Every manufacturer of new motor vehicles or new motor vehicle engines, and every manufacturer of new motor vehicle or engine parts or components, and other persons subject to the requirements of this part or part C, shall establish and maintain records, perform tests where such testing is not otherwise reasonably available under this part and part C (including fees for testing), make reports and provide information the Administrator may reasonably require to determine whether the manufacturer or other person has acted or is acting in compliance with this part and part C and regulations thereunder, or to otherwise carry out the provision of this part and part C, and shall, upon request of an officer or employee duly designated by the Administrator, permit such officer or employee at reasonable times to have access to and copy such records.

Any records, reports, or information obtained under this part or part C shall be available to the public, except that upon a showing satisfactory to the Administrator by any person that records, reports, or information, or a particular portion thereof (other than emission data), to which the Administrator has access under this section, if made public, would divulge methods or processes entitled to protection as trade secrets of that person, the Administrator shall consider the record, report, or information or particular portion thereof confidential in accordance with the purposes of section 1905 of title 18. Any authorized representative of the Administrator shall be considered an employee of the United States for purposes of section 1905 of title 18. Nothing in this section shall prohibit the Administrator or authorized representative of the Administrator from disclosing records, reports or information to other officers, employees or authorized representatives of the United States concerned with carrying out this chapter or when relevant in any proceeding under this chapter. Nothing in this section shall authorize the withholding of information by the Administrator or any officer or employee under the Administrator’s control from the duly authorized committees of the Congress.