“A-weighted sound level” means the sound level in decibels as measured on a sound level meter using the A-weighting network. The level so read is designated dB(a) or dBA.

“Ambient noise level” means the all-encompassing noise level associated with a given environment, being a composite of sounds from all sources, excluding the alleged offensive noise, at the location and approximate time at which a comparison with the alleged offensive noise is to be made.

“City” means the incorporated area of the City of Larkspur.

“Decibel” means a unit for measuring the amplitude of a sound, equal to twenty times the logarithm to the base ten of the ratio of the pressure of the sound measured to the reference pressure, which is twenty micropascals.

“Emergency or utility power outages” means any City, County or State declared emergency, and interruption of utility power due to preventive utility shut-off measures or due to damage to utility infrastructure from accidents, earthquakes, fires, floods, storms, winds, or their acts; or any event deemed to be an emergency by City officials to preserve and protect life and property.

“Emergency work” means the use of any machinery, equipment, vehicle or manpower for the performance of an emergency response, or emergency repair, in an effort to protect, maintain, provide or restore safe conditions and/or public utilities in a community or for the citizenry, on either public or private property.

“Fixed noise source” means a stationary device that creates sounds while fixed or motionless, including, but not limited to, machinery, equipment, pumps, fans, compressors, air conditioners, refrigeration equipment and stationary generators, used for residential, agricultural, industrial or commercial purposes.

“Hertz (Hz)” means a unit of measurement of frequency numerically equal to cycles per second.

“Holidays” means those days designated or observed as federal holidays and the day after Thanksgiving.

“Impulsive noise” means sounds of short duration, usually less than one second, with an abrupt onset and rapid decay. Examples of sources of impulsive sound include explosions, drop-forge impacts, the discharge of firearms, and dog barking.

“Noise level” means the A-weighted sound pressure level in decibels obtained by using a sound level meter with a reference pressure of twenty micropascals. The units of measurement shall be designated as dBA.

“Person” means a person, firm, association, co-partnership, joint venture, corporation or any entity, public or private in nature.

“Portable generator” means any UL-listed diesel or gas-fired generator not connected to a building’s electrical system and intended to provide power during emergency work.

“Property line” means a line along the ground surface, and its vertical extension which separates the real property owned by one person from that owned by another person.

“Pure tone” means any sound that can be judged as audible as a single pitch or a set of single pitches such as might be produced by a whistle or a musical instrument. For the purposes of this chapter, a pure tone shall exist if the one-third octave band sound pressure level in the band with the tone exceeds the arithmetic average of the sound for center frequencies of five hundred Hz and above, and by eight dB for center frequencies between one hundred sixty and four hundred Hz, and by fifteen dB for center frequencies less than or equal to one hundred twenty-five Hz.

“Routine testing” means the required and routine testing per manufacturers’ recommendations to maintain and keep ready stationary generators; usually on a weekly or monthly schedule and for a time period not to exceed ninety minutes and only between the hours of ten a.m. and four p.m.

“Sound level meter” means an instrument meeting or exceeding American National Standard Institute’s Standard S1.4-1971 for Type 2 sound level meters, or an instrument and the associated recording and analyzing equipment that will provide equivalent data.

“Stationary generator – General use” means any UL 2200-listed natural gas- and/or propane-fired generator permanently installed and connected to the building’s electrical system with building permits issued by the City, and only intended to provide power during emergencies or utility power outages. Generators must not exceed sixty-five to seventy dBA during full speed diagnostics and normal operations when measured in compliance with Larkspur Municipal Code Section 9.54.020 and shall be set back a minimum of ten feet from property lines.

“Stationary generator – Public service buildings, health care providers, or utility provider” means any UL-listed natural gas, diesel or propane fired generator permanently installed and connected to a building or a public utility’s electrical system to provide power during emergencies or utility power outages. Generators must not exceed sixty-five to seventy dBA during full speed diagnostics and normal operations when measured in compliance with Larkspur Municipal Code Section 9.54.020. Generators installed in a commercial or industrial district to power a health care building must be set back a minimum of ten feet from property lines. (Ord. 1048 § 2, 2020; Ord. 1030 § 2(7), 2018; Ord. 1010 § 1, 2016; Ord. 697 § 1 (part), 1983)