Hawthorne Municipal Code Art. 2 General Noise Restrictions

§ 9.34.030. Exterior noise standards.¶

Except as provided for in this chapter, no person shall, at any location within the city, create any noise or allow the creation of any noise on property owned, leased, occupied or otherwise controlled by such person, which causes the energy-equivalent noise level (Leq, dBA) to exceed the noise standards established in subsection A of this section for the receiving land use type where the measurement is taken. Measurement details are provided in Section 9.34.050 below.

A. The maximum permissible sound levels by receiving land use shall apply as shown in Table N-1:

Table N-1: Noise Level Permissible by Receiving Land Use

Land Use Type 2, 3	Time Interval	Allowable Noise Level, Leq (dBA) 1	Allowable Noise Level, Leq (dBA) 1
Land Use Type 2, 3	Time Interval	15-minute continuous measurement period	5-minute continuous measurement period
Residential	7:00 a.m. to 10:00 p.m.	60	65
Residential	10:00 p.m. to 7:00 a.m.	50	55
Commercial	7:00 a.m. to 10:00 p.m.	65	70
Commercial	10:00 p.m. to 7:00 a.m.	60	65
Manufacturing or Industrial	Anytime	70	75

Notes:

1	If the measured ambient noise level at the time of a complaint investigation exceeds the identified permissible noise level for that zone, the allowable noise standard shall be the ambient noise level.
2	For each land use type, the allowable exterior equivalent noise level shall be reduced by five dB for impulsive or simple tone noise, or for noises consisting of speech or music.
3	For situations where the source land use type differs than the receptor land use type, then the maximum allowable exterior equivalent noise level for the entire receiving parcel shall be the average of the noise standards of the two land use types.

(Ord. 2169 § 3, 2019)

Exceptions & meaning →

§ 9.34.040. Interior noise standards.¶

Except as provided for in this chapter, no person shall at any location within the city create any noise or allow the creation of any noise on property owned, leased, occupied or otherwise controlled by such person, which causes the energy-equivalent noise level (Leq, dBA) to exceed the noise standards established in subsection A of this section for the receiving land use type where the measurement is taken. Measurement details are provided in Section 9.34.050 below.

A. The interior noise standards for residential dwelling units within residential zones or areas for noise generated by sources outside the dwelling unit are presented in Table N-2.

Table N-2: Interior Noise Standards

Land Use Type 2	Time Interval	Allowable Noise Level, Leq (dBA) 1 ; 5-minute continuous measurement period
Residential (single- or multi-family)	7:00 a.m. to 10:00 p.m.	45
Residential (single- or multi-family)	10:00 p.m. to 7:00 a.m.	40

Notes:

1	If the measured ambient noise level at the time of a complaint investigation exceeds the identified permissible noise level for that zone, the allowable noise standard shall be the ambient noise level.
2	The allowable exterior equivalent noise level shall be reduced by five dB for impulsive or simple tone noise, or for noises consisting of speech or music.

(Ord. 2169 § 1, 2019)

Exceptions & meaning →

§ 9.34.050. Measurement procedures.¶

A. General Measurement Protocols. Any noise level measurements made pursuant to the provisions of this chapter shall be based on a reference sound pressure of twenty microPascals as measured with a sound level meter using the A-weighted network (scale) at slow response. Sound level meters meeting the Type 1 or Type 2 specifications of ANSI Standard S1.4-1983 (R2006) [or latest revision] are acceptable for collecting data. Equivalent-energy (Leq) noise level measurements are to be taken at any location at the property impacted by the noise, as selected at the discretion of the community noise officer or designee. A violation of this chapter shall occur if the noise standards set forth in this chapter are exceeded for the noise zone where the measurement is taken.

B. Noise Complaint Response. Upon receipt of a complaint, the noise control officer or designee(s) may investigate and assess whether the alleged noise levels exceed the noise standards set forth in this chapter. The investigation may consist of a measurement and the gathering of data required to comply with such code section, and a deadline date for such compliance, and shall warn that if a subsequent inspection or sound level measurement discloses the continued existence of such violation, further action will be taken to adequately define the noise problem, and shall include the following:

Type of noise source.
Location of noise source.
Time period during which the noise source was reported as being in violation of city standards.
Duration of noise produced by noise source.
Date, time, and precise location of the noise measurement survey.

C. Exterior Measurements. Utilizing the A-weighting scale of the sound level meter and the "slow" meter response, the noise control officer shall measure the noise level at a position(s) at the complainant's property line. In general, the microphone shall be located approximately five feet above the ground and ten feet or more from the nearest reflective surface, where possible. However, in cases where another elevation is appropriate or if it is not practical to avoid reflective surfaces, such deviations shall be documented as to the rationale for the alternative position.

D. Interior Measurements. Interior noise measurements shall be made within the affected residential unit. The measurements shall be made at a point at least four feet from the wall, ceiling, or floor nearest the noise source, with windows in the normal seasonal configuration.

(Ord. 2169 § 3, 2019)

Exceptions & meaning →