Interpretation ID: aiam1895
Vice President
American Mutual Insurance Alliance
20 North Wacker Drive
Chicago
IL 60606;
Dear Mr. Segraves: This is in response to your letter of March 19, 1975, requestin additional information on two aspects of the March 12, 1975, Federal Register notice (40 FR 11598) proposing to amend the Federal bumper standard.; Your first question relates to the proposed reduction in the number o required longitudinal pendulum impacts from 6 to 2, front and rear. According to a Transportation Systems Center report dated July 1974, an average car is involved in 4.7 low speed (5 mph or below) accidents in its 10-year or 100,000-mile lifetime. Of these, 1.25 are insurance reported, 33% of which are front or rear collisions, 1.25 are repaired but not insurance reported, 62% of which are front or rear collisions, and 2.20 are unrepaired, 38% of which are front or rear collisions. The conclusion reached in the report is that a vehicle is involved in 2.03 front or rear low-speed collisions in its lifetime.; The NHTSA has no specific information regarding reduction in weight an cost of vehicles due to the lowering of the number of pendulum impacts.; Responding to your second question, the NHTSA has not determined wha the cost-benefit trade-off would be in permitting damage to the bumper face bar components and associated fasteners. The decision to allow such damage until 1979 was based on a determination that some manufacturers needed that amount of lead time in order to produce vehicles capable of meeting the more stringent damage criteria. The proposed schedule for implementation of the surface damage criteria would not effect a lowering of the current level of bumper performance and would permit adequate time for the development of more durable bumper systems.; Sincerely, James C. Schultz, Chief Counsel