Tustin, CA Noise from Specific Sources: HVAC & Mechanical Noise (2026)

Section 4619 reads narrowly: during a one-year period following the effective date of Ordinance No. 828, the noise level standards in Sections 4614 and 4615 were increased by eight dB(A) for any air-conditioning apparatus or refrigeration system that was already installed before the ordinance took effect on July 21, 1980. That one-year transition ended in 1981, so the section no longer grants any current allowance. Under the definitions in Section 4612, an air conditioner or refrigeration unit is a "fixed noise source," the same category as pumps, fans, compressors and generators, and fixed noise sources are measured against the regular Noise Zone table in Section 4614: 55 dB(A) by day and 50 dB(A) at night in residential Zone 1, 60 dB(A) in commercial Zone 2, and 70 dB(A) in industrial Zone 3, plus the stricter interior figures in Section 4615 when the noise is heard inside a neighboring dwelling.

Measurements follow Section 4620, using a sound level meter at least four feet from the nearest wall, ceiling or floor to the unit. A homeowner or business with a noisy condenser or rooftop compressor gets no special exemption today; the unit has to fit inside the same numeric ceiling as any other fixed equipment on the property.