14 C.F.R. § 161.201 – Scope.

(a) This subpart applies to:
1. (1) An airport imposing a noise or access restriction on the operation of Stage 2 aircraft, but not Stage 3 aircraft, proposed after October 1, 1990.
2. (2) An airport imposing an amendment to a Stage 2 restriction, if the amendment is proposed after October 1, 1990, and reduces or limits Stage 2 aircraft operations (compared to the restriction that it amends) or affects aircraft safety.
(b) This subpart does not apply to an airport imposing a Stage 2 restriction specifically exempted in § 161.7 or a Stage 2 restriction contained in an agreement as long as the restriction is not enforced against aircraft operators that are not parties to the agreement.