The department acting through its mine inspectors shall have full access to every preparation plant and premises of a producer, including railroad cars or railroad sidings, and the storage yard and premises of every retail dealer, and to any railroad car or motor vehicle transporting anthracite wherever the same may be, and shall have the legal right to take samples of anthracite thereat or therefrom for the purpose of testing the same upon paying, or tendering where demanded, the value of the sample so taken, and to examine the weighmaster's certificate or statement of quality accompanying the shipment, as required by this act. They shall have the right to inspect the books and records of every producer, retail dealer, wholesale dealer, municipal weighmaster, and other persons required to keep records by this act, relating to the sale, resale, reweighing, shipment and delivery of anthracite. Such mine inspectors shall make reports of all inspections and tests to the secretary which shall be open to public inspection. The subject inspections, as described herein, shall be made only subsequent to and as a result of a public complaint submitted to the department.