Noise monitoring, control, and compliance practices at several construction sites in Southern California

Noise protection for residential neighborhoods, commercial properties, and wildlife habitats near construction sites is achieved to varying degrees within a maze of local, state, and federal regulations. Standards for a given site typically include noise limits for public nuisance under the municipal ordinance, but a project may also be subject to more restrictive requirements emanating from conditions of approval from a discretionary permit and the environmental review process. Sometimes, goals or provisions of the municipality’s noise element to the general plan are a factor. Sometimes, only noise monitoring is required, for documentation or to determine if noise is a problem. For wildlife, federal or state agencies may have established limits applicable to habitats of certain sensitive, endangered, or threatened species, during nesting season. Noise limits for constructing a subway access in Los Angeles require measurement of maximum noise level (Lmax), while noise limits for grading a park in San Diego use hourly average sound level (Leq). Different limits apply to intermittent versus continuous noise, to different times of day, and to different land uses. Noise reduction may be attained by means such as sound‐attenuation barriers, certification of equipment noise emission prior to use, or operational controls.