Section 67-6-529 - Exemption certificate for railroad track materials and locomotive radiators(a) Railroads seeking to make purchases of railroad track materials or locomotive radiators subject to the exemption provided in § 67-6-340 shall apply to the commissioner for a certificate. This application shall be made upon forms provided by the commissioner, and shall require information deemed necessary by the commissioner to establish that the applicant is a railroad making purchases of railroad track materials or locomotive radiators for use outside this state. The certificate may be revoked by the commissioner at any time, if the commissioner finds that the holder no longer meets the conditions precedent for the exemption.(b) Railroads making purchases subject to the exemption provided in part 3 of this chapter shall keep records of all such purchases, establishing to the satisfaction of the commissioner that railroad track materials or locomotive radiators purchased were not used in Tennessee, but were removed from this state for use and consumption outside this state.