Serious irregularity means an irregularity of one or more of the following kinds which the court considers has caused or will cause substantial injustice to the applicant—
failure by the tribunal to comply with section 33 (general duty of tribunal);
the tribunal exceeding its powers (otherwise than by exceeding its substantive jurisdiction: see section 67);
failure by the tribunal to conduct the proceedings in accordance with the procedure agreed by the parties;
failure by the tribunal to deal with all the issues that were put to it;
any arbitral or other institution or person vested by the parties with powers in relation to the proceedings or the award exceeding its powers;
uncertainty or ambiguity as to the effect of the award;
the award being obtained by fraud or the award or the way in which it was procured being contrary to public policy;
failure to comply with the requirements as to the form of the award; or
any irregularity in the conduct of the proceedings or in the award which is admitted by the tribunal or by any arbitral or other institution or person vested by the parties with powers in relation to the proceedings or the award.
The leave of the court is required for any appeal from a decision of the court under this section.