Section 5. The board of directors of an industrial development financing authority shall elect from among its directors a chairman and a vice-chairman, and may employ counsel, an executive director who shall not be subject to section nine A of chapter thirty or to chapter thirty-one who shall be ex officio secretary of the authority, a treasurer who may be a member of the authority and such other officers, agents and employees as it deems necessary or proper, and shall determine their qualifications, duties and compensation, and may delegate to one or more of its directors, agents or employees such powers and duties as it deems necessary or proper for the carrying out of any action determined upon by it. So far as practicable an authority shall make use of the services of the agencies, officers and employees of the city or town in which it is organized, and such city or town shall, if so requested, make available such services.

Each member of the board before entering upon his duties shall take an oath before the city or town clerk to administer the duties of his office faithfully and impartially, and a record of such oaths shall be filed in the office of said clerk.

The secretary shall keep a record of the proceedings of the board and shall be custodian of all books, documents and papers filed with the board and of the minute book or journal of the board and of its official seal. He shall have authority to cause copies to be made of all minutes and other records and documents of the board and to give certificates under the official seal of the board to the effect that such copies are true copies, and all persons dealing with an authority may rely upon such certificates.

Three members of the board shall constitute a quorum and the affirmative vote of three members of the board shall be necessary for any action taken by the board. No vacancy in the membership of the board shall impair the right of a quorum to exercise all the rights and perform all duties of the board.

Any documentary materials or data whatsoever made or received by any director, officer, agency or employee of the authority or the governing body of a municipality and consisting, or to the extent that such materials or data consist of trade secrets or commercial or financial information regarding the operation of any business conducted by an applicant for any form of assistance which the municipality is empowered to render or regarding the competitive position of such applicant in a particular field of endeavor, shall not be deemed public records of the municipality and specifically shall not be subject to the provisions of section ten of chapter sixty-six. Any discussion or consideration of such trade secrets or commercial or financial information may be held by the authority or governing body in executive sessions closed to the public notwithstanding the provisions of section twenty-three B of chapter thirty-nine, but the purpose of any such executive session shall be set forth in the official minutes of the authority or the governing body, as the case may be, and no business which is not directly related to such purpose shall be transacted nor shall any vote be taken during such executive session.

The board shall have full authority to manage the properties and business of the authority and to prescribe, amend and repeal by-laws, rules and regulations governing the manner in which the business of the authority may be conducted, and the powers granted to it may be exercised.