The operation of the pool shall at all times be subject to the supervision and regulation of the commissioner. The commissioner, or any deputy or examiner, or any person whom he shall appoint, shall have the power of visitation and examination into the affairs of the pool and free access to all the books, papers and documents that relate to the business of the pool, may summon and qualify witnesses under oath, and may examine officers, agents or employees or any other person having knowledge of the affairs, transactions or conditions of the pool.