s 18 Appointment of substitute arbitrator
18.—(1) Where an arbitrator ceases to hold office, the parties are free to agree —(a) whether and if so how the vacancy is to be filled; (b) whether and if so to what extent the previous proceedings should stand; and (c) what effect (if any) his or her ceasing to hold office has on any appointment made by him or her (alone or jointly). (2) If or to the extent that there is no such agreement, the following subsections apply. (3) Section 13 (appointment of arbitrators) applies in relation to the filling of the vacancy as in relation to an original appointment. (4) The arbitral tribunal (when reconstituted) must determine whether and if so to what extent the previous proceedings should stand. (5) The reconstitution of the arbitral tribunal does not affect any right of a party to challenge the previous proceedings on any ground which had arisen before the arbitrator ceased to hold office. (6) The ceasing to hold office by the arbitrator does not affect any appointment by him or her (alone or jointly) of another arbitrator, in particular any appointment of a presiding arbitrator.