(c) No charge need to be made for furnishing:
- (1) Unauthenticated copies of any rules, regulations, or decisions of general import,
- (2) Copies to agencies which will aid in the administration of the Davis-Bacon and related acts,
- (3) Copies to contractor associations and labor organizations for general dissemination of the information contained therein, and
- (4) Only occasionally unauthenticated copies of papers and documents.