If the interior noise level reduction attributable to soundproofing does not achieve compatibility under Part 150 or local land-use guidelines, an ______- noise easement should supplement the soundproofing.

• A. avigation
• B. navigation
• C. aviation
• D. airspace

Answer: (A)

When interior noise levels from soundproofing can’t meet Part 150 or local guidelines, a legal instrument that protects the noise environment over time is used. An avigation easement is a property interest that limits or conditions future development to preserve airport noise compatibility and to support the effectiveness of noise abatement measures. It can restrict land-use changes or activities that would worsen exposure, ensuring the noise environment remains manageable even if physical improvements don’t fully achieve compliance. The other terms aren’t the standard instrument used for this purpose in Part 150 contexts.