Interpretation ID: nht91-4.24

DATE: June 19, 1991

FROM: Gerald Farr -- P. Eng., Senior Compliance Engineer, Compliance Engineering and Vehicle Testing, Road Safety and Motor Vehicle Regulation Directorate, Transport Canada

TO: Paul Jackson Rice -- Chief Counsel, NHTSA

TITLE: Re: FMVSS 210 - S4.3.1.1

ATTACHMT: Attached to letter dated 7-16-91 from Paul Jackson Rice (signature by Kenneth Weinstein) to Gerald Farr (A38; Std. 210)

TEXT:

I am writing at this time to determine whether or not there have been any "official" interpretations of the method used to calculate the angle specified in FMVSS 210, section 4.3.1.1. This section requires that a LINE FROM the seating reference point (or adjusted seating reference point) TO the nearest contact point of the belt with the hardware attaching it to the anchorage, must extend FORWARD from the anchorage at an angle with the horizontal of not less than 20 and not more than 75 degrees.

There are two particular areas of interest.

1. When the angle of the line which joins the two points (SRP and belt anchorage) is calculated with respect to the horizontal, is the calculation made using a three dimensional protocol or a two dimensional protocol. (The two dimensional protocol would not take into account the transverse ("y") coordinate of the two points.)

2. Have any interpretations been made concerning what constitutes "the nearest contact point of the belt with the hardware connecting it to the anchorage"?

I would appreciate receiving any information you can provide concerning this matter. I can be reached at (613)998-1999 if you wish to discuss this further.