42 Pa.C.S. § 7321.4: When subchapter applies.

(a) Subsequent agreements.--This subchapter governs an agreement to arbitrate made on or after the effective date of this subchapter.

(b) Prior agreements.--For an agreement to arbitrate made before the effective date of this subchapter, except as set forth in subsection (c):

(1) If all the parties to the agreement or to the arbitration proceeding agree in a record that this subchapter governs the agreement, this subchapter governs the agreement.

(2) If paragraph (1) does not apply, Subchapter A (relating to statutory arbitration) governs the agreement.

(c) Collective bargaining agreements.--This subchapter shall apply to collective bargaining agreements to arbitrate controversies between employers and employees or their respective representatives only to the extent that the arbitration under this subchapter is consistent with any other statute regulating labor and management relations.