OAR 735-124-0020
Flashing Warning Lights
(1)
Bus shall be equipped with two alternately flashing red lights on the front, at the upper left and right corners above the windshield; and two alternately flashing red lights on the back, at the upper left and right corners above the windows. Lights having a minimum of 7" diameter measured across the face of lens are strongly recommended.(2)
Each signal lamp shall be mounted with its axis substantially parallel to the longitudinal axis of the vehicle.(3)
Lamps shall be of a type approved by Transportation Safety and shall flash alternately at a rate of 60 to 120 cycles per minute.(4)
Lamp lenses shall be red in color as specified by current SAE standards.(5)
Lamps shall be controlled by a manually operated switch with a positive “off” and “on” position and mounted in such a position that the switch can be easily reached by the driver while seated in a normal driving position. Wiring of this switch through the ignition switch is not permitted. This shall be the only switch that controls the flashing warning lights. (Door switch or springloaded switch not permitted.)(6)
There shall be a visible means of giving a clear or unmistakable indication to the driver when the lamps are turned on. This visible indication shall be wired into the circuit so that it will flash when the warning lights flash and it shall be within the direct view of the driver when seated in a normal driving position, and shall have an illuminated area of at least 5⁄8" diameter.(7)
Area around lens of each alternately flashing red warning light and extending outward approximately 3“ may be painted black. In installations where there is no flat vertical portion of body immediately surrounding entire lens of lamp, circular or square band of black approximately 3” wide immediately below and to both sides of lens, may be painted on body or background area against which signal lamp is seen.
Source:
Rule 735-124-0020 — Flashing Warning Lights, https://secure.sos.state.or.us/oard/view.action?ruleNumber=735-124-0020
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