45 U.S.C. § 160a

section 553 of title 5The Mediation Board shall have the authority from time to time to make, amend, and rescind, in the manner prescribed by , and after opportunity for a public hearing, such rules and regulations as may be necessary to carry out the provisions of this chapter.

section 553(b) of title 5The requirements of subsection (a) shall not apply to any rule or proposed rule to which the third sentence of applies.