17. Every user 14 years of age or over has right of access to his record. However, the institution may deny him access to it temporarily if, on the advice of his attending physician or the physician designated by the executive director of the institution, communication of the record or any part thereof would likely be seriously prejudicial to the user’s health. In that case, the institution, on the recommendation of the physician, shall determine the time at which the record or the part thereof to which access has been denied can be communicated to the user, and notify him thereof.