Interpretation ID: aiam0820
Robert Bosch GmbH
Department K/BEW3
7 Stuttgart 30
Postfach 400
Germany;
Dear Mr. Hammerstein: Your Broadview, Illinois, Subsidiary recently forwarded to us a copy o your December 17, 1971, letter concerning aiming adjustment tests as specified in SAE Standard J580a. A search of our files does not reveal that your letter was previously received by this Office.; Specifically, your concern is the interpretation of a requirement whic is specified in SAE J580a as follows:; >>>'2. The mechanism, including the aiming adjustment, must be s designed as to prevent the unit from receding into the lamp body or housing when an inward pressure of 50 lb(sic) is exerted on the outer surface of the lens.'<<<; Our interpretation of the above requirement is that no visible recedin of the sealed beam unit is permitted when the inward pressure is applied on the outer lens surface. Testing for compliance to the requirements of FMVSS No. 108, which references SAE J580a, is conducted on the basis of this interpretation.; In the upcoming Notice of Proposed Rule Making (NPRM) on FMVSS No. 10 (Docket 69-19), we are considering the feasibility of specifying more objective type requirements on this aspect of aiming adjustment tests for headlamps. You will no doubt be interested in commenting on the proposed requirements after issuance of the NPRM.; Sincerely, E. T. Driver, Director, Office of Operating Systems, Moto Vehicle Programs;