Interpretation ID: aiam1146

Mr. Louis C. Lundstrom,Executive Director,Environmental Activities Staff,General Motors Corporation,General Motors Technical Center,Warren, Michigan 48090; Mr. Louis C. Lundstrom
Executive Director
Environmental Activities Staff
General Motors Corporation
General Motors Technical Center
Warren
Michigan 48090;

Dear Mr. Lundstrom:#This is in reply to your letter of may 11, 1973 asking for confirmation of your interpretation of paragraph S7.9 of Standard No. 105a in term of General Motors' air vacuum power brake.#Your interpretation is correct. Your system with its 'two separate and independent energy sources in the power head...is equivalents to two entirely duplicate systems', and disconnection of one source at a time would be the correct test procedure under S7.9, provided the requirements of S5.1.3 are satisfactorily met under both conditions.#Sincerely,James E. Wilson,Associate Administrator,Traffic Safety Programs;