49 CFR 1510.15 - Accounting and auditing requirements.
(a) Direct air carriers and foreign air carriers must establish and maintain an accounting system to account for the security service fees imposed, collected, refunded and remitted. The accounting records must identify the airports at which the passengers were enplaned.
(b) Each direct air carrier and foreign air carrier that collects security services fees from more than 50,000 passengers annually must provide for an audit at least annually of its security service fee activities or accounts.
(c) Audits pursuant to paragraph (b) of this section must be performed by an independent certified public accountant and may be of limited scope. The accountant must express an opinion on the fairness and reasonableness of the direct air carrier's and foreign air carrier's procedures for collecting, holding, and remitting the fees. The opinion must also address whether the quarterly reports required in § 1510.17 fairly represent the net transactions in the security service fee accounts.