b)(1),

[[Page 54656]]

whenever a Federal motor vehicle safety standard is in effect, a state

may not adopt or maintain a safety standard applicable to the same

aspect of performance which is not identical to the Federal standard.

Section 30161 sets forth a procedure for judicial review of final rules

establishing, amending, or revoking Federal motor vehicle safety

standards. That section does not require submission of a petition for

reconsideration or other administrative proceedings before parties may

file suit in court.

Unfunded Mandates Reform Act of 1995

The Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4) requires

agencies to prepare a written assessment of the cost, 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. Because this proposed rule would not have a $100

million effect, no Unfunded Mandates assessment has been prepared.

List of Subjects in 49 CFR Part 571

Imports, Motor vehicle safety, Motor vehicles, Reporting and

recordkeeping requirements

PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS

In consideration of the foregoing, 49 CFR part 571 would be amended

as follows:

1. The authority citation for part 571 would continue to read as

follows:

Authority: 49 U.S.C. 322, 30111, 30115, 30166; delegation of

authority at 49 CFR 1.50.

2. A new Sec. 571.305 would be added to subpart B to read as set

forth below:

Sec. 571.305 Standard No. 305; Electric-powered vehicle: electrolyte

spillage and electrical shock protection.

S1. Scope. This standard specifies requirements for limitation of

electrolyte spillage, retention of propulsion batteries after a crash,

and electrical isolation of the chassis from ionic conductance to the

high-voltage system, to be met by vehicles that use electricity as

propulsion power.

S2. Purpose. The purpose of this standard is to reduce deaths and

injuries during a crash which occur because of electrolyte spillage

from propulsion batteries, intrusion of propulsion battery system

components into the occupant compartment, and electrical shock.

S3. Application. This standard applies to passenger cars, and to

multipurpose passenger vehicles, trucks and buses (other than school

buses) with a GVWR 4536 kg or less, that use more than 72 volts of

electricity as propulsion power and whose speed attainable in 1.6 km is

more than 40 km/h, on a paved level surface. This standard also applies

to all school buses that use electricity as propulsion power.

S4. Definition.

Battery system component means any part of a battery module,

interconnect, venting system, battery restraint device, and battery box

or container which holds the individual battery modules.

S5. General requirements. Except for a school bus with a GVWR that

is greater than 4536 kg , each vehicle to which this standard applies,

when tested according to S6 under the conditions of S7, shall meet the

requirements of S5.1, S5.2, and S5.3. Each school bus with a GVWR that

is greater than 4536 kg , when tested according to S6.6 under the

conditions of S7, shall meet the requirements of S5.1, S5.2, and S5.3.

S5.1 Electrolyte spillage from propulsion batteries. There shall

be no spillage of electrolyte from propulsion batteries into the

passenger compartment. Not more than 5.0 liters of electrolyte from

propulsion batteries shall leak outside the passenger compartment.

Spillage and leakage are measured from the time the vehicle ceases

motion after a crash until 30 minutes thereafter, and throughout any

static rollover, either before or after a crash test.

S5.2 Battery retention. Battery modules shall remain restrained in

the location in which they are installed in the vehicle. No part of any

battery system component shall enter the passenger compartment, as

determined by a visual inspection.

S5.3 Electrical isolation. Electrical isolation between the

battery system and the vehicle electricity-conducting structure shall

be maintained at a minimum of 500 ohm/volt.

S6. Test requirements. Except for a school bus with a GVWR greater

than 4536 kg, each vehicle to which this standard applies shall be

capable of meeting the requirements of any applicable static rollover/

barrier crash/static rollover test sequence, without alteration of the

vehicle during the test sequence. A particular vehicle need not meet

further test requirements after having been subjected to a single

static rollover/barrier crash/static rollover test sequence.

S6.1 Pre-crash test static rollover. The vehicle shall meet the

requirements of S5.1, S5.2, and S5.3, after being rotated on its

longitudinal axis to each successive increment of 90 degrees before

each crash test specified in S6.2, S6.3, and S6.4.

S6.2 Frontal barrier crash. After a static rollover, when the

vehicle traveling longitudinally forward at any speed, up to and

including 48 km/h impacts a fixed collision barrier that is

perpendicular to the line of travel of the vehicle, or at any angle up

to 30 degrees in either direction from the perpendicular to the line of

travel of the vehicle, with the 50th percentile male test dummies as

specified in part 572 of this chapter at each front outboard designated

position and at any other position whose protection system is required

to be tested by a dummy under the provisions of Standard No. 208, under

the applicable conditions of S7, the vehicle shall meet the

requirements of S5.1, S5.2, and S5.3.

S6.3 Rear moving barrier crash. After a static rollover, when the

vehicle is impacted from the rear by a barrier moving at 48 km/h with

50th percentile male test dummies as specified in part 572 of this

chapter at each front outboard designated seating position, under the

applicable conditions of S7, the vehicle shall meet the requirements of

S5.1, S5.2, and S5.3.

S6.4 Side impact moving deformable barrier crash. After a static

rollover, when the vehicle is impacted from the side by a deformable

barrier moving at 54 km/h, the vehicle shall meet the requirements of

S5.1, S5.2, and S5.3.

S6.5 Post-crash test static rollover. The vehicle shall meet the

requirements of S5.1, S5.2, and S5.3, after being rotated on its

longitudinal axis to each successive increment of 90 degrees after each

crash test specified in S6.2, S6.3, and S6.4.

S6.6 Moving contoured barrier crash for school buses with a GVWR

greater than 4536 kg. When a moving contoured barrier assembly is

traveling longitudinally forward at any speed up to and including 48

km/h and impacts a school bus with a GVWR greater than 4536 kg at any

point and any angle, the school bus shall meet the requirements of

S5.1, S5.2, and S5.3.

S7. Test conditions. When the vehicle is tested according to S6,

the requirements of S5 shall be met under the following conditions.

Where a range is specified, the vehicle must be capable of meeting the

requirements at all points within the range.

S7.1 Battery state of charge. The battery system is charged using

the vehicle manufacturer's recommended charging system. All tests are

performed with the propulsion batteries charged to not less than 95

percent capacity.

S7.2 Vehicle conditions. The switch or device that provides power

from the propulsion batteries to the propulsion motor(s) is in the

activated position or the ready to drive position.

S7.2.1 The parking brake is disengaged and the transmission, if

any, is in the neutral position. In a test conducted under S6.6, the

parking brake is set.

[[Page 54657]]

S7.2.2 Tires are inflated to the manufacturer's specifications.

S7.2.3 The vehicle, including test devices and instrumentation, is

loaded as follows:

(a) A passenger car is loaded to its unloaded vehicle weight plus

its rated cargo and luggage capacity weight, secured in the luggage

area, plus the necessary test dummies as specified in S6, restrained

only by means that are installed in the vehicle for protection at its

seating position.

(b) A multipurpose passenger vehicle, truck, or bus with a GVWR of

4536 kg or less is loaded to its unloaded vehicle weight plus the

necessary test dummies, as specified in S6., plus 136 kg or its rated

cargo and luggage capacity weight, whichever is less. Each dummy shall

be restrained only by means that are installed in the vehicle for

protection at its seating position.

(c) A school bus with a GVWR greater than 4536 kg is loaded to its

unloaded vehicle weight plus 54.4 kg at each designated seating

position.

S7.3 Static rollover test conditions. In addition to the

conditions of S7.1 and S7.2, the conditions of S7.4 of Sec. 571.301

apply to the conduct of static rollover tests specified in S6.1 and

S6.5.

S7.4 Rear moving barrier crash test conditions. In addition to the

conditions of S7.1 and S7.2, the conditions of S7.3 of Sec. 571.301

apply to the conduct of the rear moving barrier crash test specified in

S6.3. The rear moving barrier is described in S8.2 of Sec. 571.208 and

diagramed in Figure 1 of Sec. 571.301.

S7.5 Side impact moving deformable barrier crash test conditions.

In addition to the conditions of S7.1 and S7.2, the conditions of

S6.10, S6.11, and S6.12 of Sec. 571.214 apply to the conduct of the

side impact moving deformable barrier crash specified in S6.4.

S7.6 Moving contoured barrier crash. In addition to the conditions

of S7.1 and S7.2, the conditions of S7.5 of Sec. 571.301 apply to the

conduct of the moving contoured barrier crash test specified in S6.6.

S7.7 Electrical isolation test procedure. In addition to the

conditions of S7.1 and S7.2, the following conditions apply to the

measurement of electrical isolation specified in S5.3.

S7.7.1 The propulsion battery system is connected to the vehicle's

propulsion system, and the vehicle ignition is in the ``on'' (traction

(propulsion) system energized) position.

S7.7.2 The voltmeter used in this test measures direct current

values and has an internal resistance of at least 10 M.

S7.7.3 The voltage is measured as shown in figure 1 and the

propulsion battery voltage (Vb) is recorded. Before any vehicle crash

test, Vb must be equal to or greater than the nominal operating voltage

as specified by the vehicle manufacturer. It is anticipated that Vb

after the crash will be approximately the same as Vb before the crash.

After the crash, a Vb greater than zero is required in order to conduct

the remainder of this procedure. If Vb after the crash is zero, this

indicates that a short across the propulsion battery has occurred,

which precludes the remainder of this test procedure. A short across

the propulsion battery may be conspicuous by virtue of arcing, fire,

and/or component meltdown.

S7.7.4 The voltage is measured as shown in figure 2 and the

voltage (V1) between negative side of the propulsion battery and the

vehicle chassis is recorded.

BILLING CODE 4910-59-P

[[Page 54658]]

[GRAPHIC] [TIFF OMITTED] TP13OC98.002

[GRAPHIC] [TIFF OMITTED] TP13OC98.003

[[Page 54659]]

S7.7.5 The voltage is measured as shown in figure 3 and the

voltage (V2) between the positive side of the propulsion battery and

the vehicle chassis is recorded. It is anticipated that the sum of the

absolute values of V1 and of V2 will approximate the absolute value of

Vb.

[GRAPHIC] [TIFF OMITTED] TP13OC98.004

S7.7.6 If V1 is greater than or equal to V2, insert a standard

known resistance (Ro) between the negative side of the propulsion

battery and the vehicle chassis. With the Ro installed, measure the

voltage (V1'') as shown in figure 4 between the negative side of the

propulsion battery and the vehicle chassis. Calculate the electrical

isolation (Ri) according to the formula shown. This electrical

isolation value (in ohms) divided by the nominal operating voltage of

the propulsion battery (in volts) must be equal to or greater than 500.

[GRAPHIC] [TIFF OMITTED] TP13OC98.005

[[Page 54660]]

S7.7.7 If V2 is greater than V1, insert a standard known

resistance (Ro) between the positive side of the propulsion battery and

the vehicle chassis. With the Ro installed, measure the voltage and

record the voltage (V2') between the positive side of the propulsion

battery and the vehicle chassis as shown in figure 5. Calculate the

electrical isolation (Ri) according to the formula shown. This

electrical isolation value (in ohms) divided by the nominal operating

voltage of the propulsion battery (in volts) must be equal to or

greater than 500.

[GRAPHIC] [TIFF OMITTED] TP13OC98.006

Issued on: October 1, 1998.

L. Robert Shelton,

Associate Administrator for Safety Performance Standards.

[FR Doc. 9826796 Filed 10-9-98; 8:45 am]

BILLING CODE 4910-59-C