27 C.F.R. § 40.532
The appropriate TTB officer may approve methods of operation other than as specified in this subpart, where it is determined that an emergency exists and the proposed variations from the specified requirements are necessary, and provided that the proposed variations will not hinder the effective administration of this subpart and will not be contrary to any provision of law. Variations from requirements granted under this section are conditioned on compliance with the procedures, conditions, and limitations set forth in the approval of the application. Failure to comply in good faith with such procedures, conditions, and limitations will automatically terminate the authority for such variations, and the manufacturer of processed tobacco thereupon must fully comply with the prescribed requirements of the regulations from which the variations were authorized. Authority for any variation may be withdrawn whenever in the judgment of the appropriate TTB officer the effective administration of this subpart is hindered by the continuation of such variation. Where a manufacturer desires to employ such variation, the manufacturer must submit a written application to do so to the appropriate TTB officer. The application must describe the proposed variations and set forth the reasons therefor. Variations may not be employed until the application has been approved. Any authorization of the appropriate TTB officer under this section shall be retained as part of the manufacturer's records, in accordance with this subpart.
27 C.F.R. § 40.532