All corporations, companies or individuals owning, managing or operating any street railway or line in the state of Washington, shall provide, during the rain or winter season, all cars run or used on its or their respective roads with good, substantial and sufficient vestibules, or weather guards, for the protection of the employees of such corporation, company or individual.

The vestibules or weather guards shall be so constructed as to protect the employees of such company, corporation or individual from the wind, rain or snow.