Where the mandate of an arbitrator terminates under RCW 7.05.140 or 7.05.150 or because of the arbitrator's withdrawal from office for any other reason or because of the revocation of the arbitrator's mandate by agreement of the parties or in any other case of termination of the arbitrator's mandate, a substitute arbitrator shall be appointed according to the rules that were applicable to the appointment of the arbitrator being replaced.
RCW 7.05.160