(1) A person shall not be employed as a conductor on a railroad freight train in this state without having 2 years’ prior experience as a brakeman or conductor on a freight or passenger train on a line of road. A person shall not be employed as a conductor on a passenger train in this state without having 1 year’s prior experience as a conductor of a freight or passenger train on a line of road.

  (2) A person shall not be employed as a flagperson on a railroad train in this state without having 3 months’ prior experience as a yard or road brakeman on a yard, freight, or passenger train on a line of road.

  (3) A railroad company by its officers, agents, or employees shall not knowingly engage or employ any person to act in the capacity of conductor or flagperson in violation of this act.

  (4) Nothing in this section shall be construed to apply in the case of the disability of a conductor or flagperson or in case of an accident or wreck of a railroad train.

  (5) The provisions of this section shall not apply to any railroad company within this state or the receiver or lessee thereof, whose line of railway is less than 30 miles in length, nor shall anything herein contained relieve any railroad company from the negligence of any of its employees. If a railroad company is unable to hire a sufficient number of persons having the experience for the respective positions specified in this act, at the average rate of wages paid by said company during the next preceding year, it shall be considered a substantial compliance with this act if the company employs from among such persons as are available those having the highest qualifications as to experience and efficiency.

  (6) The department shall enforce this section.