The director through his duly authorized representatives and agents, including any proration zone agent who is in charge of a marketing program, shall have access, solely for the purposes of investigating possible violations of any marketing program, to the records of every producer, dealer, distributor, public or private property transporatation agency, and handler of a commodity as to which a marketing program has been instituted. He shall have at all times free and unimpeded access to any building, yard, warehouse, store, or transportation facility or other place in which any commodity under a marketing program is kept, stored, handled, or transported. All information which is obtained is confidential and shall not be disclosed unless required in a judicial proceeding.