[Federal Register Volume 61, Number 49 (Tuesday, March 12, 1996)]
[Notices]
[Pages 10059-10061]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-5801]
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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
Denial of Petition for a Defect Investigation
This notice sets forth the reason for the denial of a petition
submitted to the National Highway Traffic Safety Administration (NHTSA)
under 49 U.S.C. Sec. 30162(a)(2) (formerly section 124 of the National
Traffic and Motor Vehicle Safety Act of 1966, as amended).
By letter dated July 26, 1995, R. David Pittle, Ph.D., Vice
President and Technical Director of Consumers Union (CU), petitioned
the Administrator of the National Highway Traffic Safety Administration
(NHTSA) to investigate the Century Model 590 child safety seat. Dr.
Pittle's request was based on testing conducted for CU by an
independent testing facility that utilized the 20-pound test dummy
included in the test
[[Page 10060]]
procedure for Federal Motor Vehicle Safety Standard (FMVSS) No. 213,
``Child Restraint Systems,'' that is currently scheduled to take effect
in September 1996. This report responds only to that portion of Dr.
Pittle's letter which petitioned the National Highway Traffic Safety
Administration (NHTSA) to begin an investigation to determine whether a
product defect recall of the Century Model 590 should be instituted
under the provisions of 49 CFR Part 577. Those issues concerning CU's
petition seeking amendments to FMVSS No. 213 will be responded to
separately.
Century was the first manufacturer to develop an infant/child
restraint that snaps into a base that can be left in the car. The seat,
the Model 590, was introduced in 1992. The seat base is secured to the
vehicle seat with the vehicle seat belt and does not need to be
unstrapped each time the child seat is removed from the vehicle. The
Century 590 is designed to be used only in a rearward facing position
by children less than 20 pounds in weight.
The Century 590 seat base fractured in three CU tests when used in
the rearward facing position with the seat snapped into the base, where
it is held by two spring-loaded latching pawls. This method of using
the seat is preferred by many parents, as it is a much faster and more
convenient method of placing the child seat into the vehicle compared
to fastening and unfastening the vehicle seat belt. The seat can also
be used without the provided base, by securing it directly to the
vehicle with the seat belts. When secured in this manner, the seat
successfully completed all the crash tests conducted for CU. The seat
portion is equipped with a handle, so that the infant can be carried in
the seat to and from the vehicle.
Under S7.1 of FMVSS No. 213 as currently in effect, a seat that is
recommended by its manufacturer for use by children up to 20 pounds is
tested in the rearward facing position in a 30 mph dynamic test using a
``six-month-old'' dummy that weighs 17 pounds. Among many performance
requirements, S5.1.1(a) provides that the seat must ``[e]xhibit no
complete separation of any load bearing structural element . . . .'' In
addition, pursuant to S5.1.4, ``. . . the angle between the system's
back support surface for the child and the vertical shall not exceed 70
degrees.''
During a FMVSS No. 213 test, the child restraint is secured with a
conventional seat belt to a standard specified passenger seat, which is
mounted on a dynamic test sled. The sled is subjected to an
acceleration equivalent to that experienced in a typical 30 mph frontal
vehicle crash. This acceleration is commonly measured in units of g,
each of which is equal to 32.174 feet per second squared (i.e., the
acceleration of gravity). The shape of the curve depicting the g's over
time during a dynamic test is referred to as the acceleration ``pulse''
of the sled.
S6 of FMVSS No. 213 specifies the velocity change and acceleration
conditions for dynamic tests of child restraints. The velocity change
shall be 30 mph with the acceleration of the test sled entirely within
the curve shown in figure 2 of the FMVSS No. 213.
Depending on the type of sled and how the sled is calibrated, the
magnitude of the peak acceleration and the duration of time the seat is
subjected to the acceleration can vary. Even though the pulse
differences in various sleds are usually very small and are recorded in
increments of milliseconds (1/1,000 of a second), they can produce
significantly different results. If a particular sled subjects the seat
to higher peak g's or if the duration of time that g's are sustained is
longer than that specified in FMVSS No. 213, then the sled test is
considered to be a more ``severe'' test than that specified in FMVSS
No. 213.
FMVSS No. 213 has been revised, and the revised requirements are
currently scheduled to take effect on September 1, 1996 (petitions for
reconsideration are currently pending). Under the revised version of
S7.1, a seat that is recommended by its manufacturer for use by
children in a range up to 10 kg (22 pounds) is tested with a
``newborn'' test dummy (7.5 pounds) and a 9-month-old test dummy (20-
pounds).
The petitioner reported that when it tested Century Model 590 seats
in the rearward-facing position with a 20-pound dummy at a speed of
very slightly over 30 mph, with the seat mounted on the seat base,
three of the seats tested exhibited fractures. In all three cases the
base for the seat, which was belted onto the test sled with a
conventional seat belt, fractured and the seat, which contained the
dummy, was released from the base on one or both sides. This could
create a serious problem, because in an actual collision the portion of
the child restraint that holds the child could impact unfriendly
portions of the vehicle's interior or allow the child to be ejected
from the vehicle.
Century submitted numerous test results, the majority of which were
characterized as tests on ``Experimental'' seats. In some of the tests,
a 17-pound dummy was used, although most used a 20-pound dummy. In the
majority of the tests submitted, the seats passed FMVSS No. 213
requirements, although there were isolated failures.
One 1994 Model 590 seat was tested by the NHTSA Vehicle Research
and Test Center (VRTC) in Marysville, Ohio, using a 17-pound dummy.
Later tests also using a 17-pound dummy were conducted for NHTSA by
Calspan Advanced Technology Center (Calspan), Buffalo, N.Y. In the test
conducted in Marysville, Ohio (VRTC Test RCU-01--September 18, 1995)
the base fractured on the right side and the seat back deflected more
than the 70 degrees specified by FMVSS No. 213. However, the
acceleration pulse curve fell slightly outside the pulse limits
described in FMVSS No. 213.
Later tests of two seats conducted for NHTSA at Calspan (December
12, 1995) resulted in both seats passing the requirements of FMVSS No.
213. (Unlike the September 18, 1995 tests, these were conducted in
accordance with all FMVSS No. 213 test procedures.)
Century reported that it had received no owner reports of failure
in which the base cracked and a ``catastrophic separation'' of the
safety seat from the base occurred. According to Century, this is the
type of failure alleged in the CU petition. Century did, however,
provide reports from owners and users of the subject seat who allege
the seat separated from the base in collision situations.
NHTSA has reviewed all reported cases of the safety seat separating
from the base, including those where the base fractured and those where
the base released without fracture. NHTSA has received 9 reports of the
Century seat separating from the base in collision situations. Century
reported 7 additional incidents, although Century maintains these
incidents are not identical to the CU test failures. Of these 16
reports, it is alleged that the base fractured in at least 5 of the
collisions. In the other eleven collision reports, no information is
included as to whether the base fractured or not. In 8 of the 16
reports, the separation of the seat from the base occurred when the
vehicle was struck on the side.
In its petition, CU provided the agency with data indicating that
the Century Model 590 seat may separate from its base when the
acceleration or dummy weight exceeds the specifications of FMVSS No.
213. However, the seat successfully passed the tests that were
conducted in strict conformance with the test procedures of FMVSS No.
213. It should be pointed
[[Page 10061]]
out that a review of tests involving the Century Model 590, in
particular the VRTC test of September 18, 1995, suggests that the
performance of some seats manufactured in 1994 may be marginal.
When a safety standard establishes minimum performance requirements
for motor vehicles or items of motor vehicle equipment through the use
of specific values for particular parameters, as is the case here,
NHTSA does not consider performance failures at higher levels to, in
themselves, demonstrate that a safety-related defect exists. Moreover,
NHTSA has consistently taken the position that the fact that a vehicle
or item of equipment would not comply with a newly-issued, more
stringent safety standard, which was not in effect on the date the
vehicle or equipment was manufactured, does not constitute evidence
that the vehicle or equipment is defective. Thus, given the fact that
the Century Model 590 appears to satisfy the performance requirements
of FMVSS No. 213 when tested with a 17-pound test dummy utilizing a
conforming acceleration pulse, its performance with heavier dummies or
at higher test speeds and accelerations does not indicate the existence
of a safety defect.
In consideration of the available information, there is no
reasonable possibility that an order concerning the notification and
remedy of a safety-related defect based on the petitioner's allegations
would be issued at the conclusion of an investigation. Therefore, the
petition has been denied. However, the information developed regarding
the reported failures of Century Model 590 seats in actual vehicle
collisions merits further analysis. NHTSA will, therefore, initiate a
Preliminary Evaluation to further investigate the actual collision
performance of this seat in side impact crashes, which are not covered
by FMVSS No. 213 or any other Federal motor vehicle safety standard.
Authority: 49 U.S.C. 30162(a); delegations of authority at 49
CFR 1.50 and 501.8.
Issued on: March 6, 1996.
Michael B. Brownlee,
Associate Administrator for Safety Assurance.
[FR Doc. 96-5801 Filed 3-7-96; 10:36 am]
BILLING CODE 4910-59-P
