bing and retractor shall be subjected to a tensile force of 2,500±25 pounds or 1,135 10 kilograms with the webbing fully extended from the retractor, or to a tensile force of 1,500±15 pounds or 680±5 kilograms with the webbing fully extended from the retractor if the design of the assembly permits only upper torso restraint forces on the retractor.

(6) If a seat belt assembly has a buckle in which the tongue is capable of inverted insertion, one of the three assemblies shall be tested with the tongue inverted.

(c) Type 3 seat belt assembly. Three seat belt assemblies including webbing, straps, buckles, adjustment and attachment hardware and retractors shall be tested in the following manner:

(1) The testing machine shall conform to the requirements specified in § 9.7(b). A torso having the dimensions shown in Figure 6 shall be attached to one head of the testing machine through a universal joint which is guided in essentially a frictionless manner to minimize lateral forces on the testing machine. An anchorage and simulated seat back shall be attached to the other head as shown in Figure 7.

(2) Attachement hardware for an assembly having single webbing connection shall be fastened at the anchor hole shown in Figure 7 which is centered along the length of the anchorage bar. Attachment hardware for an assembly having two webbing connectors shall be fastened at anchor holes 16 inches or 40 centimeters apart on the anchorage bar, equidistant from the center. Attachment hardware for an assembly whose design precludes such attachment shall be fastened in accordance with the installation instructions. The back of the torso shall be positioned in a plane parallel to and at a distance of 4 inches or 10 centimeters from the plane of the simulated seat back. The seat belt assembly shall be installed on the torso in accordance with installation instructions and the webbing to the attachment hardware shall be adjusted with effectively no slack. The heads of the testing machine shall be separated at a rate of between 2 and 4 inches per minute or 5 and 10 centimeters per minute until a force of 2,000 pounds or 900 kilograms is applied. The extension of the seat belt assembly shall be determined from

measurement of head separation in the testing machine before and after the force is applied. The force shall be reduced to 45±5 pounds or 20±2 kilograms and the release force of the buckle or buckles measured as prescribed in § 9.8 (d). A seat back retainer not connected to pelvic or upper torso restraint shall be subjected separately to a force of 2,000 pounds or 900 kilograms.

(3) After the buckle is released, the webbing shall be examined for cutting by the hardware. If the yarns are partially or completely severed in a line for a distance of 10 percent or more of the webbing width, the cut webbing shall be tested for breaking strength as specified in § 9.7(b) locating the cut in the free length between grips. If there is insufficient webbing on either side of the cut to make such a test for breaking strength, another seat belt assembly shall be used with the webbing repositioned in the hardware. A tensile force shall be applied to the components as follows: Webbing in pelvic or upper torso restraint-700±7 pounds or 320±3 kilograms; webbing in seat back retainer or webbing connecting pelvic and upper torso restraint to attachment hardware 1,500±15 pounds or 680±7 kilograms. After the force is removed, the breaking strength of the cut webbing shall be determined as prescribed above.

(4) If a seat belt assembly has a buckle in which the tongue is capable of inverted insertion, one of the three assemblies shall be tested with the tongue inverted.

§ 9.10 Provision for changes in the standards.

Section 4 of the act provides for the possibility of changes in the standards first established pursuant to section 1 of this act. Any person, firm or organization wishing to propose a change in these standards shall submit the detailed proposal to the Director, National Bureau of Standards, U.S. Department of Commerce, Washington, D.C. 20234.

§ 9.11 Effective date.

The standards prescribed herein shall become mandatory after February 28, 1967, and until this date shall be optional alternatives to the standards published in the FEDERAL REGISTER on July 1, 1965.