Del Norte County, CA Noise Ordinances: Industrial Noise (2026)

The county's noise ordinance protects residential property from industrial and equipment noise by measuring the sound at the affected residence rather than at the source. The ordinance defines a 'fixed noise source' as 'a stationary device which creates sounds while fixed or motionless, including but not limited to industrial and commercial machinery and equipment, pumps, fans, compressors, generators, air conditioners and refrigeration equipment.' Whatever the source, it is unlawful to create noise that exceeds the residential exterior standard (55 dB(A) day / 50 dB(A) night, reduced 5 dB(A) for tonal or impact noise) when measured on another residential property, under the same tiered duration rules, with an absolute cap at the standard plus 20 dB(A). The ordinance does exempt certain operational categories: emergency machinery and work, equipment used to protect agricultural crops from frost or adverse weather, mobile noise sources tied to agricultural operations within set hours, and agricultural pest-control equipment used under the Agricultural Commissioner's permits. Anything preempted by state or federal law is also exempt. Larger or permitted industrial uses may additionally face noise conditions through Del Norte County Community Development's land-use and permitting process. These rules apply in the unincorporated area; Crescent City handles industrial noise within city limits.