Okla. Stat. tit. 66, § 66-125b: Warning signs

Whenever said barricading device shall be constructed or

installed and maintained and operated, the public authorities having

jurisdiction and control over the highway or street at such point

shall erect and maintain a reflector warning sign with appropriate

words thereon. If said barricading device is located at a railroad

crossing, said warning shall be installed and maintained not less

than four hundred (400) feet from the crossing, when said crossing

is located on highways or streets where vehicular traffic is

permitted to travel at speeds in excess of thirty (30) miles per

hour; and not less than two hundred (200) feet from the crossing,

when said crossing is located on highways or streets where vehicular

traffic is permitted to travel at speeds not in excess of thirty

(30) miles per hour. It shall be the duty of the driver of any

vehicle, on approaching such warning sign, to place his vehicle

under such control as to be able to bring such vehicle to a complete

stop at a distance of not less than seventy-five (75) feet in

advance of the crossing. The colliding of a vehicle with the

barricading device at a crossing shall be prima facie evidence that

the driver thereof did not comply with the provisions of this act,

and such driver shall be deemed a reckless driver, and be subjected

to the penalties provided for reckless driving under the motor

vehicle laws of this state, and shall be liable for any damage done

to such barricading device on account of such collision.