; and (E) by adding at the end the following: (18) vehicle that performs partial driving automation does not include a commercial motor vehicle (as defined in section 31101). ; and (2) by adding at the end the following: (c) Revisions to certain definitions (1) If SAE International (or its successor organization) revises the definition of any of the terms defined in paragraph (1), (6), or (14) of subsection (a) in Recommended Practice Report J3016, it shall notify the Secretary of the revision. The Secretary shall publish a notice in the Federal Register to inform the public of the new definition unless, within 90 days after receiving notice of the new definition and after opening a period for public comment on the new definition, the Secretary notifies SAE International (or its successor organization) that the Secretary has determined that the new definition does not meet the need for motor vehicle safety, or is otherwise inconsistent with the purposes of this chapter. If the Secretary so notifies SAE International (or its successor organization), the existing definition in subsection (a) shall remain in effect. (2) If the Secretary does not reject a definition revised by SAE International (or its successor organization) as described in paragraph (1), the Secretary shall promptly make any conforming amendments to the regulations and standards of the Secretary that are necessary. The revised definition shall apply for purposes of this chapter. The requirements of section 553 of title 5 shall not apply to the making of any such conforming amendments. (3) Pursuant to section 553 of title 5, the Secretary may update any of the definitions in paragraph (1), (6), or (14) of subsection (a) if the Secretary determines that materially changed circumstances regarding highly automated vehicles have impacted motor vehicle safety such that the definitions need to be updated to reflect such circumstances. .