(1) The Central Government may by order restrict the disclosure of information, whether contained in a document, drawing, photograph, plan, model, or in any other form whatsoever, which relates to, represents or illustrates--
(a) an existing or proposed plant used or proposed to be used for the purpose of producing, developing or using atomic energy, or
(b) the purpose or method of operation of any such existing or proposed plant, or
(c) any process operated or proposed to be operated in any such existing or proposed plant.