Interpretation ID: nht73-2.2

DATE: 08/30/73

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Electrical Testing Laboratories, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of June 18, 1973, concerning the conformity of certain designs of type III seat belt assemblies with Standard No. 209.

The first feature which you describe is a restraint consisting of a waist band with a single shoulder strap. The shoulder strap is attached to the buckle in front and is looped around the waist band in back. Unless this restraint has more elements then you describe, we haver serious questions about its conformity with the requirements for type III seat belts under Standard 209. Section S4.1(c) provides that the assembly must restrain the upper torso without shifting the pelvic restraint into the abdominal region and that the upper torso restraint shall be designed to minimize its vertical forces on the shoulders and spine. It appears doubtful that the described assembly meets either of these requirements.

The second feature you described is a strap through the harness assembly that passes around the seat back and is anchored to the floor by means of the vehicle's seat belt assembly anchorage. Your question appears to be whether such a restraint is a seat back retainer as required by Section S4.1(h). The attachment you describe would not be a seat back retainer under Section S4.1(h).

The third feature described, a closed loop strap without floor attachment would also violate the requirements of S4.1(h), unless it is designed and labelled for use only in specific models having adequate seat back restraints, as specified in that paragraph.

The fourth feature is the ability of a harness to move freely up and down on the restraint strap. This feature is the ability of harness to move freely up and down on the restraint strap. This feature is allowable under Standard 209.

Yours truly,

ELECTRICAL TESTING LABORATORISE, INC.

June 18, 1973

Richard Dyson -- Office of the Chief Counsel, National Highway Traffic Safety Administration

Subject: Type 3 Seat Belt Assemblies.

Dear Mr. Dyson:

We have recently been asked to perform tests on type III seat belt assemblies, the design of which has caused us some doubt as to their meeting some of the requirements of FMVSS 209. What we would like to know is whether or not the following design features are acceptable under the requirements for type III seat belt assemblies as outlined in FMVSS 209.

1. Upper torso restraint: Restraint consists of single strap starting at the midpoint of the pelvic band (strap around the waist). The anchor point is the buckle tongue hardware. The strap then passes over on shoulder of the child and is terminated in a loop through which the pelvic belt passes freely.

2. Seat Back Retainer: Strap passes through harness assembly around seat in a closed loop and is anchored to the vehicle by a narrow anchor plate using the same bolt as used to secure the seat belt assembly. This installation is performed by the purchaser.

3. Strap: The harness assembly is secured to the seat back by a closed loop strap. No seat back restraint provided.

4. Harness assembly: The harness assembly is secured by either the seat back retainer or strap and is free to move up or down on this section of webbing.

The specimens we have in for test are combinations of the above features and as such we would appreciate knowing what features are acceptable and which are not.

Should you require any additional information on this subject, in relation to the descriptions, please contact either Mr. H. D. Pomponio or myself.

Very truly yours,

C. F. Robb -- Manager, Automotive/Mechanical Division