discipline
(2) Discipline .— A railroad carrier or person covered under this section may not discipline, or threaten discipline to, an employee for requesting medical or first aid treatment, or for following orders or a treatment plan of a treating physician, except that a railroad carrier’s refusal to permit an employee to return to work following medical treatment shall not be considered a violation of this section if the refusal is pursuant to Federal Railroad Administration medical standards for fitness of duty or, if there are no pertinent Federal Railroad Administration standards, a carrier’s medical standards for fitness for duty. For purposes of this paragraph, the term “discipline” means to bring charges against a person in a disciplinary proceeding, suspend, terminate, place on probation, or make note of reprimand on an employee’s record.