Interpretation ID: nht91-1.48

DATE: February 20, 1991

FROM: Gary P. Toth -- Attorney, Legal Staff, General Motors Corporation,

TO: Paul Jackson Rice -- Office of the Chief Counsel, NHTSA

COPYEE: Robert A. Rogers; Barry A. Felrice; Robert Hellmuth; Steven R. Kratzke

TITLE: Re FMVSS 209 Compliance of GM Dual-Spring Retractor Designs

ATTACHMT: Attached to letter dated 4-9-91 from Paul Jackson Rice to Gary P. Toth (A37; Std. 209)

TEXT:

On September 11, 1990, representatives of General Motors Corporation (GM) met with NHTSA personnel to review several seat belt retractor designs planned for future GM products. These retractor designs included comfort features involving dual-spring rates and intentional set slack capability. By letter dated November 2, 1990 (USG 2829), we sent your office copies of the presentation materials, with a request for confidential treatment.

The purpose of this letter is to seek the agency's concurrence that the two dual-spring retractor designs we reviewed with the agency meet the minimum retraction force requirements of Federal Motor Vehicle Safety Standard (FMVSS) 209, Seat Belt Assemblies. In connection with this request for interpretation, we also seek the agency's reevaluation of a February, 1984 interpretation, which implies that use of dual-spring retractors planned by GM might be precluded by FMVSS 209. But for that interpretation, GM would have no difficulty in concluding that these designs meet the minimum retraction force requirements of S 4.3(j)(5) and (6) of FMVSS 209, when tested in accordance with S 5.2(j).

Attachments 1 and 2 of this letter contain proprietary information describing in more detail the operation of the systems we reviewed with the agency on September 11. This information is not customarily made public by GM, and contains trade secrets and commercial information within the meaning of Section 1905 of Title 18 of the United States Code. Therefore, it is our position that these attachments are entitled to confidential treatment pursuant to Section 552(b)(4) of Title 5 of the United States Code (Exemption 4 of the Freedom of Information Act) and Section 112(e) of the National Traffic and Motor Vehicle Safety Act of 1966, as amended and implemented in Part 512 of Title 49 of the Code of Federal Regulations (CFR).

Accordingly, pursuant to 49 CFR S 512.4, GM requests that Attachments 1 and 2, which have been stamped "G.M. Confidential", be withheld from public disclosure as confidential business information for an indefinite period (except for any information which will ultimately be publicly disclosed by the availability of these designs in production vehicles). Any disclosure of this information before that time is likely to result in substantial competitive harm to GM for the same reasons set forth in USG 2829 and in the certification provided with that letter.

INTRODUCTION

GM has been a strong advocate of safety belt usage and is continuing to evaluate alternative means for improving the comfort and convenience of safety belt systems. During the September 11 meeting, we reviewed two dual-spring retractor systems, both of which are intended to reduce shoulder belt pressure on all sized occupants, which we know to be a significant factor in belt comfort.

The operation of both of these retractor designs is such that when the safety belt is being worn by an occupant, a lower retractor spring rate is, or can be, engaged to minimize the shoulder belt pressure on the occupant. When the belt is removed, a higher force spring rate is engaged to effectively stow the belt webbing. Detailed descriptions of the operation of the two designs are provided in confidential Attachments 1 and 2.

FEBRUARY, 1984 NHTSA INTERPRETATION

By letter dated February 29, 1984, NHTSA issued an interpretation to the United States Testing Company, Inc., of Hoboken, New Jersey. That company sought the agency's evaluation of a retractor design utilizing a tension reducer device (comfort type mechanism), described as a "Type 2 Vehicle Sensitive Emergency Locking Retractor". The tension reducer device was activated by the vehicle door. With the door open, the mechanism operated in a high tension mode. With the door closed, the mechanism operated in a low tension mode.

The company suggested that both tension modes should be tested for retraction force effort as specified in FMVSS 209. The company also stated its opinion that: (1) the high tension mode should only be tested for minimum retraction force; and (2) the low tension mode be tested for maximum retraction force.

The agency agreed with the company's suggestion that both tension modes should be tested for retraction force effort, but disagreed with the suggestion that only the high tension mode should be tested for minimum retraction force, and that only the low tension mode should be tested for maximum retraction force. In this regard, the agency stated:

... (B)ecause Standard No. 209 does not distinguish between tension modes, we interpret the standard to require that all of its requirements must be met in both tension modes. For example, under section S4.3(j)(6), both tension modes must exert a retractive force within the 0.2 to 1.5 pound range.

The agency's interpretation, however, did not consider, or attempt to reconcile its conclusion with, S5.2(j) of FMVSS 209, which identifies the test procedure for evaluating the retractive forces specified in S4.3(j)(5) and (6). Stated differently, the substantive requirements in FMVSS 209 S4.3(j) (5) and (6) are tied directly to the test procedure in S5.2(j), and there is no analysis of how the United States Testing Company device would perform when tested in accordance with S5.2(j). The 1984 interpretation simply states that both tension modes must exert a retractive force within the specified range without reference to the procedure specified for assessing compliance to these requirements.

Factually, the United States Testing Company device is clearly distinguishable from either of the GM retractor designs. It was apparently designed to activate the lower rate spring simply depending upon whether the vehicle door was open or closed. This is not the case with either of the GM systems reviewed with the agency. The first retractor system requires intentional occupant action -- extracting three to five inches of webbing -- to activate the lover rate spring. The lower rate spring in the second system is activated only when lap belt webbing has been extracted a certain length from its stowed position.

The two GM retractor designs can be tested in accordance with the procedure in S5.2(j) without modifying the hardware or the test procedure. When tested in accordance with S5.2(j), both designs meet the minimum retractor force requirements in S4.3(j)(5) and (6). If it were necessary, however, to modify the retractor hardware or test procedure in some way so that the lower rate springs (which would not otherwise be operational) were tested separately, as is suggested by the agency's February, 1984 interpretation, it is unlikely that these springs could meet the minimum retraction force requirements in S4.3(j)(5) and (6). However, such an interpretation would impose a new substantive requirement upon dual-spring retractors divorced from the test procedure in S5.2(j).

CLOSING

In closing, GM requests that NHTSA provide us a new interpretation indicating that the dual-spring retractor designs which we reviewed with the agency on September 11, and which are further described in Attachments 1 and 2, would comply with the minimum retractor force requirements of S4.3(j)(5) and (6) if tested in accordance with S5.2(j) of FMVSS 209 without separately testing the lower rate springs. In addition, to minimize future concerns relative to the meaning or effect of the February, 1984 interpretation, we ask that NHTSA reevaluate that interpretation, and consider limiting its effect to the facts presented in the United States Testing Company letter.

We trust that the information contained in this letter and presented on September 11 will provide a sufficient basis for the agency to concur with GM's determination regarding the compliance of these dual-spring retractor designs with FMVSS 209. However, please contact me if I can be of any further assistance to you in this matter.