Since 1974, the Department of Defense has been using the Day-Night Average Sound Level (Ldn) noise descriptor. Noise Exposure Levels are classified into three levels. Noise Exposure Level N3 (75 Ldn or higher) is the area of greatest impact. Noise Exposure Level N2 (65 to 74 Ldn) is the area of moderate impact. Noise Exposure Level N1 (below 65 Ldn) is the area of least impact. Emerald Isle is primarily in the 60 to 65 Ldn zone which means properties within these areas will experience a low to moderate impact from aircraft noise. Residents, property owners, visitors and prospective property owners should be aware of these factors.
Is My Property in an Accident Potential Zone or a Noise Zone? (PDF)