Interpretation ID: aiam2744
602 Cordova Place
Davis
CA 95616;
Dear Mr. Mrak: This is in reply to your letter of December 12, 1977, to Secretary o Transportation, Mr. Brock Adams, concerning the seat belts in your automobile.; Federal Motor Vehicle Safety Standard No. 208, Occupant Cras Protection, requires that the distance between the lap-shoulder belt intersection and the vertical center line of a 50th percentile (164 pounds, 5 feet 8 inches) adult male occupant must be at lease six inches when the seat is in its rearmost position. The purposes of this requirement is to reduce the risk of the occupant 'submarining' out from under the belt and to reduce the possibility of the shoulder belt pulling the lap belt up onto the abdomen where it could cause serious injury in a crash.; The possibility of submarining increases as the intersection of th lap-shoulder belt is moved toward the occupant's centerline and/or as seat cushion rigidity is reduced. In other words, the closer the intersection of the lap-shoulder belt is to the centerline of the occupant, and the softer the seat, the more the danger of 'submarining' in a crash. The standard does not limit the maximum distance from the occupant's centerline to the lap- shoulder belt intersection because of varying degrees of seat rigidity and installation configurations. Thus, contrary to what you may have been told, manufacturers who provide belt systems with distances greater than six inches do so by choice and not because they are required to do so by Federal standards.; Thank you for informing us of your problem. Sincerely, Elwood T. Driver, Acting Associate Administrator fo Rulemaking;