Interpretation ID: GF009138

Mr. Kenneth M. Bush
Associate Director, Government. Relations
American Suzuki Motor Corporation
3251 East Imperial Highway
PO Box 1100
Brea, CA 92822-1100

Dear Mr. Bush:

This responds to your letter concerning Federal Motor Vehicle Safety Standard (FMVSS) No. 201, "Occupant protection in interior impact". Specifically, you ask whether side curtain air bag tethers are considered a part of the "stowed system" that is subject to reduced impact speed upper interior component performance requirements. As discussed below, the answer is yes.

By way of background, S6.2 of FMVSS No. 201 sets minimum performance requirements for upper interior components by establishing target areas that must be properly padded or otherwise have energy absorbing properties to minimize head injury in the event of a crash. Compliance with the upper interior component requirements is determined, in part, by measuring the forces experienced by the Free Motion Headform test device (FMH) when it is propelled into certain targets on the vehicle interior at the speed of 24km/h (15 mph), or in some cases, at the reduced impact speed of 19 km/h (12 mph).

Air bag systems are frequently stowed (in their un-deployed state) in the same interior areas where certain test targets are located. Targets located on or near air bag systems are subject to reduced impact speed test requirements because the agency is concerned that requiring areas over the stowed portion of an air bag (or its attachment and other hardware) to meet more stringent 15 mph impact requirement could hinder their development and use. Thus, in order to accommodate the current systems and the development of new or additional air bag systems, we determined that use of a 12 mph impact speed, in conjunction with a full-vehicle dynamic side impact pole test, would best help realize the safety benefits of air bags. In relevant part, S6.2(b)(2) of FMVSS No. 201 reads as follows:

"Targets that are over any point inside the area measured along the contour of the vehicle interior within 50 mm (2.0 inch) of the periphery of the stowed system projected perpendicularly onto the vehicle interior surface, including mounting and inflation components but exclusive of any cover or covers, when the dynamically deployed upper interior head protection system is not deployed, shall be impacted by the free motion headform specified in S8.9 at any speed up to and including 19 km/h (12 mph) with the system undeployed" [emphasis added]

You ask if stowed side curtain tethers are considered part of the "stowed system" under S6.2(b)(2).As used in S6.2(b)(2), "stowed system" refers to a stowed dynamically deployed upper interior head protection system. The language ofS6.2(b)(2) specifies that in determining the area subject to reduced impact speed test requirements, consideration is taken of the stowed system, including mounting and inflation components but exclusive of any cover or covers. Side curtain air bag tethers are a part of the stowed dynamically deployed upper interior head protection system, and they are not "covers". Therefore, they are considered in determining whether the target issubject to reduced impact speed test requirements.

If you have any further questions, please feel free to contact George Feygin of my staff at (202) 366-2992.

Sincerely,

Stephen P. Wood
Acting Chief Counsel

ref:201
d.4/17/06