First. Disputes within jurisdiction of Mediation Board The parties, or either party, to a dispute between an employee or group of employees and a carrier may invoke the services of the Mediation Board in any of the following cases: (a) A dispute concerning changes in rates of pay, rules, or working conditions not adjusted by the parties in conference. (b) Any other dispute not referable to the National Railroad Adjustment Board and not adjusted in conference between the parties or where conferences are refused. The Mediation Board may proffer its services in case any labor emergency is found by it to exist at any time. In either event the said Board shall promptly put itself in communication with the parties to such controversy, and shall use its best efforts, by mediation, to bring them to agreement. If such efforts to bring about an amicable settlement through mediation shall be unsuccessful, the said Board shall at once endeavor as its final required action (except as provided in paragraph third of this section and in section 160 of this title) to induce the parties to submit their controversy to arbitration, in accordance with the provisions of this chapter. If arbitration at the request of the Board shall be refused by one or both parties, the Board shall at once notify both parties in writing that its mediatory efforts have failed and for thirty days thereafter, unless in the intervening period the parties agree to arbitration, or an emergency board shall be created under section 160 of this title, no change shall be made in the rates of pay, rules, or working conditions or established practices in effect prior to the time the dispute arose. Second. Interpretation of agreement In any case in which a controversy arises over the meaning or the application of any agreement reached through mediation under the provisions of this chapter, either party to the said agreement, or both, may apply to the Mediation Board for an interpretation of the meaning or application of such agreement. The said Board shall upon receipt of such request notify the parties to the controversy, and after a hearing of both sides give its interpretation within thirty days. Third. Duties of Board with respect to arbitration of disputes; arbitrators; acknowledgment of agreement; notice to arbitrators; reconvening of arbitrators; filing contracts with Board; custody of records and documents The Mediation Board shall have the following duties with respect to the arbitration of disputes under section 157 of this title: (a) On failure of the arbitrators named by the parties to agree on the remaining arbitrator or arbitrators within the time set by section 157 of this title, it shall be the duty of the Mediation Board to name such remaining arbitrator or arbitrators. It shall be the duty of the Board in naming such arbitrator or arbitrators to appoint only those whom the Board shall deem wholly disinterested in the controversy to be arbitrated and impartial and without bias as between the parties to such arbitration. Should, however, the Board name an arbitrator or arbitrators not so disinterested and impartial, then, upon proper investigation and presentation of the facts, the Board shall promptly remove such arbitrator. If an arbitrator named by the Mediation Board, in accordance with the provisions of this chapter, shall be removed by such Board as provided by this chapter, or if such an arbitrator refuses or is unable to serve, it shall be the duty of the Mediation Board, promptly, to select another arbitrator, in the same manner as provided in this chapter for an original appointment by the Mediation Board. (b) Any member of the Mediation Board is authorized to take the acknowledgement of an agreement to arbitrate under this chapter. When so acknowledged, or when acknowledged by the parties before a notary public or the clerk of a district court or a court of appeals of the United States, such agreement to arbitrate shall be delivered to a member of said Board or transmitted to said Board, to be filed in its office. (c) When an agreement to arbitrate has been filed with the Mediation Board, or with one of its members, as provided by this section, and when the said Board has been furnished the names of the arbitrators chosen by the parties to the controversy it shall be the duty of the Board to cause a notice in writing to be served upon said arbitrators, notifying them of their appointment, requesting them to meet promptly to name the remaining arbitrator or arbitrators necessary to complete the Board of Arbitration, and advising them of the period within which, as provided by the agreement to arbitrate, they are empowered to name such arbitrator or arbitrators. (d) Either party to an arbitration desiring the reconvening of a board of arbitration to pass upon any controversy arising over the meaning or application of an award may so notify the Mediation Board in writing, stating in such notice the question or questions to be submitted to such reconvened Board. The Mediation Board shall thereupon promptly communicate with the members of the Board of Arbitration, or a subcommittee of such Board appointed for such purpose pursuant to a provision in the agreement to arbitrate, and arrange for the reconvening of said Board of Arbitration or subcommittee, and shall notify the respective parties to the controversy of the time and place at which the Board, or the subcommittee, will meet for hearings upon the matters in controversy to be submitted to it. No evidence other than that contained in the record filed with the original award shall be received or considered by such reconvened Board or subcommittee, except such evidence as may be necessary to illustrate the interpretations suggested by the parties. If any member of the original Board is unable or unwilling to serve on such reconvened Board or subcommittee thereof, another arbitrator shall be named in the same manner and with the same powers and duties as such original arbitrator. (e) Within sixty days after June 21, 1934, every carrier shall file with the Mediation Board a copy of each contract with its employees in effect on the 1st day of April 1934, covering rates of pay, rules, and working conditions. If no contract with any craft or class of its employees has been entered into, the carrier shall file with the Mediation Board a statement of that fact, including also a statement of the rates of pay, rules, and working conditions applicable in dealing with such craft or class. When any new contract is executed or change is made in an existing contract with any class or craft of its employees covering rates of pay, rules, or working conditions, or in those rates of pay, rules, and working conditions of employees not covered by contract, the carrier shall file the same with the Mediation Board within thirty days after such new contract or change in existing contract has been executed or rates of pay, rules, and working conditions have been made effective. (f) The Mediation Board shall be the custodian of all papers and documents heretofore filed with or transferred to the Board of Mediation bearing upon the settlement, adjustment, or determination of disputes between carriers and their employees or upon mediation or arbitration proceedings held under or pursuant to the provisions of any Act of Congress in respect thereto; and the President is authorized to designate a custodian of the records and property of the Board of Mediation until the transfer and delivery of such records to the Mediation Board and to require the transfer and delivery to the Mediation Board of any and all such papers and documents filed with it or in its possession.

(May 20, 1926, ch. 347, § 5, 44 Stat. 580; June 21, 1934, ch. 691, § 5, 48 Stat. 1195; June 25, 1948, ch. 646, § 32(a), 62 Stat. 991; May 24, 1949, ch. 139, § 127, 63 Stat. 107.)