Agreements by employees purporting to waive or to modify their rights under this chapter shall be void as contrary to public policy, except that a waiver or modification of rights in favor of the Secretary shall be valid for purposes of enforcement of this chapter. ( Pub. L. 97–470, title V, § 506 , Jan. 14, 1983 , 96 Stat. 2598 .) Statutory Notes and Related Subsidiaries Effective Date Section effective 90 days from Jan. 14, 1983 , see section 524 of Pub. L. 97–470 , set out as a note under section 1801 of this title . CFR Title Parts 29 500