Environmental noise surveys assess the ambient noise levels of a specific area, as well as any noise sources deemed inappropriate for the noise environment. Recently, an environmental noise survey was completed to understand the impact of an indoor firing range on adjacent residential properties. Because of the transient nature of the gunfire, day-night equivalent sound pressure level (Ldn), a standard found often in community noise ordinances, was deemed an inappropriate metric to truly determine the intrusiveness of the noise on the surrounding environment. Rather, fast-response maximum sound pressure levels (Lmax) were captured and analyzed in their relation to ambient background noise levels for their effectiveness in translating the impact of the gunfire on adjacent residential properties. Furthermore, multiple frequency-weighting filters were applied to these measurements to fully understand the characteristics of this broadband, high-impact noise. This paper discusses the appropriateness of Lmax when focusing on transient environmental noise levels caused by an indoor firing range as well as how these metrics should be characterized in community noise ordinances.
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