Interpretation ID: nht72-4.6

DATE: 03/29/72

FROM: AUTHOR UNAVAILABLE; Douglas W. Toms; NHTSA

TO: Automobile Manufacturers Association, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of March 3, 1972, in which you asked to be referred to the information on which we based our statement in the notice of February 24, 1972, that systems meeting the injury criteria of Standard 208 are available using current seat belt technology.

Research data on the capabilities of seat belts are found in several places in the public docket, notably in the progress reports from our Safety Systems Laboratory and from Cornell Aeronautical Laboratory (69-7 General Reference Nos. 74, 75, 83, 96, 102, 117, 120 and 135). There are records of vehicle tests in which current lap and shoulder belt systems have met the injury criteria (see, e.g. N<13>-69-7-20; N<13>-69-7-37). Also, the record contains information on energy absorbing webbing and anchorages, both of which are improvements within the current state of the art (see, for example, the 6th progress report from Cornell, runs no. 625-630, 69-7 General Reference No. 135; the data from Toyota in N<13>-69-7-23; and the Takata Koyjo data in N<16>-16-69-7-1).

Although the behavior of the head seems to be a greater problem for belt systems than the behavior of the chest, due in part to the effects of rebound, we have proposed changes in the head injury criterion that should ease the problem considerably.