(1) A person who is approached in connection with a possible appointment as an arbitrator is to disclose any and all circumstances likely to give rise to doubts as to their impartiality or independence. Arbitrators are under obligation, also after they have been appointed and until the arbitral proceedings have come to an end, to disclose such circumstances to the parties without undue delay unless they have already so informed the parties previously.
(2) An arbitrator may be challenged only if circumstances exist that give rise to justifiable doubts as to their impartiality or independence, or if they do not meet the prerequisites agreed to by the parties. A party may challenge an arbitrator whom they have themselves appointed, or in the appointment of whom the party has participated, solely for reasons of which the party became aware only after the appointment was made.