Chapter 16 NOISE*

*Cross reference(s)--Health and sanitation, Ch. 11; parks and recreation, Ch. 18; police, Ch. 19; streets, sidewalks and other public places, Ch. 21; traffic and vehicles, Ch. 24; zoning, Ch. 27.

State law reference(s)--Noise abatement, C.R.S. § 25-12-101 et seq.

----------

The making and creating of excessive, unnecessary or unusually loud noises within the city limits which are prolonged, unusual or unreasonable in their time, place and use are a detriment to the public health, comfort, convenience, safety and welfare of the residents of the city and may cause damage to property or business. The necessity for the provisions and prohibitions contained and enacted in this chapter is declared as a matter of legislative determination and public policy to be in the public interest and for the purpose of securing and promoting the public health, comfort, convenience, safety, welfare and peace and quiet of the inhabitants of the city.

(Code 1962, § 6-11-1)

All terminology used in this chapter shall be consistent with applicable American National Standards Institute publications, or those from successor publications or bodies. For purposes of this chapter, certain words and phrases are defined as follows:

A-weighted sound pressure level means the sound pressure as monitored with a sound level meter using the A-weighted network. The standard notation is dB(A).

Ambient noise level means the sound pressure level of all-encompassing noise associated with a given environment, being usually a composite of sounds from many sources. It is also the sound pressure level exceeded ninety (90) percent of the time based on a sample of at least one (1) minute.

Commercial district means all property located within commercial zones according to the official zoning map of the city.

Construction activities means any and all activity incidental to the erection, demolition, assembling, altering, installing or equipping of buildings, structures, roads or appurtenances thereof, including land clearing, grading, excavation and filling.

Continuous noise means steady or fluctuating noise which exists essentially without interruption during the period of observation.

Decibel means a logarithmic unit of measure often used in measuring magnitudes of sound. The symbol is dB.

Device means any mechanism which is intended to, or which actually produces, audible sound when operated or handled.

Dynamic braking device means a device used primarily on trucks for the conversion of the engine from an internal combustion engine to an air compressor for the purpose of braking without the use of wheel brakes.

Emergency work or emergency vehicle means work made necessary to restore property to a safe condition following a public calamity or work required to protect persons or property from an imminent exposure to danger. An emergency vehicle is a vehicle used in response to a public calamity or to protect persons or property from an imminent exposure to danger.

Industrial district means all property located within the industrial zones according to the official zoning map of the city.

Intermittent noise means a noise whose sound pressure level equals or is less than the ambient noise level two (2) or more times during the period of observation and is greater than the ambient during the remainder of the period.

Motor vehicle means any vehicle such as, but not limited to, passenger cars, trucks, truck-trailers, semitrailers, campers, motorcycles, minibikes, go-carts, snowmobiles, motorboats, racing vehicles, and other devices propelled by mechanical power.

Muffler means any apparatus consisting of baffles, chambers, or acoustical absorbing material whose primary purpose is to transmit liquids or gases while causing a reduction in sound emission at one (1) end. To qualify, such an apparatus must cause a reduction of at least ten (10) dB(A) upon insertion into the system for which it is intended.

Noise means any sound which is unwanted or which causes or tends to cause an adverse psychological or physiological effect on human beings.

Noise disturbance means any sound which annoys or disturbs reasonable persons with normal sensitivity, or which injures or endangers the comfort, repose, health, safety or peace of other persons.

Person means any human being, firm, association, organization, partnership, business, trust, corporation, company, contractor, supplier, installer, user, owner or operator, including any municipal corporation or its officers or employees.

Property boundary means an imaginary line at the ground surface which separates the real property owned by one (1) person from that owned by another person, and its vertical extension.

Public right-of-way means any street, avenue, boulevard, highway, alley, premise or public conveyance which is owned or controlled by a public governmental entity.

Residential district means all property located within residential zones according to the official zoning map of the city.

Sound level meter means an instrument, including a microphone, amplifier, output meter and weighting networks, for the measurement of sound pressure. The output meter reads sound pressure level when properly calibrated and the instrument is of Type 2 or better as specified in the American National Standards Institute Publication Sl. 4-1974, including successor publications.

Stationary noise source means any equipment or facility, fixed or movable, capable of emitting sound beyond the property boundary of the property on which it is located.

(Code 1962, 6-11-2)

Cross reference(s)--Definitions and rules of construction generally, § 1-2.

It shall be unlawful to play, operate or use any device known as a sound truck, loudspeaker or sound amplifier, radio or phonograph, with loudspeaker or sound amplifier or any instrument of any kind or character which emits loud or raucous noises and is attached to and upon any vehicle unless such person in charge of such vehicle shall have first applied to and received permission from the chief of police to operate any such vehicle so equipped.

(Code 1962, § 6-1-29)

State law reference(s)--Traffic and motor vehicles, Ch. 24.

(Code 1962, § 6-11-3)

For purposes of determining and classifying any noise as excessive or unusually loud as declared to be unlawful and prohibited by this chapter, the following test measurements and requirements may be applied; provided, however, a violation of section 16-4 may occur without the following measurements being made:

(Code 1962, § 6-11-4)

It shall be unlawful for any person to operate or permit to be operated any stationary source of noise which creates a sound pressure level which exceeds the limits set forth in table 1 for more than ninety (90) percent of any measurement period. The measurement period shall not be less than a period of two (2) minutes and shall be measured at a distance in accordance with the requirements of section 16-5. When a noise source can be identified and its noise measured in more than one (1) zoning category, the limits of the most restrictive zoning classification shall apply at the boundaries between different zoning classifications. Noise levels for any planned unit development shall conform with table I and shall be determined by the predominant land use as set forth in the planned unit development plan. Table I is as follows:

TABLE I

PERMISSIBLE LEVELS

(Code 1962, § 6-11-5)

TABLE II

MAXIMUM PERMISSIBLE SOUND

PRESSURE LEVELS

(Code 1962, § 6-11-6)

Construction projects shall be subject to the maximum permissible noise levels specified for industrial zones for the period within which construction is to be completed pursuant to any applicable construction permit issued by a proper authority, or if no time limitation is imposed pursuant to such permit, then for a reasonable period of time for completion of the construction project. However, this section shall not prelude emergency work of public service utilities.

(Code 1962, § 6-11-7)

It shall be unlawful for any person to operate or engage a dynamic braking device within the city except for the aversion of imminent danger.

(Code 1962, § 6-11-8)

It shall be unlawful to use or operate a loudspeaker or sound amplifying equipment in a fixed or movable position or mounted upon any motor vehicle upon any street, alley, sidewalk, park, place, public or private property within the city. Nothing in this section shall prohibit the use of speakers or sound amplifying equipment within an enclosed area; provide, however, the noise created from such speakers or sound amplifying equipment shall be subject to the limitations set forth in section 16-6.

(Code 1962, § 6-11-9)

The city manager or his authorized representative has the authority to designate quiet zones within the city, which zones shall be in the vicinity of any school, hospital, institution of learning, court, rest home or other designated area where exceptional quiet is necessary, while the same are in use; provided, however, conspicuous signs shall be placed or displayed in such streets or areas indicating that the same has been designated as a quiet zone. For purposes of this chapter, all property designated quiet zones shall have a maximum permissible steady sound pressure level limit as set forth within table I under section 16-6 for residential use or residential zoning districts. It shall be unlawful for any person to create any loud or excessive noise in excess of the sound pressure level limits set forth for residential zones under section 16-6 within any area that has been designated as a quiet zone pursuant to this section.

(Code 1962, § 6-11-10)

It shall be unlawful for any person to sell, lease, rent or install any device or sell, rent, lease or operate any motor vehicle, engine or mechanical device with a device which when attached to or placed upon such motor vehicle, engine or mechanical device amplifies or increases the noise emitted by it above that emitted by the motor vehicle, engine or mechanical device in its original factory design.

(Code 1962, § 6-11-11)

Noise caused in the performance of emergency work for the immediate safety, health or welfare of the community or individuals of the community or to restore property to a safe condition following a public calamity shall not be subject to the provisions of this chapter. Nothing in this section shall be construed to permit law enforcement, ambulance, fire or other emergency vehicles to make excessive noise in the performance of their duties when such noise is clearly unnecessary.

(Code 1962, § 6-11-12)

Application for a permit for relief from the provisions of this chapter on the basis of undue hardship may be made to the police chief or his duly authorized representative by any person subject to the jurisdiction of this chapter. In administering such application, the police chief or his duly authorized representative shall construe the term "undue hardship" to mean noise caused, which if prohibited, would cause undue hardship to the person responsible for the creation of the noise. In determining whether relief should be granted in the form of a permit pursuant to this section, consideration shall be given to the time of day that the noise is created, the duration of the noise, the loudness of the noise relative to the required limits, whether the noise is temporary or continuous in nature, the extensiveness of the noise and the technical and economic feasibility of bringing such noise source into conformance with the provisions of this chapter.

(Code 1962, § 6-11-13)

Applications for a permit to hold a public event which may violate the provisions of this chapter shall be made to the police chief or his duly authorized representative in accordance with the requirements of section 16-16. Such permit, if issued, shall be valid only at the specified times and dates and only upon the specified conditions noted in such permit.

(Code 1962, § 6-11-14)

Applications for a permit for relief from the provisions of this chapter may be made to the police chief or his duly authorized representative. Any permit granted by the police chief pursuant to this chapter shall be effective only for the location and times designated within the permit and shall be further subject to such limitations with regard to sound pressure levels or equipment limitations as may be set forth in such permit.

(Code 1962, § 6-11-17)

Any person violating any section of this chapter, performing any act which is prohibited or declared unlawful by this chapter or permitting or causing any noise in excess of limits set forth within this chapter shall, upon conviction thereof, be subject to a fine in a sum not to exceed three hundred dollars ($300.00) or to imprisonment not to exceed ninety (90) days, or both such fine and imprisonment.

(Code 1962, § 6-11-15)

As an additional remedy, the operation or maintenance of any noise source in violation of any provisions of this chapter which causes discomfort or annoyance to reasonable persons of normal sensitivity or which endangers the comfort, repose, health, or peace of residents within the city shall be deemed and is declared to be a public nuisance and may be subject to abatement by restraining order or injunction by a court of competent jurisdiction. It shall be presumed, subject to rebuttal, that a person seeking relief from noise disturbance is a reasonable person of normal sensitivity and the burden of proof to show otherwise shall be upon the person or entity against whom relief is sought.

(Code 1962, § 6-11-16)