Section 7. For the purpose of enforcing the provisions of this chapter, carriers engaged in commerce, and persons storing or receiving hazardous substances in commerce or holding such hazardous substances so received shall, upon the request of an officer or employee duly designated by the commissioner acting under authority of a search warrant duly issued by a court of competent jurisdiction, permit such officer or employee at reasonable times, to have access to and to copy all records showing the movement in commerce of any such hazardous substances, or the holding thereof during or after such movement, and the quantity, shipper, and consignee thereof.