Paragraph 17

The arbiter shall, in awarding expenses, take into consideration the reasonableness or unreasonableness of the claim of either party whether in respect of amount or otherwise, and any unreasonable demand for particulars or refusal to supply particulars, and generally all the circumstances of the case, and may disallow the expenses of any witness whom he considers to have been called unnecessarily and any other expenses which he considers to have been incurred unnecessarily.