[NPC Clearinghouse]

"Good Neighbors Keep Their Noise to Themselves"

Boulder County, CO Noise Ordinance
(NPC posted this April 2004)



ORDINANCE NO. 92-28

AN ORDINANCE PERTAINING TO THE REGULATION
OF NOISE ON PUBLIC AND PRIVATE PROPERTY

CHAPTER 1.01

SECTION 1.01.010

Declaration of Policy.

It is hereby declared to be the policy of the County of Boulder that the peace, health, safety and welfare of its citizens require protection from excessive, unnecessary and unreasonable noise. It is the intention of this ordinance to control such noise.

SECTION 1.01.020

Definitions.

As used in this ordinance, the following words shall have the following meanings:

A. "Residential area" means an area of single or multi-family dwellings where businesses may or may not be conducted in such dwellings. This includes areas where multiple unit dwellings, high-rise apartment districts and redevelopment districts are located. A residential area includes areas containing limited accommodations for transients such as motels and hotels, and residential areas with limited office development, but it does not include retail shopping facilities. "Residential Area" includes educational facilities, hospitals, nursing homes, and similar institutions, and parks and open space. Undeveloped areas adjacent to residential areas constitute a residential area for purposes of this ordinance, notwithstanding the zoning classification under the Zoning Resolution of the County.

B. "Property used for commercial business purposes" means an area where offices, clinics and the facilities needed to serve them are located; an area with local shopping and service establishments located within walking distance of the residents served; a tourist-oriented area where hotels, motels and gasoline stations are located; a large integrated regional shopping center; a business strip along a main street containing offices, retail businesses, and commercial enterprises; a central business district; or a commercially dominated area with limited multiple unit dwellings.

C. "Property used for manufacturing or industrial purposes" means an area where manufacturing, processing or fabrication of any commodity, storage and warehousing, wholesale sales of equipment, supplies and materials, repair, rental and servicing of commodities, research laboratories, motor vehicle repair and servicing, and similar activities are conducted.

D. "Agricultural equipment which is used on a farm or ranch in the production of agricultural products" means any type of vehicle, machine, or device used on a farm or ranch, as those terms are defined in subsections (3.5) and (13.5) of C.R.S. §39-1 -102, for planting, growing, and harvesting agricultural products or for raising or breeding livestock for the primary purpose of obtaining a monetary profit.

E. "Vehicle" means any device which is capable of moving itself, or being moved, from place to place upon wheels or endless tracks; but such term does not include any farm tractor or any implement of husbandry designed primarily or exclusively for use and used in agricultural operations or any device moved by muscular power, or moved exclusively over stationary rails or tracks or designed to move primarily through the air.

F. "Motorcycle" means every vehicle designed to travel on not more than three wheels in contact with the ground, but does not include trail bikes, dirt bikes, minibikes, go-carts, golf carts, and similar vehicles which are not designed or approved for use on public roads and highways.

G. "Muffler" means a device consisting of a series of chambers or baffle plates or other mechanical design for the purpose of receiving exhaust gas from an internal combustion engine, and which is effective in reducing noise.

H. "dB(A)" means a sound level in decibels measured on the "A" scale of a standard sound level meter having characteristics defined by the American National Standards Institute, publication S1.4-1971.

I. "Ambient Noise Level" means the lowest sound level repeating itself during a six-minute period as measured with a sound level meter. The minimum sound level shall be determined with the noise source at issue silent, and in the same location as the measurement of the noise level of the source at issue.

J. "Decibel" is a unit used to express the magnitude of a change in sound level. The difference in decibels between two sound pressure levels is twenty times the common logarithm of the ratio of that sound pressure level to a reference level of 2X10- 5N/m2 (Newton's/meter squared).

SECTION 1.01.030

Excessive Sound Levels Prohibited.

No person shall operate any type of vehicle, machine, or device, or carry on any activity, or promote or facilitate the carrying on of any activity which makes sound in excess of the levels specified in Sections 1.01.050 of this ordinance.

SECTION 1.01.040

Measurement of Sound Level.

A. Sound from a vehicle operating on a public road or highway, including the sound of amplified music coming from such vehicle, shall be measured at a distance of fifty feet from the center of the lane of travel.

B. Sound from a vehicle operating on private property or public property which is not a road or highway, including the sound of amplified music coming from such vehicle, shall be measured at a distance of fifty feet or more from such vehicle.

C. Sound from a non-vehicular source shall be measured at a distance of ten feet from the property line of the property where such sound is radiating, except that where the noise source is located on public property owned by a governmental entity, the sound shall be measured at a distance of ten feet from the property line or fifty feet from the noise source, whichever is less. The sound of amplified music from a non-moving vehicle on private property or public property which is not a road or highway shall be considered "sound from a non-vehicular source."

D. Sound shall be measured on the "A" weighting scale on a sound level meter of standard design and quality and characteristics established by the American National Standards Institute.

E. For purposes of this ordinance, measurements with sound level meters shall be made when the wind velocity at the time and place of such measurement is not more than five miles per hour or twenty-five miles per hour with a wind screen.

F. For all sound level measurements, consideration shall be given to the effect of the ambient noise level created by the encompassing noise of the environment from all sources at the time and place of such sound level measurement.

SECTION 1.01.050

Prohibited Noise Levels.

A. Sound from a vehicle being operated on a public road or highway with the following speed limits shall not exceed the following as measured on the "A" weighting scale dB(a):

Type of Vehicle Speed Limit of 35 mph or less Speed Limit of more than 35 mph
Motorcycle manufactured before 1/1/73 82 dB(A) 86 dB(A)
Motorcycle manufactured on or after 1/1/73 80 dB(A) 84 dB(A)
Vehicle with a manufacturer's gross vehicle rating of 10,000 lbs. or more, and any combination of vehicles towed by such vehicle 86 dB(A) 88 dB(A)
All other vehicles 80 dB(A) 84 dB(A)

B. Sound from a vehicle being operated on private property or public property which is not a road or highway shall not exceed the following as measured on the "A" weighting scale dB(A):

All vehicles: 78 dB(A)

C. Sound from a non-vehicular source located in a residential area, shall not exceed the following limits:

7:00 a.m. until 7:00 p.m.7:00 p.m. until 7:00 a.m. of the same day: 55 dB(A) of the following day: 50 dB(A)

D. Construction projects in residential areas shall not exceed the following noise levels for the period within which construction is to be completed pursuant to any applicable construction permit issued by Boulder County, or if no time limitation is imposed, then for a reasonable period of time for completion of project:

7:00 a.m. until 7:00 p.m.7:00 p.m. until 7:00 a.m.of the same day: 80 dB(A)of the following day: 75 dB(A)

E. Periodic, impulsive, or shrill noises are hereby declared unlawful when such noises are at or above a sound level of five dB(A) less than those listed in sections 1.01.050(A), (B), (C), and (D) above.

SECTION 1.01.060

Exceptions.

The provisions of Sections 1.01.030, 1.01.040 and 1.01.050 of this ordinance shall not apply to:

A. The use of property for purposes of conducting speed or endurance events involving motor or other vehicles, but such exception is effective only during the specific period of time within which such use of property is authorized by the political subdivision or governmental agency having lawful jurisdiction to authorize such use.

B. The use of property for the purpose of manufacturing, maintaining, or grooming machine-made snow.

C. The use of property by the state, or any political subdivision of the state, or any of their lessees, licensees, or permittees, for the purpose of promoting, producing, or holding cultural, entertainment, athletic, or patriotic events, including, but not limited to, concerts, music festivals, and fireworks displays.

D. Property used for manufacturing, industrial, or commercial business purposes.

E. Public utilities regulated pursuant to Title 40, C.R.S.

F. Oil and gas production subject to the provisions of Article 60 of Title 34, C.R.S.

G. Operation of aircraft or other activities which are subject to federal law with respect to noise control.

H. Any authorized emergency vehicle, when responding to an emergency call or acting in time of emergency.

I. The sound made by animals.

J. The sound made by the sounding of the horn of any vehicle as a danger warning signal or by the sounding of any burglar, fire, personal safety or other warning device.

K. Activities conducted pursuant to a special use permit issued by the county, unless noise is not addressed by the special use permit.

L. The sound made by a lawnmower, snowblower, or other hand or power tool of no more than five horsepower, between the hours of 7 a.m and 10 p.m.

M. The sound made by agricultural equipment which is used on a farm or ranch in the production of agricultural products.

SECTION 1.01.070

Vehicle Muffler Required.

A. No person shall operate anywhere in unincorporated Boulder County any vehicle that is not equipped with a muffler in constant operation.

B. No person shall operate any vehicle in which a muffler is not properly maintained to prevent any noise in excess of the noise emitted when the muffler was originally installed by the manufacturer of the vehicle.

SECTION 1.01.080

Muffler Modification Prohibited.

No person shall operate anywhere in unincorporated Boulder County any vehicle having a muffler that has been equipped or modified with a cutoff, bypass, or any similar device or modification.

SECTION 1.01.190

Violations and Penalties.

Any person who violates any of the provisions of this ordinance commits a Class 2 Petty Offense. The penalty assessment procedure provided in Section 16-2-201, C.R.S. may be followed by the arresting law enforcement officer for any such violation of this ordinance. Any person who is convicted of a violation of any of the provisions of this ordinance shall be punishable by a fine of $30.00 for each separate violation, plus customary court costs when applicable. A graduated fine schedule for repeat offenses by the same individual within one year shall apply: a $30.00 increase for each recurring offense, beginning at $30.00 to a maximum of $300.00.

SECTION 1.01.100

Effective Date

This ordinance shall take effect and be in force beginning on the 30th day after publication in the Longmont Times Call.

ADOPTED this 14th day of January, 1992.

BOARD OF COUNTY COMMISSIONERS OF BOULDER COUNTY, COLORADO

Homer Page, Chair

Ronald K. Stewart, Vice-Chair

Sandy Hume

NPC Menu Bar NPC Home Page Support NPC Ask NPC Search the NPC Home Page NPC QuietNet NPC Resources NPC Hearing Loss and Occupational Noise Library NPC Noise News NPC Law Library NPC Library