Interpretation ID: aiam3484
Senior Test Engineer
Dayton T. Brown
Inc.
Church Street
Bohemia
Long Island
NY 11716;
Dear Mr. Wachsmuth: This responds to your recent letter requesting an interpretation o paragraph S4.4(b)(3) of Safety Standard No. 209, *Seat Belt Assemblies*, as it applies to a continuous-loop, Type 2 seat belt assembly. You ask whether each structural component of such a seat belt assembly should be considered 'common' hardware for both the pelvic and upper torso portions of the assembly.; Paragraph S4.4(b)(3) of Standard No. 209 specifies that the structura components in a Type 2 seat belt assembly that are common to pelvic and upper torso restraints shall withstand a force of not less than 3,000 pounds. Arguably, in a continuous-loop system with a sliding buckle latchplate, every since, as your letter points out, if one of the components should fail, the entire assembly could be rendered useless. However, the agency has stated in the past that testing for compliance with paragraph S4.4 of the standard on continuous- loop, Type 2 assemblies will be conducted by using a webbing clamp to segregate the portion of the assembly not being tested, i.e., to separate the pelvic and upper torso portions. This means that in continuous-loop assembly without the use of webbing clamps, the agency determined that such a test method is extremely difficult to perform. I am enclosing copies of two earlier letters of interpretation on this subject.; In light of this prior interpretation, the agency cannot conclude tha all components of a continuous-loop system are 'common' hardware for purposes of S4.4(b)(3). Rather, it is our opinion that only the latchplate, buckle and the inboard seat belt anchorage are common hardware for purposes of S4.4(b)(3). The belt retractor and the 'D' ring should be considered only part of the upper torso portion of the continuous-loop system.; I would point out that it is up to the vehicle manufacturer t determine and certify compliance with all applicable safety standards under the National Traffic and Motor Vehicle Safety Act. The agency does not provide prior approval of any safety design or test method. Therefore, you are free to test seat belt assemblies by any method you believe to be sufficient to establish due care that the assemblies are in compliance with Safety Standard No. 209. In our opinion, however, the test method mentioned in your letter would maintain a somewhat higher standard of performance than that currently required by the standard.; Sincerely, Frank Berndt, Chief Counsel