Interpretation ID: aiam3948
Ashimori Industry Co.
Ltd.
12
4-chome Yokobori
Higashi-ku
Osaka
Japan;
Dear Mr. Mizuguchi: Your letter of February 28, 1985, was forwarded to my office for reply You asked whether the webbing attached to a buckle you intend to use must meet the webbing width requirement of S4.2 of Standard No. 209, *Seat Belt Assemblies*. The webbing is enclosed in a plastic sheath. As explained below, the webbing must meet the width requirement of the standard.; S4.2 of Standard No. 209 provides that the 'width of the webbing in seat belt assembly shall be not less than 1.8 inches, except for portions that do not touch a 95th percentile adult male with the seat in any adjustment position and the seat back in the manufacturer's nominal design riding position when measured under the conditions prescribed in S5.1(a).' The purpose of S4.2 is to ensure that belt webbing which comes into contact with an occupant has a minimum width that spreads the load imposed by the belt in a crash. By requiring webbing to spread rather than concentrate the load, the belt width requirement helps minimize the possibility of webbing-caused injury.; In the case of your design, the webbing is enclosed in tightly-fitting plastic sheath. You state that the webbing/sheath combination can come into contact with an occupant. The sheath enclosed with your sample is made from an easily deformable plastic. Thus, when the crash loads are imposed by the belt, the sheath will deform and the crucial factor in concentrating the load on an occupant is the width of the belt. Since the webbing/sheath combination can contact and impose crash loads on an occupant, the agency concludes that the webbing must meet the minimum width requirement of S4.2.; If the webbing were encased in a reinforced sheath that did no appreciably deform under loading, the agency would consider both the width of the webbing and its encasing sheath in determining whether the requirement of S4.2 was met.; I have enclosed the sample of your product sent with your letter. I you have any further questions, please let me know.; Sincerely, Jeffrey R. Miller, Chief Counsel