Wyo. Stat. § 37-9-801
It shall be unlawful for any owner or operator of a railroad running through or within the boundaries of the state of Wyoming and engaged in the business of common carrier to operate for or transport its employees in a motor car which is not equipped with a reasonably substantial top for the protection of said employees from rain, snow, sleet and hail, and equipped with a transparent windshield sufficient in width and height to reasonably protect said employees, which windshield shall be of safety glass and such car shall also be equipped with a permanently placed electric headlamp of sufficient candlepower as to render visible at a distance of three hundred (300) feet in advance of such car under ordinary atmospheric conditions, any obstruction, landmark, warning sign or grade crossing on such railroad. Said car shall also be equipped with one (1) red electric light on the rear end thereof with sufficient candlepower as to be visible at a distance of three hundred (300) feet under ordinary atmospheric conditions, and such car shall also be equipped with a windshield wiper that will remove rain, snow and sleet from the windshield on such car while such car is moving and said windshield shall be so devised that the driver of said car can start or stop said windshield wiper while he is driving the car.
W.S. 37-9-801