Bornemann Products, Inc.
402 Industrial Drive
Bremen, IN 46506
Dear Mr. Wagner:
This responds to your letter of January 10, 1995, requesting further interpretation of how the requirements of Standard No. 207, Seating Systems, would apply to an integrated seat.
Your first question is a follow-up to our December 23, 1994, letter concerning the requirements of S4.2.1 of Standard No. 207. Section S4.2.1 states:
Except for vertical movement of nonlocking suspension type occupant seats in trucks or buses, the seat shall remain in its adjusted position during the application of each force specified in S4.2.
You asked for confirmation that a "rachet-style seat recliner mechanism may not have its adjustment teeth shear during the test, ... assuming that the shearing of the recliner's teeth is a change in detent position." This is correct.
Your second question concerns "continuous engagement." You described "continuous engagement" as follows:
continuous engagement ... simply implies that the seat recliner or slides will always be in a locked position, even during adjustment. Some slides and recliners, for adjustment purposes, must be "unlocked," or released, allowing for the adjustment to be made, but then automatically relock when the desired position is achieved; this adjustment is not considered to be as continuously engaged, since the mechanism is in a released state during adjustment.
An apparatus that might be considered to be a continuous engagement device might be a screw- drive mechanism, which can be adjusted by revolution, but would always have a locking feature, even during adjustment (and never be in a released position).
You asked whether the recliner on an integrated seat must have "continuous engagement" to comply with the safety standards.
In the December 23 letter, I explained that NHTSA may choose to test a seat in any of the range of possible reclined positions. However, this does not require "continuous engagement." If a seat has specific adjustment positions, and is released or unlocked to move between those positions, NHTSA would not test the seat between adjustment positions.
I hope this information has been helpful. If you have any other questions, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992.
Philip R. Recht Chief Counsel