[Federal Register Volume 62, Number 39 (Thursday, February 27, 1997)]
[Proposed Rules]
[Pages 8906-8916]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-4762]


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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. 94-97; Notice 2]
RIN 2127-AF40


Federal Motor Vehicle Safety Standards; Roof Crush Resistance

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

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to revise the test procedures in 
Standard No. 216, Roof Crush Resistance, to make them more suitable to 
testing vehicles with highly sloped roofs or raised roofs. The current 
test procedure is intended to test the strength of the roof over the 
driver. It involves lowering a large test plate, inclined forward at a 
five degree angle, to an initial contact point near the leading edge of 
the roof. However, when the procedure is performed on certain rounded, 
aerodynamically-shaped roofs that may themselves slope at more than 
five degrees, small differences in test plate angle result in 
considerable variability in the location of the initial contact point, 
thus reducing the repeatability of the test results. Similarly, for 
vehicles with raised, irregularly shaped roofs (such as some converted 
vans), the initial contact point may not be above the driver, but on 
the raised rear portion of the roof, behind the driver.
    This proposal addresses these problems by specifying the use of a 
smaller test plate for use on vehicles on which the use of the current 
larger test plate would result in an initial contact point behind the 
driver. The rearward edge of the smaller test plate will be

[[Page 8907]]

over the front occupant compartment, so the initial contact point will 
be in that area.
    This proposal also changes the test procedure to align either test 
plate with the front of the roof, thus ensuring engagement of the 
vehicle's A-pillar.

DATES: Comment Date: Comments must be received by April 28, 1997.
    If adopted, the proposed amendments would become effective, and 
compliance required, 180 days following publication of the final rule.

ADDRESSES: Comments should refer to the docket and notice number of 
this notice and be submitted to: Docket Section, Room 5109, National 
Highway Traffic Safety Administration, 400 Seventh Street, SW, 
Washington, DC 20590. (Docket Room hours are 9:30 a.m.-4 p.m., Monday 
through Friday.)

FOR FURTHER INFORMATION CONTACT: The following persons by mail at the 
National Highway Traffic Safety Administration, 400 Seventh Street, 
S.W., Washington, DC 20590:
    For non-legal issues:
    Dr. William R. S. Fan, Office of Crashworthiness Standards, NPS-11, 
telephone (202) 366-4922, facsimile (202) 366-4329, electronic mail 
``[email protected]''.
    For legal issues:
    Mr. Paul Atelsek, Office of the Chief Counsel, NCC-20, telephone 
(202) 366-2992, facsimile (202) 366-3820, electronic mail 
``[email protected]''.
    Comments on this proposal must be sent to the docket and not to the 
contact persons.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Background
II. Petitions
    A. Recreation Vehicle Industry Association (RVIA)
    B. Ford Petition
III. Agency Request for Comments
IV. Comments on the Petitions
    A. Comments on the RVIA Petition and the suitability of Standard 
No. 220 test procedures for raised roof vehicles
    1. Passenger Vehicle Manufacturers and AAMA
    2. Second Stage Manufacturers and RVIA
    3. Safety Advocacy Groups
    B. Comments on the Ford Petition, and test plate orientation and 
size
    1. Passenger Vehicle Manufacturers and AAMA
    2. Safety Advocacy Groups
V. NHTSA research on the proposed test procedure
    A. Passenger Cars
    B. Raised Roof Converted Van Tests
VI. Agency response to the comments
    A. Issues related to the RVIA petition
    B. Issues related to the Ford petition
VII. Proposed Test Procedure and Requirements
VIII. Changes to the Regulatory Text
IX. Proposed Lead Time
X. Rulemaking Analyses and Notices
    A. Executive Order 12866 and DOT Regulatory Policies and 
Procedures
    B. Regulatory Flexibility Act
    C. Paperwork Reduction Act
    D. Executive Order 12612 (Federalism)
    E. Civil Justice Reform
XI. Submission of Comments

I. Background

    Federal Motor Vehicle Safety Standard (FMVSS) No. 216, Roof Crush 
Resistance, is intended to assure that vehicles have sufficient 
structural strength in the passenger compartment roof to resist 
crushing during rollover crashes. The test procedure involves securing 
the vehicle on a rigid horizontal surface, placing a test plate on the 
roof, and applying 1.5 times the unloaded vehicle weight (up to a 
maximum of 22,240 N, or 5,000 pounds, for passenger cars) to the test 
plate. The vehicle passes if the roof prevents the test plate from 
moving downward more than 127 mm (5 inches).
    The test procedure is designed to test the primary structural 
member supporting the roof over the front seats. That member is 
generally the A-pillar.
    In order to test the A-pillar, the test plate, which is 762 mm (30 
inches) wide by 1,829 mm (72 inches) long, is oriented in a way so that 
the initial contact point is at the top of the A-pillar. Its 1,829 mm 
dimension is parallel to the vertical plane through the longitudinal 
centerline of the vehicle, and tilted forward at a five degree angle. 
Its 762 mm dimension is tilted outward at a 25 degree angle so that its 
outboard side is lower than its inboard side. So oriented, the test 
plate is lowered until it contacts the vehicle. After the initial 
contact point is determined, the test plate is moved, maintaining its 
orientation, so that the initial contact point touches the underside of 
the test plate along the test plate's longitudinal centerline, 254 mm 
(10 inches) rearward of the centerline's forwardmost point. The test 
plate is then pushed downward in a direction perpendicular to its lower 
surface until a load of 1.5 times the unloaded vehicle weight (up to a 
maximum of 22,240 N, or 5,000 pounds, for a passenger car) has been 
applied.
    Although, as noted above, the intent underlying this test procedure 
is to load the area at the top of the A-pillar, the combined effect of 
the test plate and procedures and certain roof configurations may be 
the testing of other areas of the roof. Neither NHTSA nor the industry 
envisioned these configurations when the current test procedure was 
promulgated. In response to the problems created by these 
configurations, two members of the industry have petitioned the agency 
to modify the test procedure.

II. Petitions

A. Recreation Vehicle Industry Association (RVIA)

    RVIA, which represents small business van conversion manufacturers, 
is concerned that contoured or raised roof structures on certain second 
stage van conversions cannot be tested using the current test 
procedure. With only a five degree incline of the test plate, the 
initial contact point at the leading edge of the roof is supposed to be 
254 mm (10 inches) behind the forwardmost edge of the test plate. 
However, for some raised roofs, the initial contact point will be 
several inches behind the leading edge of the roof due to the roof 
geometry. This results in testing the raised roof structure (which is 
generally relatively weak) instead of the A-pillar over the front 
seats. Vehicles with these problem configurations include raised roof 
conversions of the Plymouth Voyager, Dodge Caravan, Chrysler Town & 
Country, Chevrolet Astro, and GMC Safari minivans.
    To address this situation, RVIA petitioned NHTSA to allow vans, 
motor homes and other multipurpose passenger vehicles, trucks, and 
buses that have raised roofs, to be tested in accordance with the test 
procedures in Standard No. 220, School Bus Rollover Protection. 
Standard No. 220 uses a larger test plate and distributes the same load 
evenly over the entire surface of the roof and all its supporting 
pillars, rather than concentrating the load on either side of the roof 
over the front seat.
    In making this request, RVIA reasoned that, since the modified 
vehicles would have met Standard No. 216 requirements prior to 
modification of their roofs, the A-Pillar strength would have been 
demonstrated. The Standard No. 220 test procedure could then be used to 
test the strength of the entire modified vehicle roof. There would be 
no need to repeat the Standard No. 216 test.

B. Ford Petition

    Ford is concerned that some Ford models with aerodynamic, rounded, 
roof designs result in initial contact points that are so far back on 
the roof that the front edge of the test plate is several inches behind 
the A-pillar when it is positioned as specified in the Standard. This 
occurs because the roofs slope longitudinally at an angle greater

[[Page 8908]]

than 5 degrees at their leading edge. Consequently, the roofs are 
loaded somewhere behind the A-pillar.
    In addition, Ford states that the long sloping roofs make 
repeatable testing difficult. The initial contact point is highly 
variable and dependent on the specific roof design. The initial contact 
point can move several inches if the plate angle or the level of the 
floor on which the test vehicle is placed are off by as little as one 
degree. This could lead to substantial differences in test results.
    Ford believes that the test procedures are contradictory. S6.2 of 
the standard says to ``[o]rient the test device as shown in Figure 1 * 
* *'', which shows the test plate in contact with the front corner of 
the roof, inclined longitudinally at an angle of 5 degrees. At the same 
time, S6.2(d) of the rule specifies that the initial contact point be 
254 mm (10 inches) from the front edge of the test plate. Thus, there 
is a conflict between the specifications in S6.2(d) and Figure 1 in the 
regulatory text for certain vehicles with highly sloped roofs.
    Ford believes NHTSA has not resolved this apparent conflict in a 
way that is in accordance with the initial intent underlying the 
standard, which is to load the front corner of the roof. NHTSA issued 
an October 3, 1980 letter of interpretation stating that the test plate 
should be positioned in accordance with the language of the regulatory 
text of S6.2(b), even if the leading edge of the test plate will not be 
forward of the A-pillar and the roof's leading edge, as depicted in the 
figure. Ford has followed this interpretation even though it believes 
that this approach does not test the actual resistance of the roof to 
being crushed in crashes.
    Ford petitioned NHTSA to amend Standard No. 216 to specify that the 
leading edge of the test plate should always be one inch forward of the 
leading edge of the roof. To accomplish this, Ford suggested the 
following language to replace S6.2(d):

    The initial contact point, or center of the initial contact 
area, is on the longitudinal centerline of the device. A plane 
perpendicular to the lower surface of the test device and 25 mm 
rearward of the front edge of the lower surface passes through the 
rearmost point of the opening in the body structure for the 
windshield.

    Ford also petitioned NHTSA to amend the test procedure to specify 
that all vehicles be tested with the body sills, rather than the 
chassis, mounted on the rigid surface, and that all roof rack 
components that could interfere with initial contact between the test 
plate and the roof be removed prior to testing.

III. Agency Request for Comments

    In a request for comments published December 27, 1994, NHTSA 
granted the RVIA and Ford petitions, but expressed reservations about 
the solutions suggested by the petitioners. The details of NHTSA's 
reaction to the petitions can be seen in that 1994 document (59 FR 
66504), and will merely be summarized here.
    In response to the RVIA's petition to use the test procedures of 
Standard No. 220 for raised roof vehicles, NHTSA expressed concern that 
adopting RVIA's approach would trade off increased roof crush 
protection for rear seat occupants with diminished protection for front 
seat occupants. Because most deaths and injuries in these vehicles are 
to front seat occupants, and RVIA submitted no data to quantify the 
trade-offs in protection, NHTSA wanted to conduct research to examine 
them. In addition, NHTSA was concerned that the roof strength in the 
area of the A-pillars might be affected by raised roof conversions, 
thus compromising the basis for the original manufacturer's 
certification under Standard No. 216.
    In response to Ford's petition to position the leading edge of the 
test plate one inch forward of the leading edge of the roof, NHTSA 
observed that consistent positioning of the test plate over the front 
of the roof would not ensure that area of the roof would be tested. 
This would occur because Ford's suggested language retained the 5 
degree angle of tilt (a detailed explanation is given below). In 
addition, NHTSA was concerned that Ford's suggested positioning could 
reduce the stringency of the test for some vehicles.
    The agency requested public comment on the changes requested in the 
petitions. Specifically, NHTSA requested relevant test data, and 
recommendations for other ways to address aerodynamically sloped and 
raised roofs, including changes in the orientation, size, and shape of 
the test plate.

IV. Comments on the Petitions

    A total of 11 comments were received by the agency in response to 
the notice. Five passenger vehicle manufacturers (Ford, General Motors, 
Mercedes-Benz, Volkswagen, and Volvo), a second-stage manufacturer (S & 
S Coach Company), two trade associations (American Automobile 
Manufacturers Association (AAMA) and RVIA), a group of concerned 
citizens, and two safety organizations (Advocates for Highway and Auto 
Safety (Advocates) and MCR/LRI Inc. Liability Research Group (MCR/LRI 
Inc.)) submitted comments. These comments are summarized below, grouped 
according to the similarity of their positions on the issues.

A. Comments on the RVIA Petition and the Suitability of Standard No. 
220 Test Procedures for Raised Roof Vehicles

1. Passenger Vehicle Manufacturers and AAMA
    Ford did not support or oppose the RVIA recommendation, but it did 
comment on the appropriateness of Standard No. 216 and 220 test 
procedures for testing the raised roofs of conversion vans. Ford stated 
that Standard No. 220 may be more practicable for the low volume roof 
modifications addressed by RVIA. In addition, Ford expressed concern 
that van converters who supply vehicles for drivers and passengers with 
disabilities may not be able to certify compliance with Standard No. 
216. According to Ford, the simplified test for school buses in 
Standard No. 220 may make certification more practicable for those 
converters.
    Some commenters suggested that, rather than adopt a separate test 
procedure for raised roof vehicles, the agency could modify the 
Standard No. 216 test procedure to make it more suitable for these 
vehicles. Ford suggested increasing the allowable deflection to reflect 
the added space between the raised roof and occupants in vehicles with 
raised roofs. Volkswagen agreed that raised roof vehicles should be 
tested using Standard No. 216 rather than Standard No. 220. It also 
suggested three different methods for modifying the procedures to 
accommodate raised roof vehicles: (1) test with the raised roof removed 
and the test plate applied to the supporting structure, (2) exclude the 
measured roof crush of the raised roof from the 127 mm (5 inch) 
displacement, and (3) measure the 127 mm (5 inch) displacement into the 
passenger compartment starting from where the test plate reaches the 
inner roof.
2. Second Stage Manufacturers and RVIA
    RVIA commented that several states require Standard No. 220-type 
testing to certify ambulance conversions purchased and licensed by 
their states. They enclosed a November 1, 1994 document from the 
General Services Administration (Federal Specifications for Ambulances, 
KKK-A-1822D) specifying this test for use by all Federal agencies when 
procuring ambulances.

[[Page 8909]]

    In response to the agency's request for data to show that RVIA's 
suggested amendment would not reduce the stringency of the test, and 
that A-pillar strength is retained after the roof is cut out during a 
conversion, RVIA commented that they were in the midst of conducting 
new tests and would submit their results to the docket. The agency has 
not yet received any data from RVIA, but will consider these data if 
and when they become available.
    S&S Coach Company, a final stage manufacturer of funeral coaches, 
submitted a petition for consideration to exclude from Standard No 216 
funeral coaches having a gross vehicle weight rating (GVWR) of 2,722 
kilograms (6000 pounds) or less. They stated that the current test 
procedure makes it impossible to test the front edge of the roof. They 
believe that these vehicles have very little risk of rollover because 
they are produced in small numbers, are primarily in urban use, and 
operate at slow speeds.
3. Safety Advocacy Groups
    MCR/LRI Inc. stated that the petitioners should provide data to 
show the maximum force experienced by the roof in realistic, injury-
producing rollovers in their vehicles. In addition, before any 
amendment is made in the current requirements of Standard No. 216, MCR/
LRI Inc. said that RVIA should provide data to show that the suggested 
amendment does not degrade the rollover safety of their vehicles.
    Advocates stated that the NHTSA should reject RVIA's request for 
exclusion from the test requirements of Standard No. 216. Advocates 
agrees with NHTSA's concerns that compliance before the roof is cut out 
does not necessarily mean that the original roof would still comply 
after modification, and that the Standard No. 220 procedures do not 
assure frontal compartment protection.
    Advocates urged NHTSA to require raised roof vehicles to meet the 
Standard No. 220 requirements, in addition to those of Standard No. 
216, because raised roof vehicles can carry a full complement of 
passengers in the front and rear compartments, necessitating protection 
for both areas.

B. Comments on the Ford Petition, and Test Plate Orientation and Size

1. Passenger Vehicle Manufacturers and AAMA
    Ford buttressed its petition by presenting test results from three 
test facilities with which they contracted to test four 1994 Ford 
Taurus sedans using the current Standard No. 216 test procedure. The 
plate placement was highly variable, resulting in different roof 
strength measurements for each Taurus tested at the different test 
facilities. Data on the variability of plate placement were submitted 
to the docket and Ford stated that it would submit its test results 
after analyzing the data.
    GM, Volvo, and Mercedes-Benz generally supported the amendment 
suggested by Ford to the Standard No. 216 procedure, while Volkswagen 
remained neutral. Although Ford's test procedure does not provide for 
the consistent placement of the plate and the same contact point, GM 
believed that in most cases, the test plate would contact the front 
portion of the roof prior to reaching 127 mm (5 inches) of crush. In 
addition, GM stated that Ford's suggested test plate positioning would 
eliminate an ``edge condition,'' which can result in concentrated 
loading over a small area of the roof.
    There was some disagreement among the manufacturers over whether 
NHTSA should consider changing test plate angles, although they all 
agreed that data would be needed to support such a change. GM suggested 
that, if NHTSA's test procedure is intended to simulate loading in 
rollover crashes, the agency should consider changes in the plate 
angles to accommodate the range of vehicle designs. GM supports a NHTSA 
study of the appropriateness of the current test plate angles.
    Ford opposed changing the test plate size, shape, or angle. Ford 
stated that crash data should be used to verify that any new angles are 
more representative of real-world rollover crashes. Ford also stated 
that the current test plate size adequately represents the ground 
surface contact area in rollover accidents, and reducing that size 
would probably require strengthening of long roofs, due to the more 
concentrated loading.
    Mercedes-Benz also opposed test plate angle changes. Assuming that 
NHTSA might propose higher plate angles, Mercedes-Benz stated that 
changing the direction of the loading might make the test more 
stringent, necessitating a redesign of the roof pillars to respond to 
the more horizontal loading.
    Although it is not directly relevant to its petition, Ford also 
believes some methods used by test facilities to tie-down vehicles pre-
stress the pillars and the roof and reduce the measured roof strength. 
As more data become available, Ford plans to direct the agency's 
attention to further changes needed in the Standard No. 216 test 
procedure.
    AAMA also supported the Ford suggestion, but suggested a slight 
change in the language of Ford's suggested amendment. It thought that 
some persons might misinterpret Ford's phrase ``opening in the body 
structure for the windshield'' to mean the edge of the depression in 
the metal roof panels into which the edge of the windshield is mounted. 
Ford confirmed to the AAMA that it intended to refer to the edge of the 
metal roof panels and windshield, AAMA suggested the following language 
for the test procedure in Standard 216 for S6.2(d):

    The initial contact point, or center of the initial contact 
area, is on the longitudinal centerline of the device. A line normal 
to the lower surface of the test device and through a point on its 
longitudinal centerline and 25 mm rearward of the front edge passes 
through the rear edge of the visible exterior surface of the 
windshield.

    Volkswagen neither supported nor opposed the amendment suggested by 
Ford, because it had experienced no difficulty with the procedures. 
However, it urged that any amendment of Standard No. 216 be flexible 
and not limited in its suitability to test different vehicle roof 
configurations.
    Ford and the AAMA both urged adoption of the Ford suggestion in 
order to achieve harmonization between Standard No. 216 and Transport 
Canada's CMVSS No. 216.
    Five consumers commented that the Ford suggestion would provide 
better protection for all passengers and drivers.
2. Safety Advocacy Groups
    MCR/LRI Inc. stated that the petitioners should submit data to show 
that the force on the roof in their amendment is realistic and that 
there would not be a degradation in the rollover safety of new vehicles 
if the Ford recommendation were accepted.
    MCR/LRI Inc. also stated that minor amendments to Standard No. 216 
are unlikely to achieve an adequate level of roof crush protection. 
Their analysis of 50 rollover accident cases showed that the roof was 
substantially distorted in all cases. They concluded that the head and 
neck injuries almost certainly occurred inside the vehicle as a 
consequence of roof crush. MCR/LRI stated that the current Standard No. 
216 test improperly takes advantage of the strength imparted by the 
windshield, because in virtually all rollovers, the windshield fails, 
resulting in a 75 percent drop in roof strength.
    Instead, MCR/LRI urged NHTSA to require the Standard No. 208, 
Occupant crash protection, rollover test with specific head and neck 
injury criteria,

[[Page 8910]]

and maximum levels of roof intrusion. It suggested compliance be 
demonstrated by a drop test or optionally using head and neck injury 
criteria in a drop test.
    Like MCR/LRI, Advocates thought that the modifications to the 
current Standard No. 216 test procedure would not be sufficient. It 
agreed that a modified angle and smaller test plate may result in a 
more stringent test, but it was not certain that any manipulation of 
the test plate angles would generate the desired result because of the 
radical slope of a number of current roof designs. Advocates also 
stated that there are no data to indicate what forces an A-pillar 
should withstand, and in which direction it should withstand them, in 
real-world crashes.
    Advocates considered the Standard No. 216 test to be outdated and 
inadequate. It was concerned that the proposed modifications will be in 
lieu of a dynamic roof strength test that it believes the agency should 
adopt. In a dynamic rollover test, Advocates asserted that required 
roof loads should be much higher than the 1.5 times unloaded vehicle 
weight now used in the static test, because rollover crashes are known 
to involve much higher loads. Advocates was also concerned that there 
are no criteria governing permissible injury levels associated with the 
test requirements in either Standards 216 or 220.
    Although it was not directly related to the petitions, Advocates 
opposed the exclusion of vehicles between 2,722 and 4,536 kilograms 
(6,000 and 10,000 pounds) GVWR from the purview of this rule. Advocates 
commented that this group includes small school buses, which carry many 
young passengers. Advocates stated that excluding these vehicles is not 
a responsible stance for an agency charged with protecting and 
enhancing public safety in passenger vehicles.

V. NHTSA Research on the Proposed Test Procedure

A. Passenger Cars

    Based on the comments to the notice, the agency decided to test two 
passenger cars using the current Standard No. 216 test procedure, and a 
modified test procedure based on the Ford recommendation. Because the 
Ford Taurus was one of the vehicles mentioned in Ford's petition, it 
was chosen as one of the vehicles to be tested by the agency.
    The other passenger car tested was the Dodge Neon. The Dodge Neon 
had the highest roof slope among approximately 30 passenger cars 
surveyed by the agency. NHTSA concluded that if a revised test 
procedure is suitable for a contoured roof such as that in the Dodge 
Neon, and if it is at least as stringent as the current test procedure, 
then that test would be suitable for all passenger vehicles that are 
currently being produced.
    Both the left and right sides of each vehicle's roof were tested. 
Standard No 216 only requires testing one side of the roof per vehicle, 
so there is a slight possibility that the deformation caused by the 
first test affected the results of the second test. However, the amount 
of roof crush and the area contacted by the test plate were so small 
that NHTSA judged that the integrity of the roof structure on the other 
side of the vehicle was not altered by the first test. NHTSA requests 
comment on this judgment.
    The left side was tested using the current Standard No. 216 test 
plate placement procedure and the right side was tested using a 
modified test plate positioning procedure that moved the plate forward 
until the plate's front edge was vertically flush with the forwardmost 
point of the exterior roof including trim of the windshield (Figure 1 
of the proposed rule). This is a slight modification to the Ford 
suggested procedure in that the test plate is not positioned relative 
to the rearmost windshield opening, but rather to the forwardmost point 
of the exterior roof including trim.
    Although NHTSA used a test plate placement procedure slightly 
different from the one Ford suggested, the agency believes that its 
procedure still addresses Ford's concerns relating to consistent 
placement of the test plate for repeatability and concentrated loading 
when the plate leading edge is behind the leading edge of the roof. 
Placement of the test plate leading edge at the forwardmost point of 
the roof prevents the leading edge of the plate from being placed 
several inches rearward of the A-pillars, where it would penetrate into 
the roof. Under Ford's suggested test plate placement procedure, the 
leading edge of the plate may penetrate the roof if a line connecting 
the rearmost points on either side of the windshield edge of the roof 
is more than 25 mm (1 inch) behind the forwardmost point on the roof, 
which is usually located at the longitudinal centerline of the vehicle.
    The force-deflection curves generated by the current and modified 
test plate placement procedures for the Ford Taurus and Dodge Neon are 
available in the docket. For the Ford Taurus, up to approximately 10 mm 
(0.4 inches) of roof crush, the force does not build up when using the 
current Standard No. 216 test procedure. After this point, the slope of 
the traces (which correlates with roof stiffness) under the two 
procedures are about the same. Once 40 mm (1.57 inches) of crush is 
reached, the modified and current test procedures produce almost 
identical force-deflection results. Total roof deflection was about 54 
mm (2.1 inches) under both the procedures, at 22,240 N (5,000 pounds) 
of applied plate load.
    The results from the Dodge Neon roof crush tests showed almost 
identical force-deflection characteristics in the current and modified 
test procedures up to 46 mm (1.8 inches) of crush. At 46 mm (1.8 
inches), the currently prescribed test procedure reached 1.5 times the 
unloaded vehicle weight of the tested vehicle. Under the modified test 
procedure, the load requirement was reached after about 54 mm (2.1 
inches), indicating a 17 percent increase in the roof crush. The 
required load limits were reached within the specified roof deflection 
limits (127 mm, or 5 inches) for both vehicles, under both the current 
and modified test procedures.
    Roof crush results from the Taurus and Neon vehicles indicate that 
the modified procedure could be adopted by the agency without any 
appreciable reduction in test stringency. NHTSA concludes that the 17 
percent extra crush under the modified test procedure on the Dodge Neon 
is not appreciable because it represents a displacement of only 8 mm 
(0.3 inches), but requests comment on this assessment. The modified 
test procedure would alleviate the ambiguous language in current 
Standard No. 216, and it would position the test plate more 
consistently.

B. Raised Roof Converted Van Tests

    To compare the stringency of the Standard Nos. 216 and 220 roof 
crush procedures when applied to raised roof vehicles, the agency 
tested a 1992 Chevy Astro Van with a raised roof in accordance with the 
modified Standard No. 216 test procedure, and compared the test results 
with the test results of an altered 1994 GMC Safari van tested in 
accordance with Standard No. 220 test procedures. The agency obtained 
the Safari Van test data from a test report produced by General Testing 
Laboratories, Inc., for Mark III Industries. Although the two vehicles 
were not identical, they are both ``L/M'' class vans produced by GM and 
the raised roofs in each were very similar in style. The roofs were cut 
out behind the B-pillar. This, according to a RVIA representative, is 
the predominant method used by alterers in converting vans to 
recreational vehicles. This method is preferred because the roof bows 
are not removed at the B-pillar,

[[Page 8911]]

thus helping to retain the roof support over the front occupant 
compartment.
    For purposes of the modified test, the roof over the front occupant 
compartment was defined as the roof area between a transverse vertical 
plane passing through a point 162 mm (6.4 inches) rearward of the 
seating reference point (SgRP) of the driver seat and a transverse 
vertical plane passing through the forwardmost point on the roof 
including trim. NHTSA requests comment on the appropriateness of this 
definition.
    The data from the 1994 GMC Safari van showed the force and 
deflection of the roof at an applied load 1.5 times the unloaded 
vehicle weight in a Standard No. 220 type test (the test report is 
available in the docket). The test plate covered the entire roof and 
was controlled by 4 hydraulic rams, one at each corner. The initially 
horizontal plate was lowered until the plate contacted the roof at two 
points. A load was applied. When 1.5 times the unloaded vehicle weight 
was reached, the maximum deflection was 51 mm (2 inches) at the left 
front corner of the test plate. Standard No. 220 specifies a maximum 
deflection of 130 mm (5.12 inches).
    The agency conducted its own test using a modified Standard No. 216 
test procedure and recorded the force-deflection characteristics on a 
1992 Chevy Astro van with a raised roof very similar to the 1994 Safari 
van tested using the Standard No. 220 procedure. The test report for 
the test conducted by NHTSA is also available in the docket. The test 
plate was oriented in the same manner as in passenger car tests using 
the modified test procedure (forward edge of the plate flush with the 
forwardmost exterior roof point along the longitudinal centerline of 
the vehicle). The test plate loaded the roof initially at the highest 
point on the raised roof, which was behind the B-pillar and above the 
original roof by about 178 mm (7 inches). Roof crush was continued for 
approximately 533 mm (21 inches) of crush, recording the force-
deflection characteristics over that entire distance.
    The force-deflection trace from the modified Standard No. 216 test 
(available in the docket) shows that 1.5 times the unloaded vehicle 
weight was reached after 51 mm (2 inches) of roof crush at the initial 
point of contact. After an additional 51 mm of roof crush, the roof was 
loaded through other contact points forward of the initial point of 
contact. The crushing of the roof continued until the plate contacted 
another point on the roof over the front occupant compartment. This 
trace shows the force vs. displacement curve for the entire crushing 
sequence of the roof. After a total crush of approximately 173 mm (6.8 
inches), the plate reached the original roof structure prior to 
conversion, and the load at that point was 35,000 N (7,870 pounds). The 
force peaked at 45,000 N (10,120 pounds) when the total roof crush was 
about 211 mm (8.3 inches), and then force level dropped to about 42,000 
N (9,450 pounds) as the roof was crushed to 285 mm (11.2 inches).
    The results of the Standard No. 216 and Standard No. 220 tests were 
then compared to determine whether the Standard No. 220 test was as 
stringent as the Standard No. 216 procedure and tested the appropriate 
areas of the roof for proper crush strength. Both vehicles reached 1.5 
times the unloaded vehicle weight at approximately 51 mm (2 inches) 
roof crush.
    The raised roof reached a higher test load (30,700 N, or 6,900 
pounds, compared to 26,700 N, or 6,000 pounds) with less crush of the 
roof during the Standard No. 220 type test mainly because of the 
difference in the area of contact between the roof and the test plate 
in the two test procedures. The test plate load in the Standard No. 220 
test procedure was distributed over a larger roof area and thus 
enlisted more support pillars in developing the load. Moreover, the 
test did not preferentially crush the roof over the front occupant 
compartment.
    Therefore, the Standard No. 220 test procedure appears to be 
slightly less stringent than the procedure in Standard No. 216. A 
similar raised roof developed a higher load under the Standard No. 220 
procedure than under the Standard No. 216 procedure. Therefore, because 
the load requirements are essentially the same under the two test 
procedures, a roof would more easily sustain load and pass the test 
under the Standard No. 220 procedure. The Standard No. 220 test also 
does not test the integrity of the front roof structure as well as 
Standard No. 216, which concentrates on the roof over the front seat 
occupants.

VI. Agency Response to the Comments

A. Issues Related to the RVIA Petition

    The agency does not consider the Standard No. 220 test easier to 
administer than the Standard No 216 test, as posited by Ford. Moreover, 
the total cost for a Standard No. 220 test is slightly higher than that 
for a Standard No. 216 test. Therefore, the agency disagrees with 
Ford's rationale for using the Standard No. 220 test procedure.
    The agency has examined the applicability of the Standard No. 220 
test procedure for roof crush resistance of raised roof vehicles. 
Standard No. 220 and 216 test results were compared to determine the 
applicability of a 220-type test. Results reveal that a 220-type test 
will be less stringent when compared to the Standard No. 216 test when 
the test plate is positioned to apply the load over the front occupant 
compartment.
    Volkswagen's and Ford's suggestion for excluding the crushing of 
the raised roof portion from the 127 mm (5 inch) limitation in the 
standard was investigated by the agency, as detailed in the van tests 
above. NHTSA concluded that, if the plate is placed over the front 
occupant compartment and A-pillar, where roof integrity is most 
important, the proposed test criteria could be considered as stringent 
(in terms of providing the same level of occupant safety) as the 
current test criteria. Therefore, the agency tentatively agrees with 
Ford and Volkswagen that allowable roof crush for added-on roofs under 
Standard No. 216 could be increased to reflect the added space between 
the original roof and the raised roof.
    Unfortunately, NHTSA can see no practical way to determine the pre-
alteration position of the original roof. The original roof is no 
longer present, so no measurements can be made between it and the 
added-on roof. In addition, the original roof may have compound curves, 
making the precise determination of its former location relative to the 
initial contact point on the added-on roof difficult. Although NHTSA is 
not proposing to modify the test procedure to account for it at this 
time, the agency specifically requests comment on possible methods for 
taking this increased head room into account. If the commenters suggest 
a suitable method, NHTSA may include such a modification in the final 
rule. NHTSA also requests comment on how or whether the test procedure 
should address the tinted glass panels, or sunroofs that some vehicles 
have over the front occupant compartment.
    The agency disagrees with S&S Coach Company that funeral coaches 
should be excluded from normal Standard No. 216-type testing. The 
agency believes that these vehicles are driven at a normal range of 
speeds most of the time and could be exposed to the risk of rollover, 
just as other passenger vehicles on the highway. Since some of these 
vehicles have raised roofs, they would be subject to the amended test 
procedure used for raised roof vans. However, the load requirements 
would

[[Page 8912]]

be the same as for unmodified vehicles, whether passenger cars, multi-
purpose passenger vehicles, trucks, or buses.
    Although the agency would welcome data on roof loads experienced by 
vehicles in ``realistic, injury-producing rollovers'', which MCR/LRI 
suggested was necessary, NHTSA is not aware of any such data. NHTSA 
believes that such data would be difficult if not impossible to 
generate because, due to the inherent complexity of rollovers and 
injury causation, it is difficult to determine precisely the role of 
roof crush in causing head/neck injury.

B. Issues Related to the Ford Petition

    Regarding Ford and the AAMA's request that NHTSA consider 
harmonization of the roof crush standard, NHTSA does not believe that 
is an appropriate step at this time. There is no UN/ECE equivalent with 
which NHTSA can harmonize. Further, the Canadian CMVSS No. 216's 
reference to ``the left front or the right front portion of the 
vehicle's roof structure'' is not sufficiently specific to meet the 
objectivity requirements that apply to all FMVSSs. It would also not 
provide the repeatability that Ford desires.
    NHTSA already tests with roof racks removed, as Ford suggested in 
its petition. In a September 21, 1992 interpretation letter, NHTSA 
stated that the agency would conduct its compliance testing for 
Standard No. 216 with roof-mounted accessories such as roof racks 
removed, because the purpose of the test is to measure the strength of 
the roof, not the strength of roof mounted accessories. Further, 
conducting the test with roof mounted accessories in place could 
influence the positioning of the test device. Although this issue has 
been addressed by interpretation, NHTSA is adding a sentence to the 
regulatory text to make it explicit in the CFR.
    GM urged that the agency conduct a study to determine the 
appropriateness of the current test plate angles. Preliminary studies 
have been conducted by the agency with an alternative plate angle of 
zero degrees with respect to the longitudinal axis and fifteen degrees 
with respect to the lateral axis of the plate. However, these studies 
do not provide a sufficient basis for modifying the plate angle or size 
requirements in the test procedures.
    The agency welcomes any data Ford submits on pre-stressing of the 
A-pillar and roof due to the tie-down method used in Standard No. 216. 
However, since Ford is not sure that the tie-down method is a problem 
and no other manufacturer has brought the matter to the agency's 
attention, the agency will not pursue this matter until Ford submits 
more data. NHTSA notes that modification of the tie-down method, if 
necessary, can probably be addressed by a change in the compliance test 
procedure and would not require an amendment to the standard.
    Regarding Mercedes-Benz's contention that the plate angles should 
not change, the agency agrees that a test with a higher plate angle 
would be more stringent because it would stress the A-pillar in a more 
lateral direction. However, without changing the plate angles or size, 
the initial contact point will not change. If the initial contact point 
is too far behind the A-pillar, the load will be transferred primarily 
through the B-pillar, instead of the A-pillar, and thus not test roof 
strength in the area over the front occupant compartment. Nevertheless, 
the agency is taking the conservative approach of not proposing changes 
in test plate angles at this time because it prefers to accumulate more 
data on the effect of different plate angles. Until these data are 
developed by or supplied to the agency, the agency will defer proposing 
modifications of the load limits and plate angles and sizes. NHTSA 
requests any available data on this subject.
    NHTSA agrees with Volkswagen's suggestion that any amendment of 
Standard No. 216 be flexible and applicable to different vehicle roof 
configurations. It is always the intent of the agency to develop test 
procedures for its rules that are uniformly applicable to all vehicles, 
irrespective of their design configuration.
    NHTSA agrees with MCR/LRI Inc. that there should be some data 
showing that the Ford recommendation does not reduce the stringency of 
the regulatory requirements. In order to assure that the stringency of 
the standard is maintained, the agency conducted comparison tests using 
the current test procedure and the proposed test procedure.
    Like MCR/LRI, the agency is concerned about rollover safety and 
head and neck injuries resulting from roof crush. However, NHTSA 
questions whether the head/neck injuries in MCR/LRI's case study of 50 
rollover crashes are solely caused by excessive roof crush. Correlation 
of roof distortion with injury is not sufficient evidence to conclude 
that reduced roof intrusion alone would have prevented head/neck 
injuries.
    The agency disagrees with MCR/LRI's contention that the current 
Standard No. 216 test improperly takes advantage of the strength 
imparted by the windshield. NHTSA recognizes that the windshield is, 
for engineering purposes, an integral part of the structures that 
manufacturers use to strengthen the roof. In view of this, the 
windshield should not be separated from the roof greenhouse structure 
during a roof crush test. While the windshields failed in the very 
severe rollover crashes selected by MCR/LRI, resulting in diminished 
roof crush resistance, the agency does not agree that the test 
procedure should reflect these unusually severe rollover crashes. All 
of the crashes that MCI/LRI selected resulted in serious to fatal head 
or neck injuries, while less than five percent of non-ejected occupants 
in all rollover crashes receive such injuries. The windshield probably 
contributes to roof crush resistance in more representative, less 
severe, rollover crashes, and the strength it imparts should be counted 
in the consistent minimum level of roof strength that the standard 
ensures.
    The agency agrees with Advocates and MCR/LRI that it has not found 
sufficient data to propose a different plate angle and size for all 
vehicles at present. However, Standard No. 216's compliance test data 
show that roof contact area is generally very small, especially for 
late model year vehicles. The table ``FMVSS 216 Data Compilation'' in 
the docket shows that in most cases less than 100 square inches of roof 
are crushed. In view of this, a smaller test plate would be sufficient 
for roof crush testing of a majority of production vehicles. NHTSA 
requests comment on this issue, and specifically on the size of the 
small test plate.
    The agency is not planning an upgrade of Standard No. 216 to a 
dynamic test at this time. Instead, this rulemaking is only amending 
Standard No. 216 test procedure to the extent necessary to remove the 
ambiguity of test plate placement for testing and the controversy of 
testing raised roof vehicles, while maintaining the stringency of the 
current test requirement. NHTSA would welcome any submissions of data 
supporting an upgrade of Standard No. 216 to include a dynamic test 
procedure and/or to include a rollover injury criteria. However, the 
agency is not planning to make them a part of this rulemaking.
    NHTSA disagrees with Advocates that there is any gap in its safety 
standards concerning rollover safety for school buses. Standard No. 
220's roof crush requirements apply to all school buses, even those 
between 2,722 and 4,536 kilograms (6,000 and 10,000 pounds). Therefore, 
these vehicles, by virtue of their intended purpose, are covered by the 
appropriate roof crush requirements. Further, the agency is also not

[[Page 8913]]

convinced that the safety problem due to roof crush in vehicles which 
have a GVWR rating above 2,722 kilograms (6,000 pounds) necessitates 
any change in Standard No. 216 at this time.

VII. Proposed Test Procedure and Requirements

A. Description of Proposal

    NHTSA is proposing to modify the test plate size and placement to 
fulfill the original intent underlying Standard No. 216, and reduce 
test variability. A summary of the proposed changes to the requirements 
and test procedures follows:
    (1) For all vehicles without raised roof structures, the 
requirements and test procedures would remain the same, except that the 
initial placement of the leading edge of the test plate would be flush 
with the forwardmost edge of the roof. This change would ensure 
engagement of the A-pillars.
    (2) For vehicles with a raised or altered roof, the test plate size 
might vary depending upon the position of the raised roof relative to 
the front occupant compartment. The current large test plate would be 
placed in position with its lower surface touching the initial contact 
point. If the initial contact point is on any portion of raised or 
altered roof rearward of the front occupant compartment, then a small 
test plate (610 mm by 610 mm, or 24 inches by 24 inches) is used for 
testing instead. Because the 5 degree plate angle is so low, initial 
contact of a large test plate with the raised roof to the rear of the 
front occupant compartment would be most likely to occur on vehicles 
whose raised or altered roof is completely located to the rear of the 
front occupant compartment. The performance requirement would be the 
same as when testing with the large test plate. The small test plate 
would have to reach a load of 1.5 times the unloaded vehicle weight 
within 127 mm (5 inches) of displacement.
    A small test plate is needed in this particular situation to assure 
that the roof over the front occupant compartment in the area of the A-
pillars is tested. Otherwise, the large plate might test only the roof 
to the rear of the front occupant compartment. In addition, NHTSA wants 
to make sure that the roof modification process does not significantly 
affect the original strength of the front roof structure. Therefore, it 
would be appropriate to use a smaller test plate to evaluate only the 
front roof strength for vehicles (mostly van conversions) where the 
roof to the rear of the front occupant compartment may have been 
compromised during the conversion. Conversely, it would be appropriate 
to test a raised roof which is located, in part, over the front 
occupant compartment, even if some raised roof to the rear were also 
subsequently crushed.
    The size of the smaller plate must be large enough so that the 
plate edges do not penetrate the roof. Based on its measurement of nine 
late model year minivans, NHTSA believes that a test plate of 610 mm by 
610 mm (24 inches by 24 inches) would be sufficient. In nearly all the 
tests, a much smaller area than the size of the proposed small plate 
was crushed (see Table ``FMVSS 216 Data Compilation,'' in the docket). 
However, the agency is not proposing to use a smaller plate for all 
tests because it does not have sufficient data to determine the 
appropriateness of a smaller test plate for all roof crush tests. NHTSA 
requests comment on whether the proposed plate size is appropriate.

B. Explanation of NHTSA's Selection of the Proposed Test Procedure and 
Requirements

    Because the agency's testing indicates that the Standard No. 220 
test procedure is less stringent than the modified Standard No. 216 
test procedure, NHTSA did not adopt RVIA's recommendation to use it. 
Nevertheless, NHTSA believes that using the modified Standard No. 216 
test procedure for testing conversion vans and other such vehicles 
would address RVIA's and Ford's concerns. The use of the modified 
procedure also accommodates the belief expressed by the safety groups 
that the roof strength should not be degraded when part of the roof is 
cut out and replaced by a raised roof.
    Ford's main concern is the variability in the initial contact point 
inherent in existing test procedures in Standard No. 216. Because of 
the five degree angle of the larger plate, some vehicles with 
aerodynamic roof designs could have an initial contact point with the 
test plate rearward of the A-pillar area, even though the original 
intent underlying the standard was to test the roof area in the 
vicinity of the joint of the A-pillar and front header and side rail 
components.
    This concern would be partly addressed by the modified Standard No. 
216 procedure. By consistently placing the forward edge of the test 
plate flush with the forwardmost edge of the roof, the leading edge of 
the plate would not penetrate into the softer parts of the roof, but 
would be aligned with the supports for the front occupant compartment. 
This should assure engagement of the A-pillar in most cases. On some 
vehicles with highly curved roofs, the initial contact point could 
still be behind and inboard of the A-pillar area, but at least the 
plate will contact the A-pillar area after the roof has been depressed 
a short distance.
    However, by itself, realigning the plate would not be sufficient to 
address RVIA's concern and ensure engagement of the appropriate area on 
all raised roof vehicles. This is because a raised roof may be so high 
that the A-pillar area would never be engaged before the permissible 
plate travel is reached. Therefore, NHTSA is proposing to adopt a 
smaller test plate (610 mm by 610 mm, or 24 inches by 24 inches) for 
use with vehicles which have altered/raised roof structures located 
rearward of the front passenger compartment that would make initial 
contact with the current test plate. This would assure that, for most 
vehicles, the test plate would contact the front roof only. The choice 
of test plate is based on whether initial contact is with the roof over 
the front occupant compartment.

VIII. Changes to the Regulatory Text

    Substantial changes to the regulatory text are being proposed, 
although the substance of the regulation remains largely the same. To 
accommodate the insertion of a definitions paragraph (customarily 
located at the beginning of NHTSA's standards), all subsequent 
paragraphs, i.e., those beginning with S4, would need to be renumbered. 
S4 (former ``requirements'') would become S5. S5 (former ``test 
device'') would become S6. S6 (former ``test procedure'') and all of 
its subparagraphs would become S7 and subparagraphs. The definitions 
paragraph would be designated S4. By better segregating the 
requirements and the test procedures between S5 and S7, it is possible 
to eliminate the redundant statement of parallel test procedures under 
the former S6.3. Figure 1 would be revised to reflect the new plate 
positioning procedure.
    In addition, a number of clarifying minor changes were made to the 
regulatory text. A sentence was added to the test procedures to 
explicitly specify that non-structural components such as roof racks 
would be removed prior to testing. This was already the agency's 
interpretation of the current test procedure.

IX. Proposed Lead Time

    The proposed amendments to Standard No. 216 are not likely to 
impose any additional costs on vehicle manufacturers and converters, 
although NHTSA requests comments on this issue. The amended test 
procedures

[[Page 8914]]

provide for repeatable testing that follows the original intent of the 
standard. For most vehicles, the test would be essentially the same as 
it is now. Even for those vehicles for which use of a smaller test 
plate would be specified, the same or similar equipment is used for 
testing.
    The agency is not proposing the five year lead time requested by 
Ford. This action is being taken at Ford's request and, to the extent 
that test plate placement differs from the current procedures, it 
should make compliance with the standard easier for all vehicles, since 
engagement of the A-pillars is assured.
    Consequently, the amended rule would become effective, and 
compliance would be required, on 180 days following the publication of 
the final rule. However, manufacturers may voluntarily comply with this 
rule earlier.

X. Rulemaking Analyses and Notices

A. Executive Order 12866 and DOT Regulatory Policies and Procedures

    This rulemaking document was not reviewed under E.O. 12866, 
``Regulatory Planning and Review.'' This action has been determined to 
be ``non-significant'' under the Department of Transportation's 
regulatory policies and procedures. The proposed amendments would not 
impose any new requirements but simply clarify existing test procedures 
and allow them to be applied consistently to the intended area of the 
roof on all vehicles. Therefore, the impacts of the proposed amendments 
would be so minor that a full regulatory evaluation is not required.

B. Regulatory Flexibility Act

    NHTSA has also considered the impacts of this notice under the 
Regulatory Flexibility Act. I certify that this proposed rule would not 
have a significant economic impact on a substantial number of small 
entities. As explained above, the rule would not impose any new 
requirements but would instead clarify the test procedures and allow 
them to be applied to the areas of the roof to which they were 
originally intended. It would not have any effect on the price of new 
vehicles purchased by small entities.

C. Paperwork Reduction Act

    In accordance with the Paperwork Reduction Act of 1980 (P.L. 96-
511), there are no requirements for information collection associated 
with this proposed rule.

D. Executive Order 12612 (Federalism)

    NHTSA has analyzed this proposal in accordance with the principles 
and criteria contained in E.O. 12612, and has determined that this 
proposed rule would not have sufficient federalism implications to 
warrant the preparation of a Federalism Assessment.

E. Civil Justice Reform

    This proposed rule would not have any retroactive effect. Under 49 
U.S.C. 30103, 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, except to the extent that the state requirement imposes a 
higher level of performance and applies only to vehicles procured for 
the State's use. 49 U.S.C. 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.

XI. Submission of Comments

    Interested persons are invited to submit comments on the proposal. 
It is requested but not required that 10 copies be submitted.
    Comments must not exceed 15 pages in length (See 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 forth 
the information specified in the agency's confidential business 
information regulation. See 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 for inspection in the docket. The 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.

List of Subjects in 49 CFR Part 571

    Imports, Motor vehicle safety, Motor vehicles.

    In consideration of the foregoing, it is proposed that 49 CFR Part 
571 be amended as follows:

PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS

    1. The authority citation for Part 571 of Title 49 would continue 
to read as follows:

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

    2. Section 571.216 would be amended as follows:
    a. S4 is revised.
    b. S5 is revised.
    c. S6 is revised, and S6.1, S6.2, 6.3 and S6.4 are removed.
    d. S7, S7.1, S7.2, S7.3, and S7.4 are added.
    e. Figure 1 at the end of the section is revised.
    The additions and revisions would read as follows:


Sec. 571.216  Standard No. 216; roof crush resistance

* * * * *
    S4. Definitions.
    Altered roof means a roof that has had all or part of the original 
roof removed and replaced by a roof that is higher than the original 
roof.
    Raised roof means, with respect to a roof which includes an area 
that protrudes above the surrounding exterior roof surface, that 
protruding area of roof.
    Roof over the front occupant compartment means the roof area 
between a transverse vertical plane passing through a point 162 mm 
rearward of the SgRP of the designated

[[Page 8915]]

left front outboard seating position and a transverse vertical plane 
passing through the forwardmost point on the exterior surface of the 
roof, including trim, that lies in the longitudinal vertical plane 
passing through the vehicle's longitudinal centerline.
    S5. Requirements.
    (a) Passenger Cars. Passenger cars shall meet the requirements of 
this paragraph. When the larger test device, described in S6, is used 
to apply a force in Newtons equal to 1.5 times the unloaded vehicle 
weight of the vehicle, measured in kilograms and multiplied by 9.8 or 
22,240 Newtons, whichever produces the lower force, to either side of 
the forward edge of a vehicle's roof in accordance with the procedures 
of S7, the test device shall not move more than 127 millimeters, 
measured in accordance with S7.4. Both the left and right front 
portions of the vehicle's roof structure shall be capable of meeting 
the requirements, but a particular vehicle need not meet further 
requirements after being tested at one location.
    (b) Multipurpose passenger vehicles, trucks, and buses with a GVWR 
of 2,722 kilograms or less that do not have raised or altered roofs. 
Multipurpose passenger vehicles, trucks, and buses with a GVWR of 2,722 
kilograms or less that do not have raised or altered roofs shall meet 
the requirements of this paragraph. When the larger test device, 
described in S6, is used to apply a force in Newtons equal to 1.5 times 
the unloaded vehicle weight, measured in kilograms and multiplied by 
9.8, to either side of the forward edge of a vehicle's roof in 
accordance with the procedures of S7, the test device shall not move 
more than 127 mm, measured in accordance with S7.4. Both the left and 
right front portions of the vehicle's roof structure shall be capable 
of meeting the requirements, but a particular vehicle need not meet 
further requirements after being tested at one location.
    (c) Multipurpose passenger vehicles, trucks and buses with a GVWR 
of 2,722 kilograms or less that have raised roofs or altered roofs.
    (1) Multipurpose passenger vehicles, trucks and buses with a GVWR 
of 2,722 kilograms or less having raised roofs or altered roofs shall 
meet the requirements of this paragraph. When the larger test device 
(or the smaller test device, when specified by paragraph (c)(2)), 
described in S6, is used to apply a force in Newtons equal to 1.5 times 
the unloaded vehicle weight of the vehicle, measured in kilograms and 
multiplied by 9.8, to either side of the forward edge of a vehicle's 
roof, in accordance with the procedures of S7, the device shall not 
move more than 127 millimeters, measured in accordance with S7.4. Both 
the left and right front portions of the vehicle's roof structure shall 
be capable of meeting the requirements, but a particular vehicle need 
not meet further requirements after being tested at one location.
    (2) For vehicles on which the initial contact point of the larger 
test device, when oriented as specified in paragraph S7.2, is with the 
raised roof to the rear of the front occupant compartment, the smaller 
test device described in S6 is used for testing instead of the larger 
test device.
    S6. Test device. The larger test device is a rigid unyielding block 
with its lower surface formed as a flat rectangle 762 millimeters by 
1,829 millimeters. The smaller test device is a rigid unyielding block 
with its lower surface formed as a flat square 610 millimeters by 610 
millimeters.
    S7. Test procedure. Each vehicle shall be capable of meeting the 
requirements of S5 when tested in accordance with the following 
procedure.
    S7.1 Place the sills or the chassis frame of the vehicle on a rigid 
horizontal surface, fix the vehicle rigidly in position, close all 
windows, close and lock all doors, and secure any convertible top or 
removable roof structure in place over the passenger compartment. 
Remove roof racks or other non-structural components.
    S7.2 Orient the test device as shown in Figure 1, so that--
    (a) Its longitudinal axis is at a forward angle (in side view) of 
5 deg. below the horizontal, and parallel to the vertical plane through 
the vehicle's longitudinal centerline;
    (b) Its transverse axis is at an outboard angle, in the front view 
projection, of 25 deg. below the horizontal (note: if using the smaller 
test device, the longitudinal and transverse axes will be of the same 
length);
    (c) Its lower surface is tangent to the surface of the vehicle;
    (d) The initial contact point, or center of the initial contact 
area, is on the longitudinal centerline of the lower surface of the 
test device; and
    (e) The midpoint of the forward edge of the lower surface of the 
test device is tangent to the transverse vertical plane passing through 
the forwardmost point on the exterior surface of the roof, including 
trim, that lies in the longitudinal vertical plane passing through the 
vehicle's longitudinal centerline.
    S7.3 Apply force so that the test device moves in a downward 
direction perpendicular to the lower surface of the test device at a 
rate of not more than 13 millimeters per second until reaching the 
force level specified in S5. Complete the test within 120 seconds. 
Guide the test device so that throughout the test it moves, without 
rotation, in a straight line with its lower surface oriented as 
specified in S7.2(a) through S7.2(b).
    S7.4 Measure the distance that the test device moved, i.e., the 
distance between the original location of the lower surface of the test 
device and its location as the force level specified in S5 is reached.

BILLING CODE 4910-59-P

[[Page 8916]]

[GRAPHIC] [TIFF OMITTED] TP27FE97.011


    Issued on: February 21, 1997.
James Hackney,
Director, Office of Crashworthiness Standards.
[FR Doc. 97-4762 Filed 2-26-97; 8:45 am]
BILLING CODE 4910-59-C