Any person employed upon any railroad as engineer, conductor, baggage-master, brakeman, switchman, fireman, bridge-tender, flagman, or signalman, or having charge of the regulation or running of trains upon any railroad, in any manner whatever, who either becomes or is intoxicated or who is impaired due to the unlawful use of a controlled substance while engaged in the discharge of his duties, is guilty of a misdemeanor. If any person so employed does any act or neglects any duty, by reason of such intoxication or illegal drug use, which act or neglect causes the death of, or bodily injury to, any person or persons, that person so employed is guilty of a

felony.