Rancho Palos Verdes City Council




DATE: AUGUST 17, 2004



Review and provide direction regarding whether Staff should prepare a more comprehensive noise control ordinance.


Council Member Long has expressed interest in discussing the adoptoin of an ordinance to establish more comprehensive noise controls in the City. Noise ordinances are typically drafted in either a subjective nuisance standard approach with no specific decibel standards or with very specific decibel standards that define acceptable or unacceptable noise levels. This report analyzes the advantages and disadvantages associated with each type of ordinance, followed by a summary of the City’s existing Municipal Code provisions related to noise regulation.


Although decibel standards appear to be more objective and enforceable, enforcement actions often are unsuccessful because of challenges to the evidence supporting the case on the grounds that the equipment was not properly calibrated or the personnel operating the equipment was not properly trained. Due to the costs associated with obtaining the equipment, ongoing maintenance of the equipment, and training of Staff and the Sheriff’s Deputies, Staff recommends that if the City Council wants to adopt more comprehensive noise regulations, that a nuisance-based ordinance be utilized rather than a decibel-based approach.


Local governments are often faced with the question of how best to regulate noise in the community to protect the general health, safety and welfare. Enactment of such regulations is well within the City’s police powers, but the manner of regulation varies among different jurisdictions. For purposes of this report, noise regulations are divided into two categories: those with reasonableness standards and those with decibel specific standards.

Regulations with "Reasonableness" Standards

Many jurisdictions adopt noise regulations based on a reasonableness standard. Such regulations prohibit noise that is "unreasonably loud," "unusual," "disturbing," "loud and raucous" or "excessive." Although such ordinances could be subject to challenge on the basis of vagueness, such challenges should be rejected if the ordinance gives fair notice of the practice to be avoided, and provides reasonably adequate standards to guide enforcement. Courts tend to find that terms used in an ordinance are not impermissibly vague if their meaning can be objectively ascertained by reference to common experiences of mankind. Provided it is drawn neutrally (that is, without reference to the content of the sound) and narrowly enough to guide enforcement, an ordinance prohibiting "unreasonably loud" noise will likely survive any vagueness or overbreadth challenge to its constitutionality.

The specific language of any descriptive noise ordinance may leave the ordinance open to a vagueness challenge. However, if properly drafted, such an ordinance would place the reasonable person on notice for the conduct that is prohibited. Courts have overwhelmingly refused to find descriptive ordinances impermissibly vague. In fact, the United States Supreme Court has upheld against vagueness attacks ordinances forbidding "loud and raucous" noises that "disturb or tend to disturb the peace and good order" or noises that disturb schools in session, and California courts have upheld ordinances prohibiting "excessive" and unusual noise. In addition, courts have found that the mere existence of a more scientific way of measuring sound does not require the use of that scientific metric in a noise ordinance.

Thus, the fact that it is possible to make an ordinance more precise by including a specific decibel standard does not, by itself, prevent a City from enacting the more general, descriptive ordinance prohibiting "unreasonably loud," or similarly described noise.

As for the disadvantages of employing this type of regulatory scheme, there is always the possibility that such a standard will be challenged for its vagueness. Despite case law affirming the constitutionality of noise ordinances employing descriptive regulations, a court could find a specific ordinance too vague, depending on the language used.

Regulations with Decibel Specific Standards

Many jurisdictions have opted to regulate excessive noise by adopting ordinances that prohibit the creation of sound exceeding a certain level, typically measured in decibels (dB) from a particular location, such as the property line or an exterior wall of an adjacent structure.

The clear benefit of such a regulatory scheme is the fact that decibels can be measured with relative precision, allowing staff to clearly identify whether a particular noise event exceeds the permitted level. The limits on decibel emission would be written into the ordinance, and because they are easily understood, citizens and others are on notice of the standards.

However, a number of potential problems arise with such a regulatory scheme. First, regulations that set a specific decibel threshold may have the unintended effect of prohibiting otherwise reasonable noises. For example, a regulation that prohibits the making of noise that exceeds ten decibels above the ambient level in residential zones may prohibit noise resulting from an outdoor party or children playing. The City could create exemptions for certain noises, but it may be difficult, considering the limitless number of sounds that occur. These regulations may also be subject to a challenge based on arbitrariness, since they require that the City specify a number of decibels, and establishing such a number necessarily involves some choice.

Another potential drawback to enacting this type of regulation is the equipment that is required to accurately measure decibels. In addition to the necessity of having a sound level meter and other appropriate hardware, the City would need to maintain the equipment on a regular basis in order to verify its accuracy. And, in order to determine if the standard is being exceeded, the equipment will have to be made available at the site of the noise complaint, which from a practical standpoint may be problematic with short noise events, or events that have ceased by the time the equipment arrives at the scene. Further, the City would need to hire qualified staff to measure decibel output and enforce the ordinance, or existing City staff would require training in the use of the equipment. This would include training of Sheriff’s Deputies, since they are likely to be called to address noise complaints involving activities such as loud parties.

Because the accuracy of sound level tests is affected by factors including background noise, weather, wind velocity, and the direction of the sound, City staff and Sheriff’s Deputies would need to be trained in factors affecting sound measurement. Defects in any of these requirements opens any enforcement action that is based upon such evidence to legal and evidentiary challenges regarding the validity of the facts upon which a violation is asserted.

Thus, while noise ordinances using a decibel-based standard seem attractive because of their precision, they present a number of drawbacks due to the cost of obtaining equipment, keeping the equipment properly calibrated, and the cost of providing the training to City Staff or Deputies who will be using the equipment.


The Rancho Palos Verde Municipal Code currently contains a number of separate provisions that regulate or limit noise production in the City. These provisions include the following:

Code Section



Prohibition on persistent animal noises that disturb the peace.


Noise Controls applicable to solid waste collection


Unruly Parties and Gathering; recovery of law enforcement expenses


Limitation on Off-road vehicle operation that disturbs the peace


Attached Unit Development Standards to attenuate noise and vibration

17.08.030 C.

Home occupation standards prohibiting activities injurious to neighboring properties for reasons of noise

17.12.030 F.

Limitation on commercial uses regarding deliveries, trash pick-up, parking lot trash sweepers, operation of machinery or mechanical equipment can exceed sixty-five (65) dBA, as measured from the closest property line shall only be allowed on commercial properties which abut a residential district, between the hours of seven a.m. and seven p.m., Monday through Sunday.

17.26.020 E.

Institutional Zone permitted uses; ancillary uses only if adverse noise impact (and other impacts) will not result.

17.26.040 F.

Institutional Zone- deliveries, trash pick-up, parking lot trash sweepers, operation of machinery or mechanical equipment can exceed sixty-five (65) dBA, as measured from the closest property line shall only be allowed on commercial properties which abut a residential district, between the hours of seven a.m. and seven p.m., Monday through Sunday, unless modified by a CUP

17.28.040 I

Cemetery Zone- deliveries, trash pick-up, parking lot trash sweepers, operation of machinery or mechanical equipment can exceed sixty-five (65) dBA, as measured from the closest property line shall only be allowed on commercial properties which abut a residential district, between the hours of seven a.m. and seven p.m., Monday through Sunday, unless modified by a CUP

17.40.070 D.

Automotive Service Stations Overlay Control District – business hours restrictions and limitation on noise to 65 decibels at property line(s) shared with residential property; mechanical car washes not to exceed 65 decibels at property line of any adjacent residential property

17.48.030 E.3. b

65 DB limitation on minor structures and mechanical equipment

17.58.020 A. 9.; B. 11.

Recycling Centers – noise levels limited to no more than 65 decibels as measured from closest property line

17.58.030 C. 9.

Recyclable material collection areas – adjacent development and uses to be protected from noise impact


Conditional Use Permit Standards and conditions to protect against noise impacts


Special Use Permit Standards and conditions to protect against noise impacts

17.74.070 A. 12.

Residential Planned Development Permit - Special Use Permit Standards and conditions to protect against noise impacts

17.60.040 G. 4.

Grading Permits – conditions of approval to address noise impacts of grading activities

17.76.080 C. 1. e and f.

Noise controls convenience stores including 65 decibel limit on mechanical equipment noise measured at nearest property line; minimization of noise from building

17.76.130 E. 4.

Geologic Investigation Permits – approvals to be conditioned to mitigate noise impacts

17.76.140 C. 7.

Bed and Breakfasts – noise and other disturbances related to the use is prohibited

17.76.150 D. 5.

Small Wind Energy Systems - Noise levels for the system shall be no greater than either sixty decibels measured at the closest neighboring inhabited dwelling or any existing maximum noise levels in the general plan, whichever is lower. The noise levels established by this subsection shall not apply during short-term events such as utility outages and severe windstorms.

The City’s existing noise regulations are a hybrid of the two approaches. Many of the provisions are based on a subjective reasonableness criteria rather than decibel specific standards, with some exceptions related to such things as mechanical equipment.


The City of New York, although maintaining a hybrid set of noise regulations, is also shifting away from its conventional decibel limit approach and toward a simplified "plainly audible" standard. A press release discussing the proposed changes in the New York noise code is attached.


Based on the reduced expense and the relatively easier enforcement processes, Staff recommends that the City opt for a narrowly drafted descriptive ordinance without establishing strict decibel standards.


Adoption of a decibel specific ordinance would necessitate acquisition of a decibel-monitoring device, along with staff training and ongoing maintenance costs. Decibel meters are available at a range of prices upwards to $5,000.00 per unit. However, further research would be necessary to determine the cost of a decibel meter that would produce results that a court would likely accept as evidence of a code violation. Staff training and calibration costs also accrue. However, no significant operation costs would be expected if a reasonableness standard ordinance were adopted.


In addition to Staff’s recommendation, the following alternatives are available for the City Council’s consideration:

  1. The City Council may direct Staff to prepare a decibel specific ordinance for consideration by the Planning Commission and the City Council.
  2. The City Council may direct Staff to prepare a hybrid ordinance with some decibel specific standards, but primarily with reasonableness standards, and remand the draft Ordinance back to Staff for further review and refinement.
  3. The City Council may decide to take no action, thereby maintaining in place the existing regulations.

Respectfully submitted:

Carol Lynch

City Attorney


Les Evans

City Manager

Attachment: New York City Press Release dated June 7, 2004