[Federal Register Volume 60, Number 188 (Thursday, September 28, 1995)]
[Rules and Regulations]
[Pages 50124-50137]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-23986]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
49 CFR Part 571
[Docket No. 94-70, Notice 3]
RIN 2127-AF35
Federal Motor Vehicle Safety Standards; Door Locks and Door
Retention Components
AGENCY: National Highway Traffic Safety Administration (NHTSA),
Department of Transportation (DOT).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: This final rule amends the Federal motor vehicle safety
standard pertaining to door locks and door retention components. This
rule extends the standard's requirements, currently applicable only to
side doors, to the back doors of passenger cars and multipurpose
passenger vehicles (MPV) so equipped, including hatchbacks, station
wagons, sport utility vehicles, and passenger vans, with a gross
vehicle weight rating (GVWR) of 4,536 kilograms (kg) (10,000 pounds) or
less. Further, to allow for differences between side doors and back
doors, including the different directions in which they open in
relation to the vehicle, this rule amends certain performance
requirements and test procedures to make them appropriate for back
doors. Extension of the standard to back doors will reduce the
likelihood of occupants being ejected through the back doors of
vehicles in the event of a crash, thereby reducing fatalities and
serious injuries.
DATES: This final rule is effective September 1, 1997.
The incorporation by reference of the Society of Automotive
Engineers material listed in this document is approved by the Director
of the Federal Register.
Any petition for reconsideration of this rule must be received by
NHTSA not later than October 30, 1995.
ADDRESSES: Petitions for reconsideration should refer to the docket and
notice numbers noted above for this rule and be submitted to Docket
Section, National Highway Traffic Safety Administration, 400 Seventh
Street, S.W., Room 5109, Washington, DC 20590. Docket hours are from
9:30 a.m. to 4:00 p.m., Monday through Friday. Telephone (202) 366-
4949.
FOR FURTHER INFORMATION CONTACT: For other than legal issues: Dr.
William Fan, Office of Vehicle Safety Standards, National Highway
Traffic Safety Administration, 400 Seventh Street, SW, Washington, DC
20590. Telephone (202) 366-4922; FAX (202) 366-4329.
For legal issues: Walter Myers, Office of Chief Counsel, National
Highway Traffic Safety Administration, 400 Seventh Street, SW,
Washington, DC 20590. Telephone (202) 366-2992; FAX (202) 366-3820.
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Background
(a) Current Provisions
(1) Full requirements
(i) Latch/striker assemblies
(ii) Hinges
(iii) Locks
(2) Abbreviated requirements
(i) Hinged cargo doors
(ii) Sliding doors
(3) Test procedures
(b) Agency Review of Back Door Openings
(c) Notice of Proposed Rulemaking
(1) Rationale
(2) Proposed Test Procedures for Back Door Latches
(i) Load Test One
(ii) Load Test Two
(iii) Load Test Three
(iv) Inertia load
(3) Proposed Test Procedures for Back Door Hinges
(i) Load Test One
(ii) Load Test Two
(iii) Load Test Three
(4) Back Door Locks
(5) Additional Considerations
(6) Costs and Benefits
II. Overview
III. Public Comments and Agency Responses
(a) Vehicle Population Trends
(b) Load Requirements and Test Procedures
(1) Magnitude of test loads.
(2) Directions of Test Loads One and Two
(3) Test Load Three
(4) Inertia load requirements.
(5) Abbreviated requirements for back doors
(6) Secondary latched position
(7) Incorporating latch/hinge tests with others
(c) Interior Lock Mechanisms
(d) Vehicle and Other Exclusions
(e) Lead Time
(f) Definitions
(g) Belt Use
IV. Cost/Benefit Analysis
(a) Projected Vehicle Fleet
(b) Costs and Potential Benefits
(1) Agency analysis of cost data
(2) Estimated lives saved
(3) Estimated cost/benefit ratio
V. Rulemaking Analyses and Notices.
(a) E.O. 12866 and DOT Regulatory Policies and Procedures
(b) Regulatory Flexibility Act
(c) E.O. 12612 (Federalism)
(d) National Environmental Policy Act
(e) Paperwork Reduction Act
(f) Civil Justice Reform
I. Background
(a) Current Provisions
Federal Motor Vehicle Safety Standard (Standard) No. 206, Door
locks and door retention components (49 CFR 571.206), specifies
performance requirements for side door locks and retention components
including latches, hinges, and other supporting means. These
requirements are intended to minimize the likelihood of occupants being
ejected from the vehicle in the event of a crash. The standard applies
to passenger cars, MPVs, and trucks, and provides that components on
any side door leading directly into a compartment containing one or
more seating accommodations must comply with the standard. The full
requirements of the standard apply to side doors other than sliding
doors and cargo-type doors, to which more abbreviated requirements
apply, as discussed below.
Excluded from the standard are folding doors, roll-up doors, doors
designed to be easily attached to or removed from vehicles manufactured
for operation without doors, and side doors equipped with wheelchair
lifts that are linked to either an audible or visible alarm system that
is activated when the door is open.
[[Page 50125]]
(1) Full Requirements
(i) Latch/striker assemblies. Each door latch and striker assembly
must have a fully latched position and a secondary latched position.
The secondary latched position serves as a backup to the fully latched
position in the event the fully latched position is not properly
engaged.
The standard requires that the latch and striker assembly, when in
the fully latched position, must not separate when a longitudinal load
of 11,000 Newtons (2,500 pounds) or a transverse load of 8,900 Newtons
(2,000 pounds) is applied to the latch. A ``longitudinal'' load is
applied parallel to the vehicle's longitudinal, or lengthwise,
centerline and perpendicular to the latch face. A ``transverse'' load
is applied perpendicular to the vehicle's longitudinal centerline, in
the direction of door opening. Further, a door latch must not disengage
from the fully latched position when an inertia load of 30g is applied
to the latch/striker system in either the longitudinal or the
transverse direction.1 Finally, the standard requires that the
latch/striker assembly must not separate when a longitudinal or a
transverse load of 4,450 Newtons (1,000 pounds) is applied to the latch
while in the secondary latched position.
\1\ ``Inertia'' is the property of matter that requires that a
load be applied on a body to accelerate it, calculated by
multiplying the mass of a body by its acceleration.
---------------------------------------------------------------------------
(ii) Hinges. The standard requires each hinge system to support the
door and not separate when a longitudinal load of 11,000 Newtons (2,500
pounds) is applied. Further, each hinge system must not separate when a
transverse load of 8,900 Newtons (2,000 pounds) is applied.
(iii) Locks. Each door must be equipped with a locking mechanism
that has an operating means on the interior of the vehicle. Further,
when the locking mechanism is engaged in front side door locks, the
outside handle or other outside latch release mechanism must be
inoperative. In passenger cars and MPVs, when the locking mechanisms
are engaged in rear side door locks, both the inside and outside door
handles or other latch release mechanisms must be inoperative.
(2) Abbreviated Requirements
(i) Hinged cargo-type doors. ``Cargo-type door'' is defined in the
standard as ``a door designed primarily to accommodate cargo loading
including, but not limited to, a two-part door that latches to
itself.'' These doors are required to have only the fully latched
position, not the secondary latched position. Each latch system must
not separate when a longitudinal load of 11,000 Newtons (2,500 pounds)
or a transverse load of 8,900 Newtons (2,000 pounds) is applied. The
hinges on these doors are required to support the door and shall not
separate when a longitudinal load of 11,000 Newtons or a transverse
load of 8,900 Newtons is applied.
(ii) Sliding doors. The track and slide combination or other
supporting means for each sliding door shall not separate when a total
transverse load of 17,792 Newtons (4,000 pounds) is applied with the
door in the closed position.
(3) Test Procedures
Under Standard No. 206, latch and hinge assemblies are tested
individually as components and not as part of the vehicle structure to
which they are attached. The standard incorporates the test procedures
set forth in Society of Automotive Engineers (SAE) Recommended Practice
J839b, Passenger Car Side Door Latch Systems, May 1965 (SAE J839b), and
SAE Recommended Practice J934, Vehicle Passenger Door Hinge Systems,
July 1965 (SAE J934). The provisions of SAE J934 do not apply to piano-
type hinges, however. For those hinges, the arrangement of the test
fixture shall be altered as required so that the test load will be
applied to the complete hinge.
(b) Agency Review of Back Door Openings
Although Standard No. 206 applies only to side doors of passenger
cars, MPVs, and trucks, NHTSA has reviewed the potential safety
problems associated with back door openings on vehicles so equipped
several times in recent years. An agency report entitled Hatchback,
Tailgate, and Back Door Opening in Crashes and Occupant Ejection
through the Back Area issued on April 5, 1990 (1990 report) (NHTSA
docket no. 90-08-GR-001) concluded that the back doors of vehicles so
equipped opened in 5-6 percent of crashes that required towing from the
scene (hereinafter referred to as ``towaway crashes''), while side
doors opened in 1-3 percent of such crashes. The report was based on
1982-1986 and 1988 data from the National Accident Sampling System
(NASS) and the 1988 Fatal Accident Reporting System (FARS). Further, a
hatchback or tailgate was found to be about 3 times as likely to open
as one of the front side doors and 7-8 times as likely to open as one
of the rear side doors. The data also showed that rollovers accounted
for about 53 percent of back door openings, 23 percent of left front
door openings and 40 percent of right front door openings. However,
although back doors opened more frequently than side doors, only 1
percent of back door openings resulted in occupant ejection, as opposed
to 8-13 percent occupant ejections through front side door openings.
Finally, depending on the methodology used to analyze the data, NHTSA
calculated the fatalities due to back door ejections in 1988 to be
between 93 and 130.
Also on April 5, 1990, NHTSA wrote to 9 manufacturers: Chrysler,
Ford, General Motors, Honda, Mazda, Nissan, Toyota, Volkswagen, and
Volvo asking their comments on the issue of back door openings and
requesting information on their back door latch/lock designs. Of the 8
that responded, only Mazda reported that some of its models had back
doors that met the requirements of Standard No. 206. All indicated,
however, that they did not consider back door openings to be a
significant safety problem and argued that the proper use of seat belts
is the best way to prevent occupant ejections.
By Federal Register notice dated November 20, 1990 (55 FR 48261),
the agency denied a June 19, 1990 petition for rulemaking from the
Insurance Institute for Highway Safety (IIHS) to extend the
requirements of Standard No. 206 to back doors. Citing the 1990 report
and the comments of the 8 manufacturers responding to NHTSA's April 5,
1990 letter, the agency stated that of the 25 people ejected through
back doors as reported in the 1982-1988 NASS data, only one was using a
seat belt. Thus, the agency agreed at that time that the increased use
of seat belts in rear seats would be a more effective means of reducing
back door ejections. The agency determined, therefore, that there was
not a safety need significant enough to justify the suggested
rulemaking, and that extending the then-current side door requirements
to back doors would not be the most effective means of reducing back
door ejections.
On January 21, 1994, the agency issued a report entitled Door
Opening and Occupant Ejection through Rear Hatches, Tailgates, and
Other Back Doors (1994 report) (NHTSA docket no. 90-06-N03-001), which
updated the 1990 report. Based on NASS and FARS data from 1988-1992,
NHTSA estimated that there are 147 fatalities and 189 serious injuries
annually resulting from ejections through hatches, tailgates, and other
back doors. About 95 percent of those victims were not properly belted
and about 10 percent of the improperly belted victims were children
under 10.
[[Page 50126]]
Rollovers accounted for about 35 percent of left front door openings,
40 percent of right front door openings, and 42 percent of back door
openings. Finally, the data showed that the most common damage
associated with door openings was damage to the latch/striker
assemblies: 60 percent for left front door openings, 50 percent for
right front door openings, and 71 percent for back door openings.
(c) Notice of Proposed Rulemaking
(1) Rationale
In view of the number of fatalities and injuries resulting from
back door ejections, NHTSA published a Notice of proposed rulemaking
(NPRM) on August 30, 1994, proposing to extend the requirements of
Standard No. 206 to the back doors of passenger cars and MPVs with a
GVWR of 4,536 kg (10,000 pounds) or less, including hatchbacks,
passenger vans, station wagons, and sport utility vehicles. In
addition, the agency proposed certain modifications to the test
procedures applicable to back doors.
Based on agency data, NHTSA believes that its side door latch
requirements for passenger cars reduce the risk of ejection in rollover
crashes by 15 percent, thereby saving an estimated 400 lives per year.
Thus, although the agency has acknowledged that increased use of safety
belts is effective in reducing vehicle ejections, extending Standard
No. 206 requirements to back doors would help reduce injuries and
fatalities resulting from back door ejections of unbelted occupants.
Further, because of the increasing popularity of vehicles equipped with
back doors, especially passenger vans, this safety problem may become
more serious unless preventive measures are taken.
As noted in the NPRM, there is a greater variety of designs of back
doors than of side doors. While most side doors open to the side and
have hinges on their front and latches on the rear, back doors may open
upward, rearward or to the side, and have latches and hinges on the
top, bottom or side. In addition, back doors may be vertical or sloped
when viewed from the side.
Nevertheless, the NPRM pointed out four basic designs of back doors
typically used in production vehicles:
(i) Door opens upward, with a single latch (or striker) centered at
the bottom of the door with a single striker (or latch) on the back
door sill or floor panel;
(ii) Door opens sideways, with latch on the door and striker on the
door frame, such as back doors on large station wagons;
(iii) Split doors with top, typically of glass, opening upward and
bottom tailgate opening downward, with striker at the bottom of the top
door and latches or rod/pin connectors at the top and sides of the
tailgate, such as back doors of sport utility vehicles; and
(iv) Double cargo-type doors, a 2-part door that latches to itself
with one latch located at the center between the doors, such as the
back doors of some cargo vans.
Because of the wide variety of back door designs and the variation
in latch and hinge orientations in relation to the vehicle, NHTSA
indicated in the NPRM that directions in which test loads are applied
should be specified in relation to the orientation of each latch and
hinge. The agency further indicated that latches and hinges on doors
that open upward should meet load requirements in 3 rather than in 2
directions. For those reasons, NHTSA proposed to modify the test
procedures applicable to back door latches and hinges, as discussed
below.
In addition to proposing modifications to the existing latch/
striker test procedures, the agency announced that it was considering
applying the secondary latched position requirement currently
applicable to side door latches to some or all back door latches. The
agency therefore requested comments on what types of back doors should
be included or excluded from this requirement and why.
(2) Proposed Test Procedures for Back Door Latches
(i) Load Test One. For back doors, NHTSA proposed basically the
same test as the longitudinal test, that is, applying a load
perpendicular to the face of the latch, utilizing the same test loads.
Rather than refer to the test as ``longitudinal load,'' however, NHTSA
proposed to refer to it as ``Load Test One,'' since most back door
latches are oriented so that a load applied parallel to the vehicle
longitudinal centerline would not be equivalent to the longitudinal
test of side door latches.
(ii) Load Test Two. The agency proposed to apply to back doors a
test corresponding to the transverse load test for side doors, but
rather than apply the load in the direction of door opening, NHTSA
would apply the load in the direction of the fork-bolt opening and
parallel to the plane of the latch face. The agency proposed to use the
same test loads as in the transverse load test, but would refer to this
test as ``Load Test Two.''
(iii) Load Test Three. NHTSA proposed to require latches on doors
that open upward to meet load requirements in a third direction that is
orthogonal, i.e. perpendicular, to both of the directions in which
loads are applied in Load Tests One and Two. The set-up for Load Tests
Two and Three would be identical, except that in Load Test Three, the
latch would be mounted in a position perpendicular to those in Load
Tests One and Two. The agency requested comments on whether a load of
11,000 Newtons (2,500 pounds) or 8,900 Newtons (2,000 pounds) should
apply to Load Test Three.
(iv) Inertia load. In view of the many orientations of back doors,
NHTSA proposed that back door latches meet the 30g inertia load
requirement in any direction, as opposed to a limited number of
directions for side door latches. The agency requested comments on the
appropriateness of that proposal.
(3) Proposed Test Procedures for Back Door Hinges
The agency stated that the same considerations concerning load
orientations apply to back door hinges as to back door latches.
Accordingly, the agency proposed the following 3 load tests for hinges:
(i) Load Test One. Load is applied perpendicular to the hinge face
plate;
(ii) Load Test Two. Load is applied perpendicular to the axis of
the hinge pin and parallel to the hinge face plate; and
(iii) Load Test Three. In this test, which is applicable to the
hinges on doors that open upward, the load is applied parallel to the
axis of the hinge pin.
The agency requested comments whether the load for the three hinge
tests should be 8,900 Newtons (2,000 pounds) or 11,000 Newtons (2,500
pounds).
(4) Back Door Locks
The agency stated that it was considering extending the door lock
requirements of Standard No. 206 to some or all back door locks, and
requested comments on that issue.
(5) Additional Considerations
The agency requested comments on the following issues:
(i) To what extent should full versus abbreviated requirements
apply to back doors?
(ii) Are the proposed test requirements clear and appropriate for
all back doors?
[[Page 50127]]
(iii) Which and how many hatchbacks, station wagons, passenger
vans, and sport utility vehicles would need to be upgraded to meet the
proposed requirements? What is the consumer cost and relative strength
increase for each upgrade?
(iv) Identify and/or provide the agency with any data that would
assist the agency in quantifying the safety or other benefits of the
proposed requirements.
(6) Costs and Benefits
Assuming an effective date on or before September 1, 1997, the
agency estimated that about 1.5 million hatchbacks, 0.4 million station
wagons, 1.6 million sport utility vehicles, and 1.8 million passenger
vans, for a total of 5.3 million vehicles expected to be produced
during model year 1998, could be affected by these amendments. In a
NHTSA evaluation of 8 passenger minivan back door latches (docket No.
97-70-N 01), representing about 1 million vehicles sold in 1993, 2
failed the longitudinal load test (equivalent to Load Test One) and
another failed the transverse load test (equivalent to Load Test Two).
All the others exceeded the proposed load requirements. The 5 complying
latches represent about 50 percent (0.5 million) of the 1993 minivan
sales. The agency concluded, therefore, that about half the minivan
fleet already meets or exceeds the requirements proposed in the NPRM.
Although the back door latch assemblies of hatchbacks, station wagons
and sport utility vehicles were not tested, NHTSA considered that since
most of the 1.6 million sport utility vehicles have back door latch
systems similar to those of minivans, about 50 percent (0.8 million) of
sport utility vehicles would also meet the proposed requirements.
Although the remaining vehicles could require some upgrading of their
current back door locks and retention components, the agency estimated
that the proposed requirements would not require more than minor
changes in either latch, hinge, or locking mechanisms.
The retail costs of the tested latches ranged from $22.03 to
$81.74. The costs of the 3 failing latches were $23.52, $63.19, and
$81.74. The tests showed that a latch that complies with Standard No.
206 need not be more expensive than one that does not. Assuming,
therefore, that no more than 4.0 million vehicles may require upgrades
and that the cost of the upgrades may not be higher than that of
current designs, NHTSA estimated that the cost of extending the
requirements of Standard No. 206 to the back doors of the proposed
vehicles would be minimal.
Compliance tests for back door locks and retention components would
typically be conducted with similar, but perhaps slightly modified,
test equipment of the type currently used to evaluate side door locks
and retention components. NHTSA estimated, therefore, that no
significant test equipment costs should be incurred by manufacturers.
The agency pointed out that of the deaths and injuries that occur
annually involving occupant ejection through back doors, over 80
percent involve hinge or latch damage. The agency anticipated,
therefore, that the proposed upgrades should reduce such deaths and
injuries, although the agency is not able to quantify such benefits or
costs. Accordingly, the agency solicited comments and data on that
issue.
II. Overview
Today's final rule is based on the NPRM of August 30, 1994,
summarized above. This final rule:
* Extends the motor vehicle door latch, hinge, and lock
requirements of Standard No. 206 to the back doors of passenger cars
and MPVs so equipped, including hatchbacks, station wagons, sport
utility vehicles, and passenger vans with a GVWR of 4,536 kg (10,000
pounds) or less;
* Revises existing performance requirements and test procedures,
insofar as they apply to back doors, and establishes an additional test
for back door latches and hinges;
* Requires inertia load testing of back door latches in 3
directions instead of in any direction, as proposed in the NPRM;
* Requires door locks and interior and exterior release mechanisms
only for back doors equipped with interior door handles or that lead
directly into compartments containing one or more seating
accommodations, instead of all back doors as proposed in the NPRM;
* Revises definition of ``back door'' from that proposed in the
NPRM to exclude passenger car trunk lids as well as doors and windows
composed entirely of glazing materials where the latches and/or hinges
are mounted directly onto the glazing;
* In addition to adding a definition of ``back door,'' adds
definitions of ``auxiliary door latch,'' ``fork-bolt,'' ``fork-bolt
opening,'' and ``primary door latch'' to the standard; and
* Replaces the reference to Society of Automotive Engineers (SAE)
Recommended Practices J839b, Passenger Car Side Door Latch Systems, May
1965, in S5.1.1.1, S5.1.1.2, and S5.2.1 with reference to the revised
version of J839, which is dated June 1991; and the reference in S5.1.2
and S5.2.2 to SAE J934, Vehicle Passenger Door Hinge Systems, July
1965, with reference to the revised version of J934, which is dated
July 1982.
III. Public Comments and Agency Responses
Fourteen interested parties submitted comments in response to the
NPRM, including 2 private citizens, 2 safety organizations, 2
automotive trade associations, and 8 motor vehicle manufacturers. A
summary of their significant comments and the agency's responses are
set forth below.
(a) Vehicle Population Trends
The American Automobile Manufacturers Association (AAMA) commented
that, since 1989, sales of hatchback style vehicles have been steadily
declining, being replaced by sales of passenger minivans and sport
utility vehicles. Referring to NHTSA's 1994 report, AAMA stated that
back door openings in towaway crashes were the highest for hatchback
cars (18,059) and lowest for minivans (767). AAMA argued that minivan
and sport utility vehicles are rapidly replacing hatchback style
vehicles and that the already low incidence of door openings and
ejections should further decline as the vehicle mix changes in the
future.
While NHTSA does not dispute the fact that the total number of back
door openings in minivans is lower than in hatchback cars, the agency
believes this discrepancy to be due primarily to the larger number of
hatchbacks on the road compared to minivans. In its 1994 report, NHTSA
analyzed the incidence of back door openings as a rate per 100 towaway
crashes for minivans, utility vehicles, and hatchback cars. The
agency's analysis shows that back door openings for minivans is about
1.9 compared to 3.6 for hatchback cars. The back door opening rates for
utility vehicles were 2.6 and 4.1 for large and compact utility
vehicles respectively. The overall rate for all light trucks equipped
with back doors and hatches is 2.7 percent. Based on this data, AAMA's
contention that increasing numbers of minivans in the fleet will reduce
the number of back door openings and ejections in future crashes is not
well founded, although if the observed rates continue into the future,
the problem size could diminish somewhat.
(b) Load Requirements and Test Procedures
(1) Magnitude of Test Load
Toyota Motor Corporate Services of North America, Inc. (Toyota)
suggested
[[Page 50128]]
that a test load of 8,900 Newtons (2,000 pounds), as proposed for Load
Test Two, be applied to all back doors. Toyota further suggested that
since the NPRM made no reference to doors equipped with more than one
latch/striker set, the specified load be divided by the number of
latch/striker sets fitted to a single door, and that the load so
divided be applied simultaneously to each latch/striker set. Advocates
for Highway and Auto Safety (Advocates) suggested that a load of 11,000
Newtons (2,500 pounds) be applied in all tests. Mazda (North America),
Inc. (Mazda) believed that NHTSA simply proposed the same test loads as
presently specified in Standard No. 206 and, along with Rockwell,
suggested that the test loads for back doors be based on real world
test data.
In 1989, NHTSA published a study entitled An Evaluation of Door
Locks and Roof Crush Resistance of Passenger Cars--FMVSS Nos. 206 and
216 (1989 study). That study, based on actual crash data, showed that
the requirements of Standard No. 206 are responsible for a 15 percent
reduction in side door ejections in rollover accidents. Real world
crash data also showed that latches that met the 11,000 (2,500 pounds)
and 8,900 Newton (2,000 pounds) loads in the longitudinal and
transverse directions respectively were effective in preventing door
openings while latches that did not meet those test requirements were
not effective in preventing door openings. NHTSA believes, therefore,
that the extension of the requirements of Standard No. 206 to back
doors as proposed, including the test loads proposed in the NPRM, would
be effective in preventing back door openings and occupant ejection
through that route.
Based on the real world crash data discussed above, NHTSA has also
concluded that the appropriate test load for Load Test Three is 8,900
Newtons (2,000 pounds). In most production back door latch designs, the
latch would fail only if the striker disengages. This is seldom likely
when loads are applied in the third direction perpendicular to the
directions of Load Tests One and Two. In this test, the striker is
usually pressing against the side of the fork bolt and the latch
casing. If properly designed, a latch should be able to sustain a large
force in this third direction. The results of the agency's back door
latch tests showed that most latches tested can sustain a load of 8,900
Newtons (2,000 pounds).
NHTSA does not agree with Toyota's suggestion that the specified
test load should be divided by the number of latches fitted to a single
door. Real world crash data show that latch failures are the dominant
cause of door openings and that they are seldom loaded symmetrically.
Since side door latches that individually meet the requirements of
Standard No. 206 have significantly reduced side door openings in
crashes and have saved an estimated 400 lives per year, NHTSA has
decided that the proposed requirements should be applied to each back
door latch tested. However, this final rule does specify separate
requirements for the primary and auxiliary latches, as discussed in
III(b)(5) below.
(2) Directions of Load Tests One and Two
AAMA commented that the proposed load test directions of Load Tests
One and Two need clarification. AAMA argued that while side door
latches and hinges are typically mounted in body and door planes that
intersect at approximately 90 deg. to each other, back door latches and
hinges may be at angles other than 90 deg.. Nissan stated that NHTSA's
proposed definition of ``hinge face plate'' does not adequately
describe certain hinge systems. Specifically, Nissan stated that in
some vehicle back doors, when closed, their hinges are positioned such
that the faces do not bear load perpendicular to the mounting surfaces.
Nissan further stated that some hinge systems may not even have an
actual ``face.'' Thus, for a more objective test procedure, Nissan
suggested applying Load Test One at the intersection of a line along
the longitudinal vertical plane that passes through the center points
of 2 hinges and the plane passing through 2 hinges and the latch. Load
Test Two would then be applied along the longitudinal vertical plane in
a direction perpendicular to Load Test One. AAMA stated that the
addition of a definition of ``latch face'' is necessary to determine
the surfaces to which the test loads must be perpendicular or parallel.
Nissan stated that it interprets the term ``face plate'' to mean the
area of the hinge that is mounted to the body and to the door and that
acts as the load-bearing surface that supports the weight of the door.
NHTSA believes that Nissan's suggested loading directions will not,
in many cases, be consistent with the loading directions of the hinges
in actual crashes and that a new set of test devices other than those
called for in J934 might be necessary to conduct Nissan's tests. NHTSA
believes that its 3 orthogonal tests will cover all loading directions
experienced in real world tests, irrespective of the configuration or
orientation of the back doors. The agency continues to believe that the
hinge tests should be conducted in accordance with SAE J934 and that
Load Tests One and Two correspond to the longitudinal and transverse
loads, respectively, as called for in SAE J934. The third direction is
orthogonal to the other two. The agency believes, therefore, that the
proposed test procedures are appropriate.
NHTSA acknowledges that the NPRM did not contain definitions of
``face plate'' and ``latch face.'' The NPRM did, however, refer in
proposed Load Test One to SAE J839 where details of load directions are
given. NHTSA believes that SAE J839 provides sufficient explanation of
those terms and that no further definition is necessary in this rule.
(3) Load Test Three
Toyota, AAMA, and Rockwell Automotive (Rockwell) opposed Load Test
Three for doors that open upward. These commenters stated, without
explaining the basis for their position, that Load Test Three is
unnecessary, and that NHTSA has not demonstrated any benefits that
support the need for the test. Rockwell commented that a third load
test is not the most effective means of reducing occupant ejections.
That commenter suggested instead that a systems approach be taken in
which the vehicle body together with the door system, taken as a whole,
should be required to pass load tests. Conversely, the Insurance
Institute for Highway Safety (IIHS) and Advocates both supported Load
Test Three and urged that a load of 11,000 Newtons (2,500 pounds) be
applied. IIHS suggested that Load Test Three be applied to all doors,
including side doors.
NHTSA does not agree with Toyota, AAMA, and Rockwell that Load Test
Three is not necessary. NHTSA notes that there are many design
differences between side doors and back doors with regard to their
mounting locations and orientations. Except for cargo-type doors and
side-swing station wagon doors, most back doors open either in the
rearward (longitudinal) or upward (vertical) directions. Those
directions correspond generally to the longitudinal and transverse
loading directions of side doors. As opposed to side doors, however,
latch/hinge failure can occur in upward or rearward-opening back doors
due to force in the third direction orthogonal to those directions. For
example, in the event of a rear side impact, the back door latches and
hinges are subject to a large force perpendicular to the upward and
rearward-opening directions. Agency tests showed that the back doors of
[[Page 50129]]
some minivans opened when struck at the rear quarter panel. NHTSA
believes that this happens when the door panel is displaced sideways,
away from the plane of the door frame, forcing the latch to disengage.
NHTSA believes, therefore, that in view of the loads to which back
doors are subjected in some crashes, it is necessary to test back door
latches and hinges in a third direction, orthogonal to the directions
of loading to which side doors are normally subjected.
NHTSA declines to adopt the suggestion of IIHS that Load Test Three
be applied to all doors. It is beyond the scope of the NPRM and this
final rule to amend the requirements applicable to side doors, since
this rulemaking action applies only to back doors. In any case, since
side doors of production vehicles normally do not open in a vertical
direction, NHTSA sees no need at this time to require side door latch
and hinge tests in the direction of Load Test Three.
When proposing in the NPRM to apply Load Test Three to doors that
open upward, it was NHTSA's belief that such doors were equipped with
latch/striker assemblies only on the bottoms of the doors (see II.A.(1)
of the NPRM, 59 FR 44694). NHTSA has learned, however, that the upward-
swinging back doors of certain models of MPVs are equipped with latch/
striker assemblies on the sides of the doors. Testing those latches in
the direction of Load Test Three would be meaningless because in that
test the load is applied in a direction in which such doors are not
likely to open in a crash. This is the same reason Load Test Three does
not apply to side doors. Accordingly, NHTSA has decided to apply Load
Test Three to the hinges of back doors that swing upward to open, and
to the latch/striker assemblies of upward-swinging doors that are
equipped with a single latch/striker assembly.
(4) Inertia Load Requirements
As previously noted (see section I(a) above), Standard No. 206
currently provides that side door latches shall not disengage when an
inertia load of 30g is applied in the longitudinal and transverse
directions. The NPRM proposed to require back doors to withstand an
inertia load of 30g in any direction. Nine commenters addressed this
issue, 7 of whom opposed and 2 supported the proposal.
Toyota and Nissan stated that the omni-directional inertia load
requirement is unnecessary and impractical, and that the current
requirements applicable to side doors are sufficient to simulate real
world crash experience. AAMA, Rockwell, and Volkswagen of America, Inc.
(VW) stated that the omni-directional inertia load requirement is not
practical and suggested instead that the load be applied in not more
than 3 directions. Isuzu Motors Limited, Japan (Isuzu) argued that
there is no need for an inertia load test for back doors. Mitsubishi
Motors America, Inc (Mitsubishi) stated that the requirement, as
proposed, would create repeatability problems. On the other hand,
Advocates and IIHS supported the proposal, IIHS stating that the
proposal is reasonable because inertia loads can occur in any direction
in real world crashes.
NHTSA proposed the inertia load test requirement in the NPRM in the
belief that in view of the many different orientations of back door
latches and because real-world inertia forces are omni-directional, a
large number of inertia load tests in various directions would be
required to ensure adequate latch performance. However, in view of the
manufacturers' comments that the requirement to test in any direction
would be impractical and almost impossible to achieve, NHTSA is
persuaded that, for practicability reasons, the number of inertia tests
needs to be limited. Manufacturers argued that a requirement to test in
any direction would require testing in theoretically infinite
directions, which not only is not practical, but may not give
sufficient emphasis on the worst case loading directions in real-world
crashes. While it is difficult to predict inertial loading directions
in real-world crashes, test requirements in the 3 principal directions
would suffice to ensure that the latch would be unlikely to fail in
many of the crash modes. In view of this, NHTSA concludes that 3 test
load directions are adequate to ensure acceptable latch performance in
the various loading conditions experienced in real world crashes. NHTSA
has decided, therefore, to require inertia loads of 30g be applied to
back door latch systems in the 3 directions specified in Load Tests
One, Two, and Three.
(5) Abbreviated Requirements for Back Doors
As stated in the summary of current provisions in section (I(a))
above, Standard No. 206 specifies a set of full requirements for
regular side doors and abbreviated requirements for cargo-type and
sliding side doors. Ford Motor Company (Ford) and Isuzu argued that
back doors and hatches are used primarily for cargo area access rather
than for passenger access, therefore the abbreviated requirements
applicable to hinged cargo-type and sliding side doors would likewise
be appropriate for all back doors.
The agency has evaluated this suggestion and disagrees that only
the abbreviated requirements should be applicable to all back doors.
The agency's intent in this rulemaking action is to prevent the back
door ejection of occupants by upgrading the latch/striker and hinge
systems of back doors to reduce the incidence of unintended back door
opening. NHTSA believes that this cannot be achieved by applying only
the abbreviated requirements of Standard No. 206 to all back doors.
Accordingly, the agency has decided that the primary latches of all
back doors must meet the requirements of both the fully latched and the
secondary latched positions. Auxiliary latches, if any, defined as a
latch other than the primary latch of a multi-latch door system, need
only meet the abbreviated requirements, that is, the requirements for
the fully latched position (they need not have a secondary latch
position or meet the strength requirements for the secondary latch).
On a related issue, AAMA commented that certain vehicle models are
manufactured with more than one back door latch/striker set. AAMA
suggested that, in that situation, it should be sufficient that one
latch include both a fully latched and a secondary latched position
while the others, designated as auxiliary latches, have a fully latched
position only. NHTSA considers the AAMA suggestion to be reasonable
because typically, the primary latch/striker assembly directly connects
the left and the right segments of a double cargo type door system to
each other while the auxiliary latches connect one segment of the door
system to the roof and/or floor of the vehicle. In a crash, door
openings would occur as a result of primary latch failure. Thus, even
if the auxiliary latch(es) failed, the door segments could still be
held together by the primary latch set because the loading on the
different latches is in different directions. For that reason,
simultaneous failure of the primary and auxiliary latches is highly
unlikely, occurring only in very severe crashes. Accordingly, only the
primary latch system in multiple-latch door systems is required to meet
both the fully latched and the secondary latched position requirements
of Standard No. 206. Auxiliary latches are required to meet the fully
latched requirements only. They are not required to have a secondary
latch position or meet the strength requirements for a secondary latch.
``Primary'' and ``auxiliary'' latches
[[Page 50130]]
are defined in the regulatory text of this final rule.
(6) Secondary Latched Position
AAMA, Mazda, Nissan, and Toyota opposed the proposal to require a
secondary latched position in back doors on the basis that such a
requirement would increase costs to manufacturers. Advocates and
Rockwell, on the other hand, supported the proposal. NHTSA disagrees
that this proposal would increase costs. On current designs, both the
fully latched and secondary latched positions are provided by the same
fork bolt detent lever. Typically, side door latches have two teeth on
the detent lever with one tooth corresponding to the fully latched
position and the other to the secondary latched position. The design
load specifications for the latch assembly must be based on the load
requirements for the fully latched position. Since the test load for
the secondary latched position is less than that for the fully latched
position, NHTSA believes the incremental cost for providing an
additional tooth on the fork bolt detent lever to be negligible. This
belief is based on a NHTSA cost/weight study, Cost Comparison--Two MY
93 Rear Door Latch and Striker Sets, NHTSA docket no. 94-70, Notice 01-
001, in which the agency examined the costs of the 2 least expensive
back door latches from the 8 latches it evaluated. One of the latches
complied with the current requirements of Standard No. 206, while the
other did not. The better latch had the lowest production and purchase
prices. In addition, the better latch had both the fully latched and
the secondary latched positions, while the inferior latch had only the
fully latched position. As previously noted, NHTSA believes that the
back door latches of most current production minivans and station
wagons already have 2 latch positions. Accordingly, the agency does not
believe that back door latches would require any major design changes
in order to comply with the proposed fully latched and secondary
latched position requirements.
(7) Incorporating Latch/Hinge Tests With Other Tests
Rockwell commented that NHTSA should consider incorporating latch/
hinge tests into an existing crash test or a modified existing crash
test. Advocates suggested that NHTSA consider roof strength performance
standards in determining how roof strength in full rollover crashes
affects back door retention.
The agency agrees with the concept of combining tests where
possible, and has done so in certain recent rules (see, for example,
S5.3.1 and S5.3.2, Standard No. 214, Side impact protection. S5.3.1
requires that any side door struck by the moving deformable barrier
shall not totally separate from the vehicle. S5.3.2 requires that any
door, including a rear hatchback or tailgate, not struck by the moving
deformable barrier shall not disengage from the latched position, nor
shall the latches or hinges separate or pull out of their anchorages).
Taking such a step would not eliminate the necessity of bench testing
of latches as components, however, since the agency wishes to assure
the safety of latches under all possible crash conditions and loadings.
To ensure that latches are safe in all crash modes, a system level test
would require several tests which would be impractical and costly. In
addition, if such an approach were used, the agency would need to
develop new test procedures for such latch evaluation.
(c) Interior Lock Mechanisms
Except for most station wagons with third seats in the rear of the
vehicle, many production vehicles have neither locking mechanisms nor
inside door handles on their back doors. Thus, unlatching cannot be
accomplished from the inside. The agency has received several
complaints about this, citing the potential danger of being trapped in
the rear compartment area of a vehicle, especially young children, in
fire or submersion situations. While agency accident data do not show
this as a significant safety problem, NHTSA nevertheless requested
comments in the NPRM on whether the requirements for front and/or rear
side door locks should be extended to back doors.
Four commenters opposed requiring door locks on the back doors, one
supported it, and one (Mitsubishi) requested clarification of the term
``locking mechanism with an operating means in the interior of the
vehicle'' (S4.1.3, Standard No. 206). AAMA, Toyota, and VW argued that
there is no need or justification for back door locks. AAMA and Toyota
repeated their assertions that back doors are not intended for
passengers, and Rockwell stated that a properly designed system does
not need a lock. Nevertheless, Toyota stated that lock requirements
would be appropriate for back doors designed for passenger ingress and
egress. VW stated that if a back door locking requirement were adopted,
both the inside and outside door handles or other release mechanism
should be inoperative when the locking mechanism is engaged. Rockwell
stated that if a locking requirement were adopted, the inside handle
should be disengaged either electrically or manually when the vehicle
is moving. Rockwell also stated that if a lock were required, an inside
handle should also be required. Advocates stated that locking
requirements should be prescribed for all back doors, regardless of
design, in view of increased risk of multiple back door ejections
because of back door lock disengagements.
Standard No. 206 requires door locks in order to reduce
unintentional door openings due to impact upon or movement of the
inside or outside door handles (see 33 FR 6465, April 27, 1968). The
standard requires the locks to engage so as to render the exterior
front door handles inoperative and both the exterior and interior rear
side door handles inoperative. Standard No. 206 does not specifically
require doors to have door handles. However, many manufacturers already
voluntarily provide inside handles on back doors of station wagons with
third seats.
NHTSA concludes that back doors that lead directly into a passenger
compartment or that are otherwise already equipped with an interior
door handle shall be equipped with a locking mechanism with operating
means in both the interior and exterior of the door. The reason for
this is similar to the reason door locks are required for side doors,
i.e., to prevent inadvertent door openings due to impact upon or
movement of the interior or exterior door handles. NHTSA acknowledges
that the back doors of some vehicles so equipped are designed for
loading and unloading cargo rather than passengers. Nevertheless,
sometimes those doors are also used for ingress and egress of back seat
occupants. Therefore, if doors designed primarily for loading and
unloading cargo lack an interior door handle, no door lock is required.
If an interior door handle is present, this rule requires a means for
making the door handle (a door release mechanism) inoperative when the
locking mechanism is engaged. Further, when the locking mechanism is
engaged, both the inside and outside door handles or other latch
release controls must be inoperative.
(d) Vehicle and Other Exclusions
Five commenters addressed the applicability of the proposal to
passenger motor vehicles with a GVWR of 4,536 kg (10,000 pounds) or
less. The National Truck Equipment Association (NTEA) stated that most
multi-stage produced vehicles can demonstrate compliance with safety
standards only to the extent that the chassis manufacturer passes
through its
[[Page 50131]]
certification. NTEA stated further that many such manufacturers will
permit their certification to pass through only if no changes or
alterations are made to their components by the final-stage
manufacturer. Thus, NTEA argued that in cases where doors are widened
or lengthened, such as for ambulances and vehicles for physically
challenged persons, there can be no pass-through. In those situations,
NTEA said that final-stage manufacturers, most of which are small
businesses, would be obliged to assume the burden and expense of
compliance testing themselves. NTEA suggested, therefore, that NHTSA
either lower the GVWR level for this rule to 2,721 kg (6,000 pounds) or
exclude all vehicles built on a truck type chassis in 2 or more stages
and equipped with a body designed for carrying cargo, or work-
performing or specialty equipment such as that found on ambulances,
fire trucks, and the like.
AAMA suggested that hinged windows, liftglass, and glass hatches
should be exempt from the proposed requirements because glazing in
those configurations typically would yield in a crash before the hinges
and latches would fail. Similarly, Isuzu suggested that the glass top
portion of split doors on which the striker and hinges are installed on
the glass itself should be exempt. Mazda stated that extending Standard
No. 206 requirements to back doors that have large window openings or
large glass areas will have little or no effect in reducing unbelted
back door ejections since occupants could be ejected through the window
opening. Finally, similar to NTEA's suggestion, Nissan suggested that
back doors designed for loading and unloading cargo be excluded from
the rule.
NHTSA recognizes that there is a substantial number of vehicles
produced by businesses involved in manufacturing vehicles in more than
one stage, and in converting or altering MPVs (e.g., van converters).
Many of these are small businesses. Final-stage manufacturers typically
install truck bodies and/or work-related equipment on chassis. Alterers
modify the structure of new, completed vehicles. Under NHTSA's
regulations, a final-stage manufacturer must certify that the completed
vehicle conforms to all applicable safety standards, and alterers must
certify that the altered vehicle continues to comply with all
applicable safety standards.
The impact of this rule on commercial vehicles will not be
significant. This rulemaking does not apply to buses or trucks such as
cargo vans and many specially-designed and equipped commercial
vehicles. The proposal only applied to passenger motor vehicles such as
station wagons, hatchbacks, and MPVs with a GVWR of 4,536 kg (10,000
pounds) or less. An MPV is defined in 49 CFR 571.3 as a motor vehicle
``designed to carry 10 persons or less'' (emphasis added). Examples of
MPVs include passenger vans and sport utility vehicles. MPVs also
include motor homes, ambulances, and other customized passenger
vehicles. Except for ambulances, some of those vehicles do not have
back doors and will therefore not be affected by this rule.
In response to NTEA's concerns, as to final-stage manufacturers and
alterers that produce vehicles that are subject to today's rule, it
should not be difficult for those entities to satisfy their
certification responsibilities with respect to Standard No. 206. NHTSA
believes that many final-stage manufacturers should be able to meet the
requirements of Standard No. 206 by utilizing the latch and hinge
systems that were originally certified by the incomplete vehicle
manufacturer as complying with the standard. Even if the final-stage
manufacturer or alterer cannot use the original latch and hinge
systems, it should not be unduly burdensome for those entities to
obtain back door latch systems that comply with Standard No. 206 and
certify compliance of their vehicles with the standard. Latch designs
similar to those used for side doors can be used for back doors in many
MPVs and are commercially available at low cost. Side doors of new
vehicles are currently subject to Standard No. 206, and this rule
essentially only extends those side door requirements to back doors.
Thus, the certification responsibilities of final- stage manufacturers
and alterers under Standard No. 206 with respect to back doors should
be very similar to their current responsibilities under Standard No.
206 with respect to side doors. Moreover, the test burdens associated
with this final rule are not significant.
This rule specifies a relatively simple component test that
provides for bench testing of latches and hinges. It does not specify a
dynamic test requirement. Manufacturers and alterers may, but are not
required, to test their vehicles using the test procedures specified by
Standard No. 206. The test procedures of Standard No. 206, like those
of all other Federal motor vehicle safety standards, set forth the test
procedures NHTSA uses in its compliance testing. In view of the
standards to which manufacturers and alterers already certify and the
manufacturing operations they undertake, final-stage manufacturers and
alterers should have the necessary technical expertise and resources to
certify to the back door standards. Alternatively, those final-stage
manufacturers and alterers who install back door latches could require
that their suppliers provide certification that their back door latch
systems comply with the requirements of the standard. NHTSA does not
require final-stage manufacturers and alterers themselves to conduct
the testing specified in this final rule.
NHTSA agrees with the suggestions of AAMA and Isuzu that windows
and doors on which latch/hinge systems are mounted directly onto the
glazing (glass, glass/plastic, or plastic) should be excluded from the
standard. In virtually all such cases, the glazing would fail before
the latch and/or hinge fails. Thus, strengthening the latches and
hinges on those doors would not prevent them from opening. The agency
disagrees, however, with Mazda's suggestion that doors containing large
glass areas be excluded. While it may be true that occupants could be
ejected through large windows in back doors, the agency believes that
ejection is less likely when the doors remain closed than if they
opened. With a closed door, the occupant may be retained by the door
structure and not ejected through the window. Thus, the agency has
included back doors in this final rule, regardless of the size of the
windows in those doors, because upgrading the strength of latches and
hinges is needed to better ensure that those doors remain closed in a
crash.
Finally, the agency does not agree with Nissan's suggestion that
back doors designed for loading and unloading cargo be excluded from
the rule. Even though back doors in many vehicles may be designed
primarily for cargo loading and unloading, an unbelted occupant can be
ejected through those doors in a crash. NHTSA's data show that back
doors in general open more frequently than side doors, and that the
majority of back door ejections occurred from hatchback cars, passenger
vans, and utility vehicles. The back doors of those vehicles are
designed primarily for cargo loading and unloading. However, occupant
ejections through those doors, especially unbelted occupants, are a
serious safety problem. Accordingly, by this final rule the agency
extends the requirements of Standard No. 206 to the latch and hinge
assemblies of back doors of passenger cars and MPVs, and to the locks
and interior release mechanisms of back doors equipped with interior
door handles or that are designed for passenger ingress and egress.
Nissan's suggestion, therefore, is not adopted.
[[Page 50132]]
(e) Lead Time
NHTSA proposed in the NPRM a lead time of 2 years following the
first September 1 after publication of a final rule, i.e., a lead time
of 2-3 years. Six comments were received on this proposal. AAMA stated
that more lead time and an appropriate phase-in period would be
necessary to allow the time to evaluate and make necessary changes.
Nissan and Mazda urged an effective date of 3 and 4 years,
respectively, after the issuance of the final rule to allow for
revisions, possibly extensive, of function and styling of body
structures. Ford commented that it could not meet the proposed date
because of the testing necessary to determine what changes would be
needed, and suggested a phase-in period starting with model year 1998.
VW stated that it could meet the proposed 2-year lead time if NHTSA
adopted the substantive suggestions in their comments. Advocates
commented that the proposed effective date was reasonable.
The agency continues to believe that most of the latches and hinges
currently installed in back doors would meet the requirements of this
final rule with little or no design changes, as discussed above.
Manufacturers did not provide an analysis of why they could not comply
with the proposed lead time. They only requested generally more time,
without explaining why more time was necessary. Therefore, in the
absence of data to the contrary, the agency considers September 1, 1997
to be sufficient lead time to meet the new requirements.
(f) Definitions
AAMA, Toyota, Nissan, and Mitsubishi commented that the proposed
definition of ``back door'' is not clear because it neither
distinguishes between doors and cargo compartment covers such as trunk
lids of passenger cars, nor between doors and hinged windows. AAMA also
stated that latch ``face'' needs to be defined to facilitate
identification of the surface to which the test load must be parallel
or perpendicular. AAMA also said that while door latches typically have
planar (flat 2-dimensional characteristic) mounting surfaces, some
designs may have mounting surfaces which are not planar or which are
multi-planar. Toyota and Nissan stated that ``hinge face plate'' needs
to be defined, Toyota suggesting that it should be defined as the
mounting side of the hinge on the body of the vehicle.
The agency has decided, in response to these comments, to modify
the definition of ``back door'' so that it clearly excludes trunk lids
on passenger cars. The agency does not, however, adopt Toyota's and
Nissan's suggestions to define ``latch face'' and ``hinge face plate''
since SAE J839 and SAE J934 provide detailed drawings showing how to
mount the component on the test fixture and how and where to apply the
required test loads.
(g) Belt Use
AAMA, Mazda, and Rockwell referred to NHTSA's 1990 denial of the
IIHS petition, commenting that the situation has not changed that much
since then, and that the agency's current analysis still has not shown
that upgrading latch and hinge performance will reduce back door
ejections. IIHS expressed approval that NHTSA is conducting this
rulemaking at this time.
The commenters are correct that seat belts are effective in
preventing ejections. However, as explained above, more than 95 percent
of the back door ejections are passengers who were unbelted at the time
of the crash. Since NHTSA's data show that fatalities from back door
ejections have increased from an estimated 93 to 130 in the time period
1982-1988 to an estimated 147 in the time period 1988 to 1992, finding
innovative ways to encourage seat belt use, as suggested by Mazda, is
not by itself sufficient to address the problem of unbelted occupants.
Thus, the agency believes that the significant increase in fatalities
through back door ejections now justifies rulemaking action to upgrade
the performance requirements of back door latches, hinges, and locks.
IV. Cost/Benefit Analysis
(a) Projected Vehicle Fleet
According to 1992 data available to NHTSA, 20 percent of passenger
cars were hatchbacks and station wagons, while approximately 54 percent
of all light trucks and vans (LTVs) were sport utility vehicles and
passenger vans. Also, based on available data, the agency estimates
that approximately 9.4 million passenger cars and 6.2 million LTVs will
be sold in 1997. Applying the 1992 percentages to those figures, NHTSA
estimates that of the 15.6 million vehicles predicted to be sold in
1997, approximately 5.2 million will be equipped with back doors,
compared to 4.2 million in 1992. This represents an estimated 24
percent increase in the number of model year 1997 vehicles potentially
affected by this rule compared to the number of model year 1992
vehicles that could have been so affected.
Similarly, the total vehicle population has increased since 1990
and is expected to continue to increase in the future. While the
passenger car fleet has held relatively steady since 1990, the LTV
fleet has increased by 17 percent. Assuming the continuation of those
trends, NHTSA estimates a total vehicle fleet of approximately 194
million passenger cars and LTVs in the 1998-1999 period, up from a
total vehicle fleet of 181.5 million in 1992. This represents an
increase of about 7 percent. Assuming a similar increase in the target
vehicle population, the agency estimates that in 1998 and beyond there
will be approximately 160 fatalities and 200 serious injuries annually
resulting from back door ejections.
(b) Costs and Potential Benefits
(1) Agency Analysis of Cost Data
As discussed above in section I(c)(6) regarding the costs and
benefits of the proposal, NHTSA tested the back door latches of eight
1993 model year minivans for compliance with the current requirements
of Standard No. 206 for the fully latched position. Two failed the
longitudinal load test (equivalent to proposed Load Test One) and 1
failed the transverse load test (equivalent to Load Test Two), while
the remaining latches complied with the standard's current
requirements. The 3 failing latches had the highest, second highest and
second lowest purchase prices. The lowest price latch gave a
performance superior to the others and included both the fully latched
and the secondary latched positions. In addition, the agency conducted
a cost/weight study using 2 minivan latches that had the lowest and the
second lowest prices among the 8 latches tested. The results showed
that the estimated production cost for those 2 latches was less than
$4.00, which is less than 15 percent of the consumer replacement cost
charged by dealers. All latches, except the one that failed the Load
Test Two requirement, had secondary latched positions. That latch has
since been modified. The 1995 model year latch complies with all three
load tests.
The agency also conducted latch tests on 12 different model year
1995 vehicles, using Load Tests One, Two, and Three. A total of 6 tests
were conducted, composed of Load Test One in the fully and secondary
latched positions; Load Test Two in the fully and secondary latched
positions; and Load Test Three in the left and right loading
directions. The test vehicles included 5 hatchbacks, 2 station wagons,
and 5 MPVs. The 5 hatchbacks and 1 MPV did not have the secondary
latched position. Among the 5
[[Page 50133]]
hatchback latches tested, 1 failed all tests, another failed Load Test
One in both positions and Load Test Two in the secondary latched
position. The remaining 3 hatchback latches failed Load Tests One and
Two in the secondary latched position. Two station wagons passed all 6
tests. The MPV which did not have a secondary latched position failed
Load Test Two in the fully latched position. One MPV failed Load Tests
One and Two in the secondary latched position, another failed Load Test
One in the fully latched position. Finally, a sport van failed 4 of the
6 tests. These tests showed again that latch price is not directly
related to the latch's level of performance. The tests also showed that
many of the current production light passenger vehicles already comply
with the back door latch requirements of this rule. NHTSA believes that
all production latches could comply with the requirements of this rule
with only minor modifications, and that the costs of complying with the
secondary latched position requirement are negligible to none. Thus,
NHTSA believes that extending the requirements of Standard No. 206,
including the addition of Load Test Three, will not result in any
significant increase in production costs. The agency also concludes
that the cost of complying with the secondary latched position
requirement, if needed, could cost up to $1.00 per latch.
The agency also tested the back door hinge systems of 11 production
vehicles. Load Test Two was not conducted on one vehicle hinge and Load
Test Three was not conducted on 2 others. Those three components were
judged to be strong, however, and their ultimate strength is expected
to exceed the requirements as proposed. Aside from those 3, all hinges
passed all the tests to which they were subjected.
To estimate the incremental new vehicle costs from upgrading
hinges, the agency began by examining the replacement part costs of
both the side door and back door hinges of a series of production
vehicles. All vehicles had side doors with 2 hinges, but some of their
back doors had auxiliary hinges that allowed those doors to open in
different directions. The consumer replacement prices for primary
hinges ranged from $40 to $120 for a pair of side door hinges and $20
to $100 for a pair of back door hinges. The agency calculated that the
weighted average consumer price of replacement side and back door
hinges would be about the same, approximately $53 per pair. Thus, NHTSA
estimates that the incremental consumer cost to upgrade back door
hinges, if improvements were required, would range from $0 to $20 with
an average of about $10 per pair of replacement hinges. NHTSA
emphasizes that those prices are estimated consumer replacement costs
which are usually much higher than new vehicle consumer costs. Thus,
based on NHTSA's estimates that incremental production costs are less
than 15 percent of retail consumer costs, NHTSA estimates that the
incremental production costs for necessary hinge improvements, if
needed, would range from $0 to $3.00.
With respect to the issue of back door locks and interior release
handles, NHTSA examined 24 station wagons, some with back doors
designed for passenger ingress. Fourteen had either rear or side-facing
third seats in the rear of the vehicles, the other 10 did not have the
third row of seats. Twelve of the 14 vehicles in the former group had
inside door handles, while none in the latter group did. It appears,
therefore, that most manufacturers have already voluntarily addressed
the issue of occupant ingress and egress through back doors by
providing inside door handles on their station wagons equipped with a
third row of seats. Accordingly, since most mid and large size station
wagons already have a locking system similar to that specified in this
final rule, as do ambulances and motor homes, NHTSA estimates that
incremental costs for lock improvements needed to comply with the
requirements of this final rule are minimal, no more than $1.00 per
vehicle.
(2) Estimated Lives Saved
NHTSA has previously noted that the door latch requirements of
Standard No. 206 have reduced the risk of side door ejections in
rollover crashes by at least 15 percent, saving at least 400 lives per
year (see section I(c)(6) above on costs and benefits of the proposal).
The 1990 report concluded that a hatchback or tailgate was 3 times as
likely to open in a crash as one of the front doors and 7-8 times as
likely to open as one of the rear side doors. Further, the back door of
a van is 4 times as likely to open as one of the front doors and twice
as likely to open as the right rear side door (passenger vans seldom
have a left side rear door). NHTSA believes, therefore, that extending
the requirements of Standard No. 206 to back doors will be as effective
in reducing back door openings as the standard's requirements have been
in reducing side door openings. This is because the back door
requirements will include 3 tests instead of the 2 currently required.
Accordingly, by applying that effectiveness value to the estimated
noncomplying target vehicle population, NHTSA estimates that 13 lives
will be saved and 17 serious injuries prevented annually by extending
the requirements of Standard No. 206 to back doors.
(3) Estimated Cost/Benefit Ratio
As discussed in section IV(a) above on the projected vehicle fleet,
NHTSA projects that approximately 5.2 million vehicles equipped with
back doors will be produced in 1997. This target vehicle fleet is
expected to consist of 1.9 million passenger cars and 3.3 million other
types of light passenger vehicles. NHTSA further estimates that
approximately 0.4 of the 1.9 million passenger cars will be station
wagons (0.24 million mid and large size station wagons and 0.16 small
station wagons) and 1.5 million will be hatchbacks. Based on the
agency's test results, NHTSA estimates that approximately 190,000 of
the mid and large size station wagons and approximately 20,000 small
station wagons will be equipped with third seats and, therefore,
required to meet the proposed door lock requirements. In addition to
station wagons, an estimated 2,500 ambulances, mostly with 2 back
doors, and 20,000 motor homes, mostly with 1 back door, will be
produced in 1997. The agency estimates, therefore, that approximately
240,000 vehicles produced in 1997 will be required to be equipped with
back door locks. The agency also estimates that 1.5 million hatchbacks
and 1.1 million MPVs produced in 1997 may require some minor latch
modifications other than providing a secondary latched position at
minimal cost. In all, NHTSA estimates that about 55 percent of the
vehicles expected to be produced in 1997 will require some minor
improvements in their latch and/or lock designs under this rule at a
total estimated cost of up to $1,740,000, not including potential costs
for compliance testing. The agency also concludes that hinge
improvements will not be necessary. Accordingly, using the projected
safety benefits of this final rule, that is, prevention of
approximately 13 fatalities and 17 serious injuries annually, the
annual cost of this rulemaking action is estimated to be approximately
$112,000 per equivalent life saved.
V. Rulemaking Analyses and Notices
(a) Executive Order No. 12866 and DOT Regulatory Policies and
Procedures
This rulemaking document was not reviewed under E.O. 12866,
Regulatory
[[Page 50134]]
Planning and Review. NHTSA has considered the impact of this rulemaking
action under the DOT's regulatory policies and procedures and has
determined that it is not ``significant'' within the meaning of those
policies and procedures.
The amendments promulgated by this final rule extend the
requirements of Standard No. 206 to back doors of passenger cars and
MPVs, including hatchbacks, passenger vans, station wagons and sport
utility vehicles with a GVWR of 4,536 kg (10,000 pounds) or less that
are so equipped. The agency believes that the economic impact of this
rulemaking action is minimal both to manufacturers and consumers since
agency data indicate that many back door latches, hinges, and locks
already comply with the requirements of this rule. If any changes must
be made by manufacturers to comply with this rule, the agency believes
that such changes will be minor in nature, of very little or no cost,
and easily capable of being accomplished within the lead time provided.
As noted above, the total cost of bringing the remaining noncompliant
vehicles into compliance is estimated to be up to a total of
$1,740,000. Accordingly, a full regulatory evaluation was not prepared.
(b) Regulatory Flexibility Act
NHTSA has considered the effects of this rulemaking action under
the Regulatory Flexibility Act. I hereby certify that the amendments
promulgated by this final rule will not have a significant impact on a
substantial number of small entities. Accordingly, a regulatory
flexibility analysis has not been prepared.
The agency believes that few, if any, motor vehicle manufacturers
qualify as small businesses. Small businesses, small organizations, and
small governmental units may be affected by this rulemaking action only
to the extent that they could pay a few dollars more for the vehicles
that they purchase with the complying back door latches, hinges, and
locks.
(c) Executive Order 12612, Federalism
NHTSA has analyzed this rulemaking action in accordance with the
principles and criteria of Executive Order No. 12612 and has determined
that this rule does not have sufficient federalism implications to
warrant the preparation of a Federalism Assessment.
(d) National Environmental Policy Act
NHTSA has analyzed this rulemaking action for the purposes of the
National Environmental Policy Act and has determined that
implementation of this rulemaking action will not have any significant
impact on the quality of the human environment.
(e) Paperwork Reduction Act
In accordance with the Paperwork Reduction Act of 1980, P.L. 96-
511, NHTSA states that there are no information collection requirements
associated with this rulemaking action.
(f) Civil Justice Reform
This rule does not have any retroactive effect. Under 49 U.S.C.
30103(b), whenever a Federal motor vehicle safety standard is in
effect, a state or political subdivision thereof may prescribe or
continue in effect a standard applicable to the same aspect of
performance of a motor vehicle only if the standard is identical to the
Federal standard. However, a state may prescribe a standard for a motor
vehicle or equipment obtained for its own use that imposes a higher
performance requirement than the Federal standard. 49 U.S.C. 30161 sets
forth a procedure for judicial review of final rules establishing,
amending or revoking Federal motor vehicle safety standards. A petition
for reconsideration or other administrative proceedings is not required
before parties may file suit in court.
List of Subjects in 49 CFR Part 571
Imports, Motor vehicle safety, Motor vehicles, Rubber and rubber
products, Tires, Incorporation by reference.
PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS
In consideration of the foregoing, 49 CFR Part 571 is amended as
follows:
1. The authority citation for Part 571 continues to read as
follows:
Authority: 49 U.S.C. 322, 30111, 30115, 30117, and 30166;
delegations of authority at 49 CFR 1.50.
2. Section 571.206 is amended by revising S1; adding the
definitions of ``auxiliary door latch,'' ``back door,'' ``fork-bolt,''
``fork-bolt opening,'' and ``primary door latch'', in alphabetical
order, to S3; revising S4, S4.1.1.1, S4.1.1.2, S4.1.2, S4.2.1.1,
S4.2.1.2, S4.2.2, and S4.3; adding S4.4 through S4.5; revising the
heading of S5.1; revising S5.1.1.1, S5.1.1.2, S5.1.2, S5.2.1, S5.2.2,
and S5.3; revising the heading of S5.2; adding S5.4 through S5.5; and
adding Figure 1 to the end of the section, to read as follows:
Sec. 571.206 Standard No. 206, Door locks and door retention
components.
S1. Purpose and Scope. This standard specifies requirements for
door locks and door retention components including latches, hinges, and
other supporting means, to minimize the likelihood of occupants being
thrown from the vehicle as a result of impact.
* * * * *
S3. Definitions.
Auxiliary door latch means a latch or latches, other than the
primary latch or latches, fitted to a back door or back door system
that is equipped with more than one latch.
Back door means a door or door system on the back end of a vehicle
through which passengers can enter or depart the vehicle, or cargo can
be loaded or unloaded, except--
(1) the trunk lid of a passenger car whose trunk is separated from
the passenger compartment by a partition; and
(2) a door or window composed entirely of glazing material whose
latches and/or hinges are attached directly onto the glazing material.
* * * * *
Fork-bolt means the part of the door latch that engages the striker
when in a latched position.
Fork-bolt opening means the direction opposite to that in which the
striker enters to engage the fork-bolt.
Primary door latch means, with respect to a back door or back door
system, the latch or latches equipped with both the fully latched
position and the secondary latched position.
* * * * *
S4. Requirements. Components on any side door leading directly into
a compartment that contains one or more seating accommodations, and
components on any back door of a passenger car or multipurpose
passenger vehicle manufactured on or after September 1, 1997 with a
gross vehicle weight rating of 4,536 kilograms (10,000 pounds) or less
shall conform to this standard. A particular latch or hinge assembly
(i.e., test specimen) need not meet further requirements after having
been subject to and having met any one of the requirements of S4 or
S5.1 through S5.4. Components on folding doors, roll-up doors, doors
that are designed to be easily attached to or removed from motor
vehicles manufactured for operation without doors, and doors that are
equipped with wheelchair lifts and that are linked to an alarm system
consisting of either a flashing visible signal located in the driver's
compartment or an alarm audible to the driver that is activated when
the door is open, need not conform to this standard.
[[Page 50135]]
S4.1 Hinged Side Doors, Except Cargo-Type Doors.
* * * * *
S4.1.1.1 Longitudinal Load. The door latch and striker assembly,
when in the fully latched position, shall not separate when a
longitudinal load of 11,000 Newtons (2,500 pounds) is applied. When in
the secondary latched position, the door latch and striker assembly
shall not separate when a longitudinal load of 4,450 Newtons (1,000
pounds) is applied.
S4.1.1.2 Transverse Load. The door latch and striker assembly,
when in the fully latched position, shall not separate when a
transverse load of 8,900 Newtons (2,000 pounds) is applied. When in the
secondary latched position, the door latch and striker assembly shall
not separate when a transverse load of 4,450 Newtons (1,000 pounds) is
applied.
* * * * *
S4.1.2 Door Hinges. Each door hinge system shall support the door
and shall not separate when a longitudinal load of 11,000 Newtons
(2,500 pounds) is applied. Similarly, each door hinge system shall not
separate when a transverse load of 8,900 Newtons (2,000 pounds) is
applied.
* * * * *
S4.2 Hinged Cargo-Type Side Doors.
S4.2.1 Door Latches.
S4.2.1.1 Longitudinal Load. Each latch system, when in the latched
position, shall not separate when a longitudinal load of 11,000 Newtons
(2,500 pounds) is applied.
S4.2.1.2 Transverse Load. Each latch system, when in the latched
position, shall not separate when a transverse load of 8,900 Newtons
(2,000 pounds) is applied. When more than one latch system is used on a
single door, the load requirement may be divided among the total number
of latch systems.
S4.2.2 Door Hinges. Each door hinge system shall support the door
and shall not separate when a longitudinal load of 11,000 Newtons
(2,500 pounds) is applied, and when a transverse load of 8,900 Newtons
(2,000 pounds) is applied.
S4.3 Sliding Side Doors. The track and slide combination or other
supporting means for each sliding door shall not separate when a total
transverse load of 17,800 Newtons (4,000 pounds) is applied, with the
door in the closed position.
* * * * *
S4.4. Hinged Back Doors.
S4.4.1 Door Latches. Each back door system shall be equipped with
at least one primary latch and striker assembly.
S4.4.1.1 Load Test One. The primary door latch and striker
assembly, when in the fully latched position, shall not separate when a
load of 11,000 Newtons (2,500 pounds) is applied in the direction
perpendicular to the face of the latch (corresponding to the
longitudinal load test for side door latches) such that the latch and
the striker anchorage are not compressed against each other. When in
the secondary latched position, the primary latch and striker assembly
shall not separate when a load of 4,450 Newtons (1,000 pounds) is
applied in the same direction.
S4.4.1.2 Load Test Two. The primary door latch and striker
assembly, when in the fully latched position, shall not separate when a
load of 8,900 Newtons (2,000 pounds) is applied in the direction of the
fork-bolt opening and parallel to the face of the latch (corresponding
to the transverse load test). Figure 1 depicts the loading direction
for this test. When in the secondary latched position, the primary
latch and striker assembly shall not separate when a load of 4,450
Newtons (1,000 pounds) is applied in the same direction.
S4.4.1.3 Load Test Three. The primary door latch and striker
assembly on back doors equipped with a latch and striker assembly at
the bottom of the door and that open upward shall not disengage from
the fully latched position when a load of 8,900 Newtons (2,000 pounds)
is applied in a direction orthogonal to the directions specified in
S4.4.1.1 and S4.4.1.2 above.
S4.4.1.4 Inertia Load. The primary door latch shall not disengage
from the fully latched position when an inertia load of 30g is applied
to the door latch system, including the latch and its activation
mechanism with the locking mechanism disengaged, in the directions
specified in S4.4.1.1, S4.4.1.2, and S4.4.1.3.
S4.4.1.5 Auxiliary Door Latches. Each auxiliary back door latch
and striker assembly shall be provided with a fully latched position
and shall comply with the requirements specified in S4.4.1.1, S4.4.1.2,
and S4.4.1.4.
S4.4.2 Door Locks. Each back door system equipped with interior
door handles or that leads directly into a compartment that contains
one or more seating accommodations shall be equipped with a locking
mechanism with operating means in both the interior and exterior of the
vehicle. When the locking mechanism is engaged, both the inside and
outside door handles or other latch release controls shall be
inoperative.
S4.4.3 Door Hinges.
S4.4.3.1 Load Test One. Each back door hinge system shall support
the door and shall not separate when a load of 11,000 Newtons (2,500
pounds) is applied perpendicular to the hinge face plate (longitudinal
load test) such that the hinge plates are not compressed against each
other.
S4.4.3.2 Load Test Two. Each back door hinge system shall not
separate when a load of 8,900 Newtons (2,000 pounds) is applied
perpendicular to the axis of the hinge pin and parallel to the hinge
face plate (transverse load test) such that the hinge plates are not
compressed against each other.
S4.4.3.3 Load Test Three. Each hinge system on back doors that
open upward shall not separate when a load of 8,900 Newtons (2,000
pounds) is applied in the direction of the axis of the hinge pin.
S4.5 Sliding Back Doors. The track and slide combination or other
supporting means for each sliding door shall not separate when a total
longitudinal load of 17,800 Newtons (4,000 pounds) is applied, with the
door in the closed position. * * *
S5.1. Hinged Side Doors, Except Cargo-Type Doors. * * *
S5.1.1.1 Longitudinal and Transverse Loads. Compliance with
paragraphs S4.1.1.1 and S4.1.1.2 shall be demonstrated in accordance
with paragraph 5 of Society of Automotive Engineers Recommended
Practice J839, Passenger Car Side Door Latch Systems, June 1991.
S5.1.1.2 Inertia Load. Compliance with S4.1.1.3 shall be
demonstrated by approved tests or in accordance with paragraph 6 of
Society of Automotive Engineers Recommended Practice J839, Passenger
Car Side Door Latch Systems, June 1991.
S5.1.2 Door Hinges. Compliance with S4.1.2 shall be demonstrated
in accordance with paragraph 4 or 5, as appropriate, of Society of
Automotive Engineers Recommended Practice J934, Vehicle Passenger Door
Hinge Systems, July 1982. For piano-type hinges, the hinge spacing
requirements of SAE J934 shall not be applicable and arrangement of the
test fixture shall be altered as required so that the test load will be
applied to the complete hinge.
S5.2 Hinged Cargo-Type Side Doors.
S5.2.1 Door Latches. Compliance with S4.2.1 shall be demonstrated
in accordance with paragraphs 5.1 and 5.3, SAE Recommended Practice
J839, Passenger Car Side Door Latch Systems, June 1991. An equivalent
static test fixture may be substituted for that shown in Figure 2 of
SAE J839, if required.
[[Page 50136]]
S5.2.2 Door Hinges. Compliance with S4.2.2 shall be demonstrated
in accordance with paragraph 4 or 5, as appropriate, of SAE Recommended
Practice J934, Vehicle Passenger Door Hinge Systems, July 1982. For
piano-type hinges, the hinge spacing requirement of SAE J934 shall not
be applicable and arrangement of the test fixture shall be altered as
required so that the test load will be applied to the complete hinge.
S5.3 Sliding Side Doors. Compliance with S4.3 shall be
demonstrated by applying an outward transverse load of 8,900 Newtons
(2,000 pounds) to the load-bearing members at the opposite edges of the
door (17,800 Newtons (4,000 pounds) total). The demonstration may be
performed either in the vehicle or with the door retention components
in a bench test fixture.
S5.4 Hinged Back Doors.
S5.4.1 Door Latches.
S5.4.1.1 Load Tests One, Two, and Three. Compliance with S4.4.1.1,
S4.4.1.2, and S4.4.1.3 shall be demonstrated in the same manner as
specified in S5.1.1.1, except that the loads shall be in the directions
specified in S4.4.1.1, S4.4.1.2, and S4.4.1.3. The same test device may
be used for Load Tests Two and Three.
S5.4.1.2 Inertia Load. Compliance with S4.4.1.4 shall be
demonstrated in the same manner as specified in S5.1.1.2.
S5.4.2 Door Hinges. Compliance with S4.4.3.1, S4.4.3.2, and
S4.4.3.3 shall be demonstrated in the same manner as specified in
S5.1.2, except that the loads shall be in the directions specified in
S4.4.3.1, S4.4.3.2, and S4.4.3.3. The same test device may be used for
Load Tests Two and Three.
S5.5 Sliding Back Doors. Compliance with S4.5 shall be
demonstrated by applying an outward longitudinal load of 8,900 Newtons
(2,000 pounds) to the load bearing members at the opposite edges of the
door (17,000 Newtons (4,000 pounds) total). The demonstration may be
performed either in the vehicle or with the door retention components
in a bench test fixture.
BILLING CODE 4910-59-P
[[Page 50137]]
[GRAPHIC][TIFF OMITTED]TR28SE95.010
Issued on: September 22, 1995.
Ricardo Martinez,
Administrator.
[FR Doc. 95-23986 Filed 9-27-95; 8:45 am]
BILLING CODE 4910-59-C
