29 CFR 5.40: Severability.

The provisions of this part are separate and severable and operate independently from one another. If any provision of this part is held to be invalid or unenforceable by its terms, or as applied to any person or circumstance, or stayed pending further agency action, the provision is to be construed so as to continue to give the maximum effect to the provision permitted by law, unless such holding is one of utter invalidity or unenforceability, in which event the provision is severable from this part and will not affect the remaining provisions.