Interpretation ID: nht72-3.31

DATE: 11/27/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Recreational Vehicle Institute, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: Your letters of September 8 and October 16, 1972, raise a question concerning the applicability of S4.3 of Standard 207 to certain folding seats in recreational vehicles. Your position is that the typical dinette seat that folds down to form a bed is "a seat having a back that is adjustable only for the comfort of its occupants" and is therefore excepted from the restraining device requirement of S4.3.

In a letter that we sent to Auto Top, Inc. on September 8, 1972, we distinguished between excepted seats and non-excepted seats on the basis of the degrees of arc through which the back could be adjusted. A back adjusting only a few degrees would be excepted under this interpretation, while a seat that folded flat to make a bed would not be excepted and would therefore have to have a restraining device. After reconsidering the background of these exceptions, we have decided to modify that interpretation. Although there is likely to be a difference between these seats in the degree of protection they give the occupant, we cannot find that this difference was reflected in the drafting of the S4.3 exceptions.

The S4.3 exceptions were created by a notice of rulemaking published April 4, 1967 (32 F.R. 5498). The exception in issue here was adopted in response to a petition by the Rover Company, who requested special treatment for a seat with a back that had a range of adjustment from 77 degrees to the horizontal down to 19 degrees to the horizontal. In granting an exception to the type of seat depicted by Rover, the agency therefore included seats with backs that folded until they were substantially horizontal. We must thus conclude that a seat whose back folds backward with respect to the seat cushion to form a bed is not required under S4.3 to have a device to restrain the backward folding of the seat back.

However, the exemption granted in response to the Rover petition does not cover the case you have described. A seat having a back that folds for the occupant's comfort but that also folds in another manner is required to have a restraining device for the second folding mode. The usual example of such a seat is a front seat in a two-door sedan that folds forward for entry to the rear and has a back that adjusts through a rearward arc for the occupant's comfort. Such a seat must have a restraining device to prevent forward movement because the adjustment of the back is not "only" for the occupant's comfort. A dinette seat that has an additional folding or hinging mode must therefore have a restraining device to guard against the effects of the seat's folding in this mode during a crash. For example, a seat whose base is hinged to move the bottom cushion into the space between the dinette seats must be restrained by a device conforming to S4.3.

With specific reference to the type of seat shown in the attachments to your letters, the downward motion of the seat back would be exempt under S4.3, but the motion of the bottom cushion is such that it would have to have a restraining device conforming to S4.3.

As you describe the seat, a restraining device is provided. However, without subjecting it to a compliance test under S4.3.2 we are unable to say whether it conforms to S4.3.