Interpretation ID: nht72-4.26
DATE: 03/16/72
FROM: AUTHOR UNAVAILABLE; Robert L. Carter; NHTSA
TO: Wingard Limited
TITLE: FMVSS INTERPRETATION
TEXT: This is in reply to your letter of February 10, 1972, regarding interpretation of certain parts of Federal Motor Vehicle Safety Standard No. 209, Seat Belt Assemblies.
In regard to your question on performance of retractors, the standard specifies that "an emergency-locking retractor or a non-locking retractor attached to upper torso restraint shall be subjected to 45,000 additional cycles of webbing withdrawal and retraction between 50 and 100 percent extension." This requirement applies to all emergency-locking retractors whether attached to the pelvic or upper torso restraint and only to those non-locking retractors that are attached to the upper torso restraint.
In regard to the 45,000 additional cycles, one cycle consists of extending the webbing from 50 to 100 percent extension and return to 50 percent.
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