Interpretation ID: aiam0869
President
Monroe Standard
Inc.
118 Harding Way West
Galion
OH 44833;
Dear Mr. Maison: This is in reply to your letter of September 25, 1972, regarding th warning signal required under S5.1.5 of Motor Vehicle Safety Standard No. 121, Air Brake Systems.; Your reading of the second sentence of S5.1.5 is partially in error. I the visible low pressure warning signal is provided with a companion audible signal, the visible signal does not have to be within the driver's forward field of view. Under S5.1.5 a manufacturer may choose to install a visible signal within the driver's forward field of view, in which case he may omit the audible signal, or to install the signal outside the driver's forward field of view, in which case he must provide an audible signal. If a manufacturer provides a signal within the forward field of view, he may choose to provide an audible signal as well, but the section does not require him to do so.; Sincerely, Richard B. Dyson, Assistant Chief Counsel