The Board may, by general or special order, delegate, subject to such conditions and limitations, if any, as may be specified in the order, to any Member or Secretary or other officer or employee of the Board or other person authorised by the Board to manage any industrial company or industrial undertaking or any operating agency, such powers and duties [except the powers and duties under sub-sections (2) and (4) of section 16, section 17, sub-sections (3) and (4) of section 19, sub-sections (1) and (4) of section 20, sub-section (3) of section 22 and section 24] under this Act as it may deem necessary.