Blue Bird Body Company (Blue Bird), 402 N. Camellia Blvd., P.O. Box 937, Fort Valley, Georgia 31030, has determined that 25,839 model TC/2000 Conventional and MiniBird school buses do not meet the 60 percent tensile strength requirements of 49 CFR 571.221, Federal Motor Vehicle Safety Standard (FMVSS) No. 221, “School bus Body Joint Strength,” and has filed an appropriate report pursuant to 49 CFR part 573, “Defect and Noncompliance Reports.” Blue Bird has also applied to be exempted from the notification and remedy requirements of 49 U.S.C. Chapter 301—“Motor Vehicle Safety” on the basis that the noncompliance is inconsequential to motor vehicle safety.
This notice of receipt of an application is published under 49 U.S.C. 30118 and 30120 and does not represent any agency decision or other exercise of judgement concerning the merits of the application.
FMVSS No. 221, S5 requires that when tested in accordance with the test procedures of S6., each body panel joint shall be capable of holding the body panel to the member to which it is joined when subjected to a force of 60 percent of the tensile strength of the weakest joined body panel determined pursuant to S6.2.
Blue Bird has notified the National Highway Traffic Safety Administration that the subject school buses were manufactured at their Mount Pleasant, Iowa, plant between November 1, 1993 through December 6, 1999. The noncompliance involves a failure to meet the 60 percent joint strength requirements on certain 8 inch segments of the exterior roof joints. Agency compliance tests, performed by General Testing Laboratories (GTL), determined that the tensile strength of the roof joint tested was 54.9 percent of the required load. Blue Bird stated that a variance in rivet spacing in the vicinity of the roof stringers occurred as some assembly workers at this plant without authorization, departed from manufacturing procedures of using the pre-punched holes in the roof bows as drill guides to control fastener spacing and, as a result, there are fewer than the six (6) rivets required by Blue Bird in certain eight (8) inch segments of the roof joints in the affected buses.
Blue Bird supported its application for inconsequential noncompliance with the following:
I. Overall Joint and Body Strength
The stated purpose of the School Bus Body Joint Strength Standard No. 221 is “* * * to reduce deaths and injuries resulting from the structural collapse of school bus bodies during crashes.” In Docket No. 7334: Notice 1, Federal Register, Vol. 39, No. 15—Tuesday, January 22, 1974, the agency observed that FMVSS 221 “derives from section 5.6 of the Vehicle Equipment Safety Commission's Regulation VESC-6 * * * ” Docket No. 73-34 went on to state that,
“In order to bring the basic VESC—6 requirement into a form that satisfied the legal and operational requirements of the motor vehicle safety standards, the agency has included a test procedure to make possible an objective determination of a joint's strength.”
The selected test procedure established the use of a twelve (12) inch wide test specimen necked down to eight (8) inches at the center, such that the strength of the joint is evaluated by tensile testing of a randomly selected eight (8) inch long segment of the joint being evaluated. Later in the docket NHTSA outlined its regulatory objective:
“The agency therefore anticipates that the procedure will permit the overall strength of a bus's joints to be determined without resorting to an unduly burdensome amount of testing.“
Blue Bird concludes from the above discussion that the strength of the overall joint and consequently the strength of the overall bus body is the safety objective of standard 221 and that the measured performance of an eight (8)-inch long joint segment is merely a procedure chosen to evaluate the overall joint in a practical manner.
During a December 2, 1999 Blue Bird personnel visit to the GTL facility in Leedstown, VA, the 1998 Blue Bird test bus was inspected and photographed. Paper tape was secured at each roof joint and the location of each rivet in each joint was marked on the tape. Blue Bird thereafter analyzed each tape and the length of each joint and the total number of fasteners in each joint were determined. On average, the seven (7) roof joints on the test bus had 6.76 rivets per eight (8) inches of length. Based on the reported test results of 6220 pounds for the roof joint tested that had five (5) rivets, the strength per rivet is 1244 pounds per rivet, and for the average joint with 6.76 rivets, this equates to a strength of 8409 pounds per eight (8) inch length which far exceeds the required strength of 6788 pounds. This 8409 pound strength equates to a 73.3 percent efficiency as compared to the 60 percent required by Standard 221.
Similarly, the worst case roof joint on the test bus had 6.62 rivets per eight (8) inches of length, which equates in a similar manner to 8239 pounds per eight (8) inch length for an efficiency of 72.8 percent. Here again, this comfortably exceeds the 60 percent requirement of Standard 221.
This analysis shows that the overall strengths of the roof joints on the subject test bus not only meet—but comfortably exceed the strength performance requirements of FMVSS 221. Consequently, Blue Bird believes that the noncompliance of several small selected segments of these roof joints is not representative of actual, overall bus body strength performance and is inconsequential as it relates to motor vehicle safety.
II. Occupants Not Exposed to Roof Joints
In reviewing the regulatory history of FMVSS 221, Blue Bird notes that this rulemaking had a complementary purpose to minimize the likelihood of sharp edges of sheet metal being Start Printed Page 13413produced by joint separations or gross body deformation in crashes. For interior panel joints it could be argued that the eight (8) inch joint segment length was also chosen to help accomplish this purpose. However, in a crash, vehicle occupants are not exposed to exterior joints like the roof joint in question, and the interior panel sheet metal concern would not be applicable. Also of importance is the fact that the few small segments of exterior roof joints believed to be in noncompliance are completely separated from the occupant compartment by headlining panels with joints in full compliance (71.3%) with FMVSS 221 requirements.
III. Interior Headlining Joint and Overall Bus Body Joint Strength
For school bus bodies, Blue Bird reiterates that the overall strength of the joints is of critical importance with regard to the purpose of Standard 221. Blue Bird notes and emphasizes that the GTL test results showed that the headlining joint performance was 71.3 percent vs. the 60 percent requirement. Extending the analysis in I above, if the strength of the entire body joint consisting of both the interior headlining joint and the exterior roof joint were to be analyzed together, the overall performance of the joint would be 62.4 percent, which exceeds the 60 percent requirement of FMVSS 221 and satisfies the stated purpose and safety objectives of the standard.
IV. The Remedy in this Case Could Result in Degradation and Leakage of Bus Body Panels
There is no safety need to require notification and remedy of the subject school buses to add additional fasteners. Blue Bird believes that in reality, a recall of the subject buses would be counterproductive to safety in that the resulting inconvenience to the owners/operators of the buses could disrupt the service they provide, resulting in the use of much less safe means of transportation.
Equally important, the only feasible remedy on completed buses is the addition of blind repair (pop type) rivets in the areas where there are less than six (6) rivets in each eight (8) inch segment. Blind rivets are susceptible to water leaks and the installation of these rivets could result in mechanical damage to the roof joint sealer and possible damage to the exterior body paint. Water leaks and/or possible corrosion could occur as a result of the mechanical damage done during drilling and rivet installation.
V. The Current Status of FMVSS 221 Indicates That Curved Joints Are Not a Safety Concern
The current version of FMVSS 221, which permitted optional early compliance as of November 5, 1998, provides an instructive insight into the agency's position with respect to curved joint testing. The November 1998 final rule (see Reference 3), in § S5.2.2, appears to exclude all curved and complex joints from the 60 percent strength. requirements of § S5.1.2.
While in a technical sense this revised Standard 221 does not apply to the September 1998 test bus, Blue Bird notes that (1) the GTL test occurred one year after the revised FMVSS 221 became optionally effective, and (2) the roofjoint tested in November 1999 by GTL was in fact a curved panel joint.
To Blue Bird, the thinking and intent of the agency to exclude all curved joints from the joint tensile strength requirements of revised Standard 221 was unambiguous, as borne out by the following statements from the rule's preamble:
“This rule excludes from the joint tensile strength requirement joints from which a test sample cannot be obtained because of the size of the joint or the curvature of the panels comprising the joint.”
“NHTSA recognizes that the curved shape of such joints poses difficulty in obtaining accurate test results. The application of force on a curved surface would cause the surface to flatten, thus misrepresenting the actual force loading on the panel.” “Since the agency is not aware of any data indicating that injuries have been caused disproportionately by curved joint separation, NHTSA believes that the potential costs and technical difficulty of testing curved joints more than outweigh any potential safety benefits.”
“Accordingly, NHTSA has decided that test specimens from joints with discrete fasteners will be taken from 305 mm (12 inch) segments (203 mm (8 inches) at the neck) of only flat body panels.”
“While curved, small and complex joints are excluded from the tensile test requirement because they cannot be accommodated on the test apparatus, they are nevertheless subject to the requirement in S5. 1.1 that no body panel, when joined to another body panel, shall have an unattached segment at the joint longer than 203 mm. (8 inches). Presumably rivets or other fasteners will be used. This requirement helps ensure that the joints will maintain their integrity in a crash.”
Based on the belief that the final rule excluded all curved joints, and for other reasons, Blue Bird first initiated an urgent meeting with NHTSA in early December 1998, then petitioned the agency in a December 16, 1998 letter to reconsider the final rule and thereafter attended a second meeting with NHTSA and other major school bus manufacturers in January 1999. In each instance, Blue Bird urged the agency to properly address the issue of curved joints, including properly defining them and/or showing side and end views of Figure I with tolerances. The meetings and petitions also pointed out other problems with the final rule. In Blue Bird's December 16, 1998 Petition for Reconsideration, the Company went so far as to provide the recommended regulatory text needed to properly amend the final rule. Even so, this final rule has been allowed to stand without corrective amendment or extension for approximately fifteen (15) months despite the objections, petitions and continued urging from the industry.
Until the standard properly defines what does or does not constitute a “curved joint,” the actual requirements that roof and ceiling joints must meet will continue to be unclear. By not taking action to correct or clarify the final rule, Blue Bird believes that the agency is saying that one rivet per eight inch segment is sufficiently safe for these joints, as well as other curved, complex and small joints, and is allowing school buses to be manufactured in this manner. Since no action has been forthcoming, we must conclude that curved joints, including roof and ceiling joints, do not constitute enough of a safety issue to warrant making corrections and/or clarifications to the final rule of Reference 3.
VI. There Have Been No Roof Joint Failures in the Field
Blue Bird has never had a field complaint regarding the strength of roof joints and is not aware of any accidents or crash tests which resulted in roof joint separations within the scope of the Standard. The NHTSA test bus from which the subject roof joint was obtained had other joints tested and all were found to be in full compliance with all FMVSS 221 requirements. Further, the same bus had previously been tested and found to be compliant with the agency's other school bus body construction standard, FMVSS 220—School Bus Roll Over Protection.
VII. Blue Bird's Corrective Actions Were Immediate on Learning of the Test Failure
Blue Bird responded quickly to the reported test failure. An internal review was initiated immediately and field inspection and analysis of vehicles in service was conducted to determine the potential scope of the reported test failure. A visit to the General Testing Laboratories facility in Leedstown, Virginia, to gather testing details and Start Printed Page 13414related vehicle information was immediately requested and quickly accomplished. All production facilities were alerted of the situation so assembly procedures would be checked and any required corrective action taken.
The Company's internal review, field inspection and analysis showed that the departure from manufacturing procedures that resulted in the reported test failure was limited to Blue Bird's Midwest Plant in Mount Pleasant, Iowa, during the period beginning November 1, 1993 and ending when corrective action was implemented in early December 1999. All other plants reported ongoing conformance with assembly instructions, such that all such bus roof and other joints were manufactured in compliance with FMVSS 221 requirements.
Blue Bird Midwest initiated corrective procedures in its assembly processes immediately upon notification of the test failure. All units placed in assembly on or after December 6, 1999, have roof joint rivets spaced in conformance with assembly procedures to assure compliance with FMVSS 221 joint strength performance requirements. Further, once a determination of noncompliance was made, a stop delivery order was issued to insure that all units still in Blue Bird Midwest's possession and control were corrected prior to delivery to distributors.
The above facts and discussion have described a noncompliance that has been determined to exist on certain Blue Bird school buses. The Company does not in any way wish to discredit or minimize the performance requirements or test procedures of FMVSS 221 because of this noncompliance. Blue Bird takes full responsibility for the noncompliance that occurred and has explained how it occurred, why the noncompliance is not a safety problem and that corrective action to prevent future occurrences has been taken.
Blue Bird firmly believes that the noncompliance is inconsequential and in no way compromises the safety of the subject school buses and that the disruption of our customers and likely degradation of these buses by the indicated remedy is not in the public interest. For the reasons provided herein, Blue Bird respectfully requests that its petition for exemption be granted.
Interested persons are invited to submit written data, views, and arguments on the application of described above. Comments should refer to the docket number and be submitted to: U.S. Department of Transportation Docket Management, Room PL-401, 400 Seventh Street, SW, Washington, DC 20590. It is requested, but not required, that two copies be submitted.
All comments received before the close of business on the closing date indicated below will be considered. The application and supporting materials, and all comments received after the closing date, will also be filed and will be considered to the extent possible. When the application is granted or denied, notice will be published in the Federal Register pursuant to the authority indicated below.Start Signature
Issued on: March 8, 2000.
Stephen R. Kratzke,
Acting Associate Administrator for Safety Performance Standards.
[FR Doc. 00-6062 Filed 3-10-00; 8:45 am]
BILLING CODE 4910-59-P