What is the test for setting aside a decision by an arbitrator in a personal injury case?

Under s. 58(2)(a), I must give considerable deference to the decision of the Arbitrator. I can only set aside his decision if I find it to be patently unreasonable. This means that the decision must be what has been described as “openly, evidently, and clearly irrational”, such as where there is no evidence to support the findings. It is not open to me to second-guess conclusions drawn from the evidence considered by the Arbitrator or to substitute different findings of fact or inferences: see Gichuru v. Palmar Properties, 2011 BCSC 827, which discusses this.