Okla. Stat. tit. 47, § 47-11-204: Flashing signals

A. Whenever an illuminated red or yellow signal is used in a

traffic sign or signal it shall require obedience by vehicular

traffic as follows:

1. Flashing red (stop signal). When a red lens is illuminated

with rapid intermittent flashes, drivers of vehicles shall stop

before entering the nearest crosswalk at an intersection or at a

limit line when marked, or, if none, then before entering the

intersection, and the right to proceed shall be subject to the

requirements of law applicable after making a stop at a stop sign.

2. Flashing yellow (caution signal). When a yellow lens is

illuminated with rapid intermittent flashes, drivers of vehicles may

proceed through the intersection or past such signal only with

caution.

B. This section shall not apply at railroad grade crossings.

Conduct of drivers of vehicles approaching railroad grade crossings

shall be governed as set forth in Section 11-701 of this title.