Seat Belt Webbing Technical Specification
|Publication Date:||1 June 2017|
Note: Nothing in the specification supercedes applicable laws and regulations unless specific exemption has been obtained.
Note: In the event of conflict between the English and domestic language, the English language shall take precedence.
This specification establishes the seat belt webbing requirements for 3 - point seat belt assemblies intended to provide design verification and compliance to the Federal Motor Vehicle Safety Standard (FMVSS) 209 and other global regulatory requirements for future General Motors (GM) vehicles. It defines common key physical and functional requirements enabling interchangeability between supplier systems for GM vehicles worldwide. This set of specifications is intended to provide uniform direction to the various engineers regarding the design requirements, testing, and validation of each seat belt system being developed for GM vehicles. In part, when validated to these requirements, the seat belt system will provide a reasonable and appropriate level of performance in real world crashes.
This specification does not apply to seat belt webbing used as buckle straps, guide loop straps, or in 2 - point seat belt assemblies.
Material Description. This specification describes a narrow woven fabric (polyester is used unless otherwise directed by GM Engineering) used in certain seat belt applications. The webbing described in this specification is only intended for use within retractor-side assemblies of 3 - point seat belts. The material is constructed with a double needle loom using monofilament and multifilament weft yarns. The following data shall be made available: The Yarn Description (Source, Fiber Content, Denier, Twist Direction, turns per 25 mm, Luster, Cross-Section). The material has knit selvages that are rounded and completely hide the weft reverse points of the monofilament.
Symbols. Not applicable.
Applicability. Webbing described in this specification is classified as being either:
Type A: Standard thickness webbing for use in most applications.
Type B: Slightly thinner webbing for use in selected applications where additional webbing will be needed to stow into a retractor that otherwise couldn't stow that length of webbing.
Type C: Low Elongation webbing for use in selected applications where a lower elongation rate is required. Low Elongation webbing is also thinner than Type A webbing.
Type D: High Elongation webbing for use in selected applications where a higher elongation rate is required. High Elongation webbing is also thicker than Type A webbing. Except where explicitly indicated, there are no differences, other than thickness changes, in the requirements for Type A, Type B, Type C and Type D webbing.
Remarks. Seat belt webbing is a textile product that is an integral component of a seat belt assembly. Vehicle seat belts are intended to provide injury protection benefit to occupants of the vehicle in the event of a crash. Their primary function is to restrain an occupant (or child seat), and to reduce the risk or severity of injury by managing the occupant's kinetic energy.
Seat belt webbing must function in harmony with the rest of the seat belt subsystem, be as comfortable and unobtrusive as practicable, and be in visual harmony with the interior theme of the vehicle.
Webbing must also comprehend the differences in governmental and market requirements of the different countries in which it is sold.