In cases where the arbitrator must refuse to resolve a dispute or be replaced, it is specified in Clause 1, Article 42 Commercial Arbitration Law 2010 as follows:

Change of Arbitrator

1. The arbitrator must refuse to resolve the dispute, the parties have the right to request to change the Arbitrator to resolve the dispute in the following cases:

a) The arbitrator is a relative or representative of a party;

b) The arbitrator has relevant interests in the dispute;

c) There are clear grounds showing that the Arbitrator is not impartial and objective;

d) Have been a mediator, representative, or lawyer of any party before submitting the dispute to arbitration, unless otherwise approved in writing by the parties.

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Accordingly, the arbitrator must refuse to resolve the dispute or be replaced in one of the cases specified in Clause 1, Article 42 above. There are cases where the arbitrator is a relative or representative of one party.

Therefore, when the arbitrator is a relative of a party in a commercial dispute, he must refuse to resolve this dispute.