The several state and county institutions and noninstitutional agencies, the several counties and all departments and agencies of the state shall purchase from the state board all articles or supplies manufactured or produced by institutional labor which are needed by them and shall not purchase any such supplies or articles from another source unless the state board shall first certify on requisition made to it that it cannot furnish the same or the equivalent thereof. The state board as far as practicable shall honor all requisitions.
N.J.S. § 30:4-95