; or (3) certain emergency circumstances, as defined by the Secretary by regulation. (h) Delegation Notwithstanding section 90303(b), and except for the process and procedures required by section 90703(b), the Secretary may delegate safety oversight functions to the Administrator. 90502. Resolution of disputes concerning air traffic services charges and fees (a) Authority To request Secretary’s determination (1) In general The Secretary shall issue a determination as to whether a charge or fee assessed by the Corporation for the use of air traffic services in United States airspace or international airspace delegated to the United States is correct if a written complaint for such determination is filed with the Secretary by an air traffic services user not later than 60 days after the air traffic services user receives an assessment or invoice from the Corporation. (2) Treatment of interest and penalties In this section, the terms charge and fee include any interest and penalty relating thereto. (b) Procedural regulations At least 270 days before the date of transfer, the Secretary shall publish in the Federal Register final regulations, policy statements, or guidelines establishing the procedures for acting upon written complaints filed under subsection (a)(1) and requests of the Corporation pursuant to subsection (e)(3). (c) Determination of correctness In determining under subsection (a)(1) whether a charge or fee is correct, the Secretary shall determine only if the charge or fee is consistent with approved charges or fees pursuant to section 90313. (d) Decisions by Secretary The final regulations, policy statements, or guidelines required in subsection (b) shall provide for the following: (1) Not later than 90 days after an air traffic services user files with the Secretary a written complaint relating to an assessed or invoiced air traffic services charge or fee, the Secretary shall issue a final order determining whether the charge or fee is correct. (2) Not later than 30 days after such complaint is filed