Noise & Vibration Technical Appendix

Noise & Vibration Technical Appendix Characteristics of Sound Sound is a pressure wave transmitted through the air. When an object vibrates, it radiates part of its energy as acoustical pressure in the form of a sound wave. Sound can be described in terms of amplitude (loudness), frequency (pitch), or duration (time). The standard unit of measurement of the loudness of sound is the decibel (db). The human hearing system is not equally sensitive to sound at all frequencies. Sound waves below 16 Hz are not heard at all and are "felt" more as a vibration. Similarly, while people with extremely sensitive hearing can hear sounds as high as 20,000 Hz, most people cannot hear above 15,000 Hz. In all cases, hearing acuity falls off rapidly above about 10,000 Hz and below about 200 Hz. Since the human ear is not equally sensitive to sound at all frequencies, a special frequency-dependent rating scale is usually used to relate noise to human sensitivity. The A-weighted decibel scale (dba) performs this compensation by discriminating against frequencies in a manner approximating the sensitivity of the human ear. Because of the physical characteristics of noise transmission and noise perception, the relative loudness of sound does not closely match the actual amounts of sound energy. Table 1, Change in Sound Pressure Level, db, presents the subjective effect of changes in sound pressure levels. Typical human hearing can detect changes of approximately 3 dba or greater under normal conditions. Changes of 1 to 3 dba are detectable under quiet, controlled conditions and changes of less than 1 dba are usually indiscernible. A change of 5 dba or greater is typically noticeable to most people in an exterior environment and a change of 10 dba is perceived as a doubling (or halving) of the noise. Table 1 Change in Sound Pressure Level, db Change in Apparent Loudness ± 3 db Threshold of human perceptibility ± 5 db Clearly noticeable change in noise level ± 10 db Half or twice as loud ± 20 db Much quieter or louder Source: Bies and Hansen, Engineering Noise Control, 2009. Point and Line Sources Noise may be generated from a point source, such as a piece of construction equipment, or from a line source, such as a road containing moving vehicles. Because noise spreads in an everwidening pattern, the given amount of noise striking an object, such as an eardrum, is reduced with distance from the source. This is known as "spreading loss." The typical spreading loss for point source noise is 6 dba per doubling of the distance from the noise source. A line source of noise, such as vehicles proceeding down a roadway, would also be reduced with distance, but the rate of reduction is affected by of both distance and the type of terrain over which the noise passes. Hard sites, such as developed areas with paving, reduce noise at a rate of 3 dba per doubling of the distance while soft sites, such as undeveloped areas, open space and vegetated areas reduce noise at a rate of 4.5 dba per doubling of the distance. These E-1

represent the extremes and most areas would actually contain a combination of hard and soft elements with the noise reduction placed somewhere in between these two factors. Unfortunately the only way to actually determine the absolute amount of attenuation that an area provides is through field measurement under operating conditions with subsequent noise level measurements conducted at varying distances from a constant noise source. Objects that block the line of sight attenuate the noise source if the receptor is located within the "shadow" of the blockage (such as behind a sound wall). If a receptor is located behind the wall, but has a view of the source, the wall would do little to reduce the noise. Additionally, a receptor located on the same side of the wall as the noise source may experience an increase in the perceived noise level, as the wall would reflect noise back to the receptor compounding the noise. Noise Metrics Several rating scales (or noise "metrics") exist to analyze adverse effects of noise, including traffic-generated noise, on a community. These scales include the equivalent noise level (L eq ), the community noise equivalent level (CNEL) and the day/night noise level (L dn ). L eq is a measurement of the sound energy level averaged over a specified time period. The CNEL noise metric is based on 24 hours of measurement. CNEL differs from L eq in that it applies a time-weighted factor designed to emphasize noise events that occur during the evening and nighttime hours (when quiet time and sleep disturbance is of particular concern). Noise occurring during the daytime period (7:00 AM to 7:00 PM) receives no penalty. Noise produced during the evening time period (7:00 to 10:00 PM) is penalized by 5 db, while nighttime (10:00 PM to 7:00 AM) noise is penalized by 10 db. The L dn noise metric is similar to the CNEL metric except that the period from 7:00 to 10:00 PM receives no penalty. Both the CNEL and L dn metrics yield approximately the same 24-hour value (within 1 db) with the CNEL being the more restrictive (i.e., higher) of the two. Regulatory Environment State of California Noise Compatibility Standards Table 2, presents a land use compatibility chart for community noise adopted by the California Office of Noise Control. This Table provides urban planners with a tool to gauge the compatibility of land uses relative to existing and future noise levels. Land uses, such as offices and commercial, are "normally acceptable" in exterior noise environments up to 70 dba CNEL and "conditionally acceptable" in areas up to 77.5 dba CNEL. A "conditionally acceptable" designation implies that new construction or development should be undertaken only after a detailed analysis of the noise reduction requirements for each land use type is made and needed noise insulation features are incorporated in the design. By comparison, a "normally acceptable" designation indicates that standard construction can occur with no special noise reduction requirements. E-2

Table 2 Land Use Compatibility for Community Noise Environments CNEL (dba) Land Uses 55 60 65 70 75 80 Residential-Low Density Single Family, Duplex, Mobile Homes Residential- Multiple Family Transient Lodging, Motels, Hotels Schools, Libraries, Churches, Hospitals, Nursing Homes Auditoriums, Concert Halls, Amphitheatres Sports Arena, Outdoor Spectator Sports Playgrounds, Neighborhood Parks Golf Courses, Riding Stables, Water Recreation, Cemeteries Office Buildings, Businesses, Commercial and Professional Industrial, Manufacturing, Utilities, Agricultural Normally Acceptable: Specified land use is satisfactory based upon the assumption that any buildings involved are of normal conventional construction, without any special noise insulation requirements. Conditionally Acceptable: New construction or development should be undertaken only after a detailed analysis of the noise reduction requirements is made and the needed noise insulation features included in the design. Conventional construction, but with closed windows and fresh air supply systems or air conditioning will normally suffice. Normally Unacceptable: New construction or development should generally be discouraged. If new construction does proceed, a detailed analysis of the noise reduction requirements must be made and needed noise insulation features included in the design. Clearly Unacceptable: New construction or development generally should not be undertaken. Source: Office of Noise Control, Guidelines for the Preparation and Content of Noise Elements of the General Plan, February 1976. Included in the Governor s Office of Planning and Research, California, General Plan Guidelines, Appendix C, October 2003. E-3

California Building Code Noise standards have been incorporated as part of the California Building Code and California Noise Insulation Standards (Title 24 and 25, California Code of Regulations) and are the noise standards required for new construction in California. The California Administrative Code, Title 24, Part 2 requires that the interior noise levels in multifamily residential uses not exceed 45 dba CNEL or L dn ; this is commonly used as an interior standard for all residential uses. Title 21, Subchapter 6 of the California Code of Regulations (Airport Noise Standards) establishes 65 dba CNEL as the acceptable level of aircraft noise for persons living in the vicinity of airports. Noise-sensitive land uses in locations where the aircraft exterior noise level exceeds 65 dba CNEL are generally incompatible, unless (1) an aviation easement for aircraft noise has been acquired by the airport proprietor or (2) the residence is a high-rise apartment or condominium that has an interior CNEL of 45 dba or less in all habitable rooms despite aircraft noise and an air circulation or air conditioning system, as appropriate. Assembly Bill (AB) 2776 requires any person who intends to sell or lease residential properties within an airport influence area to disclose that fact to the person buying the property. City of Orange Noise Standards City of Orange Noise Land Use Compatibility Standards The City has developed its own land use compatibility standards as shown in Table 3. These standards are based on the parameters from the California Governor s Office of Planning and Research and set forth the normally acceptable conditions. These standards are applicable for land uses exposed to noise levels generated by mobile sources. E-4

Table 3 Maximum Allowable Noise Exposure Transportation Sources Land Uses CNEL (dba) Designations Uses Interior 1, 3 Exterior 2 Estate Low Density Residential Low Density Residential Low Medium Density Residential Medium Density Residential Neighborhood Mixed-use Neighborhood Office Professional Old Towne Mixed-use General Commercial Yorba Commercial Overlay Urban Mixed-Use Urban Office Profession Light Industrial Industrial Public Facilities and Institutions Recreational Commercial Open Space Open Space Park Open Space Ridgeline Resource Area Single-family, duplex, and multiple-family 45 65 Mobile home park N/A 65 Single-family 45 65 Mobile home park N/A 65 Multiple-family, mixed use 45 65 4, 5 Transient lodging motels, hotels 45 65 Sports arenas, outdoor spectator sports N/A N/A Auditoriums, concert halls, amphitheaters 45 N/A Office buildings, business, commercial and professional 50 N/A Manufacturing, utilities, agriculture N/A N/A Schools, nursing homes, day care facilities, hospitals, convalescent 45 65 facilities, dormitories Government Facilities offices, N/A 45 fire stations, community buildings Places of Worship, Churches 45 N/A Libraries 45 N/A Utilities N/A N/A Cemeteries N/A N/A Playgrounds, neighborhood parks N/A 70 Golf courses, riding stables, water recreation, cemeteries Source: City of Orange Noise Element (2010). N/A = Not applicable to specified land use category or designation. Notes: 1. Interior habitable environment excludes bathrooms, closets, and corridors. 2. Exterior noise level standard to be applied at outdoor activity areas; such as private yards, private patio or balcony of a multi-family residence. Where the location of an outdoor activity area is unknown or not applicable, the noise standard shall be applied inside the property line of the receiving land use. 3. Interior noise standards shall be satisfied with windows in the closed position. Mechanical ventilation shall be provided per Uniform Building Code (UBC) requirements. 4. Within the Urban Mixed-Use, Neighborhood Mixed-Use, Old Towne Mixed-Use, and Medium Density Residential land use designations, exterior space standards apply only to common outdoor recreational areas. 5. Within Urban Mixed-Use and Medium Density Residential land use designations, exterior noise levels on private patios or balconies located within 250 feet of freeways (I-5, SR-57, SR-55, SR-22, or SR-241) and Smart Streets and Principal Arterials identified in the Circulation & Mobility Element that exceed 70 db should provide additional common open space. N/A N/A City of Orange Stationary Noise Standards - The City applies the Noise Control Ordinance standards, summarized in Table 4, to non-transportation stationary noise sources. These standards do not gauge the compatibility of developments in the noise environment, but provide restrictions on the amount and duration of noise generated at a property, as measured at the property line of the noise receptor. These noise standards do not apply to noise generated by vehicle traffic, because the state, counties, and cities are pre-empted from E-5

controlling vehicle noise under federal law. The City s Noise Ordinance is designed to protect people from objectionable non-transportation noise sources such as music, construction activity, machinery, pumps, and heating, ventilation, and air conditioning (HVAC) systems. According to Section 8.24.050 of the City s Municipal Code, stationary (non-transportation) noise generated on a property is prohibited from exceeding the maximum sound levels as shown in Table 4 at the property line. Table 4 City of Orange Maximum Exterior Noise Limits (dba) Land Use Time Period L 50 L 25 L 8 L 2 L max 7:00 AM to 10:00 PM 55 60 65 70 75 Residential 10:00 PM to 7:00 AM 50 55 60 65 70 Source: City of Orange Municipal Code. Chapter 8.24.050 Noise. Notes: The noise standards shall be increased by 8 db where the alleged offensive noise source is an air conditioner installed prior to January 19, 1979. In the event that the ambient noise levels exceed the exterior noise limits, the noise standards shall be increased to reflect the ambient noise level; however, the maximum permissible noise level (L max) shall never exceed the maximum ambient noise level. Each of the noise limits specified above shall be reduced by 5 dba for impact or simple tone noise, or for noises consisting of speech or music. City of Orange Construction Noise Standards - The City realizes that the control of construction noise is difficult to control and therefore provides exemptions for this type of noise from the stationary noise limitations of the City s Municipal Code. In addition, the City limits the hours of construction activity to the least noise sensitive portions of the day. According to the City of Orange Municipal Code, Section 8.24.070, construction activities are prohibited between 8:00 PM and 7:00 AM on weekdays and Saturday, and anytime on Sundays and Federal holidays Federal Transit Administration Vibration Criteria The City of Orange has not adopted criteria to address vibration; therefore, the Federal Transit Administration (FTA) is used for this analysis. The FTA provides criteria for acceptable levels of groundborne vibration for various types of land uses that are sensitive to vibration. These criteria can be separated into annoyance effects and architectural damage effects due to vibration. Vibration Annoyance Table 5 shows the FTA and Caltrans vibration criteria to evaluate vibration-related annoyance due to resonances of the structural components of a building. These criteria are based on the work of many researchers that suggested that humans are sensitive to vibration velocities in the range of 8 to 80 Hz. Table 5 Groundborne Vibration Impact Criteria: Human Annoyance Land Use Category Vibration Velocity, in/sec (RMS amplitude) 1 Description Workshop 90 Distinctly felt vibration. Appropriate to workshops and non-sensitive areas Office 84 Felt vibration. Appropriate to offices and non-sensitive areas. Residential Daytime 78 Barely felt vibration. Adequate for computer equipment. Residential Nighttime 75 Vibration not felt, but groundborne noise may be audible inside quiet rooms. Source: FTA 2006 and Caltrans 2004. 1 As measured in 1/3-octave bands of frequency over the frequency ranges of 8 to 80 Hz. E-6

Vibration-Related Architectural Damage Structures amplify groundborne vibration with typical residential structures more affected by ground vibration than heavier buildings. The level at which groundborne vibration is strong enough to cause architectural damage has not been determined conclusively. The most conservative estimates are reflected in the FTA standards, shown in Table 6. Table 6 Groundborne Vibration Impact Criteria: Architectural Damage Building Category PPV (in/sec) I. Reinforced concrete, steel, or timber (no plaster) 0.5 II. Engineered concrete and masonry (no plaster) 0.3 III. Non-engineered timber and masonry buildings 0.2 IV. Buildings extremely susceptible to vibration damage 0.12 Source: FTA 2006. Sensitive Noise Receptors Certain land uses are particularly sensitive to noise and vibration. Noise- and vibration-sensitive uses include land uses where quiet environments are necessary for enjoyment and public health and safety. Residences, schools, guest lodging, libraries, religious institutions, hospitals, nursing homes, and passive recreation areas are generally more sensitive to noise than commercial and industrial land use. The nearest sensitive receptors are the residences surrounding the project site. E-7

References Airnav, LLC. 2016. Airport Information. http://www.airnav.com/airports. Beranek, Leo. Noise and Vibration Control. Revised Edition. Institute of Noise Control Engineering. Washington, D.C. 1988. Bies, David A. and Colin H. Hansen. 2009. Engineering Noise Control: Theory and Practice. 4 th Ed. New York: Spon Press. California Department of Transportation (Caltrans). 2004, June. Transportation- and Construction-Induced Vibration Guidance Manual. Prepared by ICF International. California Department of Transportation (Caltrans). 2006, Traffic Noise Analysis Protocol. California Department of Transportation (Caltrans). 2009, November. Technical Noise Supplement ( TeNS ). Prepared by ICF International. California Department of Transportation (Caltrans). 2004, June. Transportation- and Construction-Induced Vibration Guidance Manual. Prepared by ICF International. California Department of Transportation (Caltrans), Division of Environmental Analysis. 2002, February. Transportation Related Earthborne Vibration (Caltrans Experiences). Technical Advisory, Vibration. TAV-02-01-R9601. Prepared by Rudy Hendricks. City of Orange Municipal Code, primarily Chapter 8.24 City of Orange General Plan Noise Element, 2010. Federal Highway Administration (FHWA). 1978, December. Federal Highway Traffic Noise Prediction Model. United States Department of Transportation Report No. FHWA-RD77-108. Federal Highway Administration (FHWA), 2006. Roadway Construction Noise Model (RCNM), Version 1.0. Federal Highway Administration (FHWA). 2011, July. Noise Compatible Planning, a Federal Approach The Audible Landscape. United States Department of Transportation, Federal Highway Administration, Office of Planning, Environment, & Realty. Accessed at: http://www.fhwa.dot.gov/environment/noise/noise_compatible_planning/federal_approach/au dible_landscape/al04.cfm Federal Transit Administration (FTA). 2006, May. Transit Noise and Vibration Impact Assessment. United States Department of Transportation. FTA-VA-90-1003-06. Governor s Office of Planning and Research. 2003, October. State of California General Plan Guidelines. Harris, Cyril M. Handbook of Acoustical Measurements and Noise Control, Third Edition. Acoustical Society of America. Woodbury, NY. 1998. Thalheimer, E., 2000, Construction Noise Control Program and Mitigation Strategy as the Central Artery/Tunnel Project. Institute of Noise Control Engineering. U. S. Environmental Protection Agency (USEPA). 1978, November. Protective Noise Levels (Condensed Version of EPA Levels Document). EPA 550/9-79-100. See immediately below. U. S. Environmental Protection Agency (USEPA). 1974, March. Information on Levels of Environmental Noise Requisite to Protect Public Health and Welfare with an Adequate Margin of Safety. U.S. EPA Office of Noise Abatement and Control, Washington, D.C. U. S. Environmental Protection Agency (USEPA). 1971, December. Noise from Construction Equipment and Operations, Building Equipment, and Home Appliances. Prepared by Bolt Beranek and Newman, Inc., Cambridge, MA for the U.S. EPA Office of Noise Abatement and Control. Washington, D.C. E-8

City of Orange Noise Element E-9

NOISE INTRODUCTION TO THE NOISE ELEMENT The urban environment contains a variety of noise sources which can affect the way people live and work. Some types of noise are only short-term irritants, like the pounding of a jackhammer or the whine of a leaf blower. These noise sources generally can be controlled through City noise regulations, such as a noise ordinance. However, other noises, like freeway noise, may be permanent fixtures in the community, posing long-term health hazards to community residents. Purpose of this Element In recognition of the fact that excessive or unusual noise can have significant adverse impacts on human health and welfare, the State has developed definitive guidelines for determining community noise levels and for establishing programs aimed at reducing community exposure to noise levels defined to be adverse. The purpose of the Noise Element is to identify noise sources in the community, to describe anticipated future noise levels, and to put forth policies and programs designed to minimize the effects of noise on people living and working in Orange. This element focuses on: Reducing the exposure of existing residences, schools and businesses to freeway noise through the construction of sound walls; Using noise information to formulate land use policy in undeveloped areas of the City; Minimizing the number of new residences constructed within areas with high noise levels; Establishing guidelines for new construction along urban highways, arterials and secondary roadways where noise may be a problem; and Identifying and mitigating intermittent or short-term noise annoyances. Identification of Noise Sources The primary sources of noise in Orange are the freeways which surround the City, the SR-241/261 that traverses the eastern portion of the planning area, and the many arterial roadways which traverse almost all areas of the community. High volumes of traffic on the freeways, toll roads, and arterials such as Tustin Street, Chapman Avenue and Katella Avenue account for ambient noise levels in excess of 65 dba some distance from these transportation routes. Figure N-1 ORANGE GENERAL PLAN N-1 E-10

NOISE displays noise levels as of January 1988 in the form of noise contours. The contours, which are similar to elevation contours contained on a topographic map, present noise exposure information for all areas of the City. The Noise Element Technical Report describes how the contour lines are generated. The freeway, toll road, and roadway noise represent relatively steady, constant noise sources. Periodic sources of noise include train traffic (both Amtrak and freight trains), aircraft over flights into John Wayne Airport, military aircraft traffic (especially helicopter traffic) along the Katella Avenue corridor and over residential neighborhoods in eastern Orange, and the operation of trucks and machinery in the City s industrial district. Noise sources which are not accounted for in Figure N-1 but which can be especially bothersome in quiet residential neighborhoods are such short-term irritants as the loud playing of stereos, the operation of motorized garden equipment and even the shrill sounds of a schoolyard full of school children. Related Plans and Programs Several local, state and federal laws regulate point source noise and establish standards for protecting community residents from excessive noise. City of Orange Noise Ordinance: The City has adopted a noise ordinance (Ordinance 17-74) which establishes interior and exterior noise standards for all residential neighborhoods, schools, churches and hospitals in the City. These standards are presented in the Noise Plan section of this element. Certain temporary activities, such as activities at public parks, construction occurring between the hours of 7:00 a.m. and 9:00 p.m. and school bands are exempt from the noise regulations. Caltrans Sound Walls: The California Department of Transportation (Caltrans), pursuant to Section 215.5 of the State Streets and Highway Code, has established a priority system for erecting noise barriers in the form of sound walls along freeway routes. The program is designed to protect residential uses from excessive freeway noise. In order for a residential neighborhood adjacent to a freeway to qualify for the program, the neighborhood must meet three eligibility criteria as follows: The housing units must have been constructed prior to freeway construction or widening of the freeway; The housing units must be exposed to noise levels equal to or greater than 67 Leq; and Construction of the sound walls must be cost effective. Generally, a cost of $30,000 per housing unit protected is considered reasonable (in 1988 dollars). Any units not meeting all three criteria cannot receive funding from Caltrans. ORANGE GENERAL PLAN N-2 E-11

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NOISE State Noise Insulation Standards: Title 25, Section 1092 of the California Administrative Code sets forth requirements for the insulation of multiple family residential dwelling units from excessive and potentially harmful noise. The State indicates that locating units in areas where exterior ambient noise levels exceed 65 dba is undesirable. Whenever such units are to be located in such areas, the developer must incorporate into building design construction features which reduce interior noise levels to 45 dba CNEL. Scope and Format of Element The Noise Element establishes noise/land use compatibility standards and outlines programs which can be used to achieve these standards. The following section of this element, Noise Element Goals and Policies, sets forth the City s goals for achieving the standards and introduces policies and programs designed to implement the goals. The last section of this element, the Noise Exposure Reduction Plan, elaborates on noise standards and noise mitigation programs. NOISE ELEMENT GOALS AND POLICIES In this element the City establishes one general goal aimed toward reducing the exposure of noise sensitive land uses to excessive and potentially harmful noise. Protecting Residents from Noise GOAL 1.0: The City will continue to recognize the importance of protecting residents from unnecessary and harmful noise. POLICY 1.1: Consider noise impacts in future land use planning and decision making. Implementation 1.1.1: Enforce the noise/land use compatibility standards identified in the General Plan Noise Element. Implementation 1.1.2: Continue to enforce the City s existing noise ordinance to reduce point source noise. Implementation 1.2.3: Review and revise the City s noise ordinance as necessary to ensure compatibility with community noise goals and State and Federal noise standards. POLICY 1.2: Encourage intergovernmental coordination to abate noise emissions. Implementation 1.2.1: Work with the California Department of Transportation to establish noise attenuation barriers along the freeways where noise/land use conflicts exist. POLICY 1.3: Protect identified noise sensitive land uses, especially the residential neighborhoods, from significant noise sources. ORANGE GENERAL PLAN N-5 E-14

NOISE Implementation 1.3.1: Enforce State noise insulation standards for all residential units through the building permit review process. Implementation 1.3.2: Adopt a City ordinance which prohibits the use of motorized leaf blowers within the City limits. POLICY 1.4: Implement programs designed to reduce the noise impacts from motor vehicle traffic. Implementation 1.4.1: Use Police Department resources to enforce regulations related to motor vehicle noise. Implementation 1.4.2: Require noise buffer zones to be incorporated into the design of new subdivisions wherever residential uses abut secondary or arterial roadways or highways. Related Goals and Policies A number of goals and policies contained in the other five General Plan Elements support the goals and policies presented in the Noise Element. Table N-1, the Noise Element Policy Matrix, identifies those goals and policies directed toward implementing noise reduction goals. Table N-1 Noise Element Policy Matrix Issue Area Land Use Housing Circulation Safety Open Space & Conservation Protect Residents from Harmful and Unnecessary Noise 3.0, 9.0, 12.0 8.0 3.0, 5.0 This matrix illustrates the internal consistency of the General Plan by indicating which goals contained in the other five elements reinforce the Noise Element goal of protecting residents from noise. NOISE EXPOSURE REDUCTION PLAN Definition of Noise What is noise? Noise is generally defined as unwanted or intrusive sound. The characteristics of noise are difficult to describe by a single unit of measurement because noise has many components, such as loudness, pitch and duration. Scientists have developed the A-weighted decibel (dba) as a common noise descriptor, and this unit is widely used to indicate the loudness level of a particular sound at a given point in time. Figure N-2 describes and compares the relative loudness of various noise sources. ORANGE GENERAL PLAN N-6 E-15

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NOISE Other forms of noise measurement include the Community Noise Equivalent Level (CNEL) and the Day-Night Level (Ldn). These latter two measurements describe ambient noise levels over a 24- hour period. The Noise Element Technical Report provides a more comprehensive discussion of these measurements of noise, as well as a description of the A-weighted decibel. Noise Standards In order to identify areas where future noise levels may present land use constraints or may threaten public health and welfare, noise standards must first be established. The City hereby adopts two types of noise standards as follows: Noise/land use compatibility standards which will be used to mitigate existing noise ambient problems and to guide future land use decisions; and Point source noise standards for all areas of the City designed to protect residential properties from excessive noise. The noise/land use compatibility standards are those recommended by the State Department of Health Services, modified to reflect the City s established standard for residential areas, as indicated in Figure N-3. Noise standards for point source noise in all areas of the City will continue to be those established in the City s noise ordinance. These standards are as follows: It shall be unlawful for any person at any location within the City to create any noise, or to allow the creation of any noise on property owned, leased, occupied or otherwise controlled by such person, which causes the noise level, when measured on any other residential property, to exceed: 1. The noise standard for a cumulative period of more than 30 minutes in any hour; or 2. The noise standard plus 5 dba for a cumulative period of more than 15 minutes in any hour; or 3. The noise standard plus 10 dba for a cumulative period of more than five minutes in any hour; or 4. The noise standard plus 15 dba for a cumulative period of more than one minute in any hour; or 5. The noise standard plus 20 dba for any period of time. (City Ordinance No. 17-74, Section 9500.5) The noise standard applies to all residential properties in the City. The exterior noise standard is 55 dba between the hours of 7:00 a.m. and 10:00 p.m., and 50 dba between 10:00 p.m. and 7:00 a.m. For interior noises, the standards are 55 dba between 7:00 a.m. and 10:00 p.m., and 45 dba between 10:00 p.m. and 7:00 a.m. ORANGE GENERAL PLAN N-8 E-17

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NOISE Future Noise Environment As indicated in the Introduction to this Element, the primary sources of noise in Orange include the freeways, toll roads, and arterial roadways. These noise sources impact the land uses located along the transportation routes. Figure N-1 illustrates the community noise environment as of January 1988. To determine future levels throughout the community, General Plan land use information and anticipated future traffic volumes were entered into a community noise computer model. Figure N-4 displays future noise contours for the City, assuming buildout of the City proceeds in accordance with General Plan land use policy. Figure N-4 indicates that noise levels may be expected to rise in areas where roadways will experience the greatest increase in traffic volumes over time. Specifically, these areas include The City shopping center area, the industrial/commercial areas along the Santa Ana River at Taft Avenue to Orangewood, and the Tustin Street corridor. Identification of Noise Problem Areas Potential noise problem areas are considered to be those areas where ambient noise levels exceed established noise standards and areas where sensitive land uses are exposed to ambient noise levels in excess of 60 dba. For the most part, the problem areas lie along freeways, toll roads, and arterial and secondary roadways where noise barriers have not been installed. Although the noise contours on Figure N-4 do not indicated noise levels exceeding 60 dba in the eastern portion of the City, beneath the landing pattern for aircraft approaching John Wayne Airport in Newport Beach, some residents in the area find the aircraft noise disturbing. The aircraft noise may be considered an intermittent, recurring noise problem. Military aircraft traffic along the Katella Avenue corridor presents similar problems. An additional noise problem cited by residents Citywide is the noise associated with the operation of hand-held, motorized leaf blowers. Gasoline powered blowers, which are generally used to clear debris from driveways, sidewalks and landscaped areas, generate noise levels in the range of 60 to 85 dba (measured 50 feet from the source). This noise level exceeds the standard established for residential areas for all hours of the day. Noise Mitigation Programs The primary tool used to implement noise policy will be the noise ordinance. The ordinance gives the City authority to regulate noise at its source and thereby protect noise sensitive land uses. Other programs to be used include: ORANGE GENERAL PLAN N-10 E-19

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NOISE Freeway Sound Walls Caltrans has developed a priority list for the installation of sound walls along freeways which abut residential land uses. Residential neighborhoods meeting the program eligibility requirements outlined in the introduction to this element ( Related Plans and Programs ) are placed on the Statewide Priority List in descending order of the neighborhood s priority index. Caltrans uses the following formula to calculate the priority index: Achievable x (Average Future Predicted) x Number of Reduction (in db) ( Noise Level ) Dwelling Units Cost of Wall (in $1000 s) Areas in Orange automatically qualifying for the sound wall program are limited to developments along the Costa Mesa Freeway (State Route 55). These areas, indicated on Figure N-5, are: - The northbound side of SR-55 from Taft Avenue to Meats Avenue; and - Both the northbound and southbound sides of SR-55 from Collins Avenue to Katella Avenue. An additional stretch which may be eligible is the northbound side of SR-55 from Walnut Avenue to Oakmont Avenue Sound wall construction along the Taft to Meats section is scheduled for the 1991 State fiscal year. The remaining sections, however, have priority indices which place them farther down the priority list. The State will not pay for sound wall construction until at least the year 2000. Consistent with the reimbursement provisions of the State Streets and Highways Code, Orange may choose to erect sound walls before the dates scheduled by Caltrans. The City would finance construction of the walls, and Caltrans would reimburse the City in the year improvements were originally scheduled. Because no other freeway sections other than those cited above qualify for the noise barrier program, all other sound walls must be erected at City or private expense. New residential units adjacent to or near freeways may be required to provide such walls to meet the noise/land use compatibility standards outlined in Figure N-4. Enforcement of State Standards As indicated in the introduction to this element, Title 25 of the California Administrative Code establishes exterior and interior noise standards for multi-family residential development. Units established in areas where ambient noise levels exceed 65 dba must incorporate noise reduction features into project design and construction. To reduce exterior noise levels, open space and other outdoor, usable private areas should be shielded from the primary noise source (e.g., a Form atted: Section start: Continuous ORANGE GENERAL PLAN N-13 E-22

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NOISE freeway or railroad track). Insulation must be provided to reduce interior ambient noise levels to 45 dba or lower. The Planning and Building divisions of the City will continue to enforce these regulations. Enforcement of Noise Ordinance The City will continue to enforce the provisions of the noise ordinance. The ordinance will be amended or a new ordinance passed to ban the use of motorized leaf blowers. Sound Walls Along Toll Roads, Arterials and Secondary Roadways All new residential development proposed adjacent to toll roads, arterials and secondary roadways will be required to provide sound walls or combination berms and walls designed to achieve the noise/land use compatibility standards indicated in Figure N-4. Design of Residential Projects Truck Routes Design features incorporated into residential projects can be used to shield residents from excessive noise. For example, bedrooms, balconies and open space areas can be located away from streets and focused toward the interior of a project. The City will develop guidelines to assist developers design structures which respond to noise concerns. Truck traffic generates noise which can disturb residential and other noise sensitive land uses. Heavy trucks will not be permitted to drive through residential neighborhoods. The City may establish signed truck routes or may erect signs prohibiting heavy trucks from driving on designated streets. Air Traffic Noise To lessen the impacts of noise associated with air traffic into John Wayne Airport, the City will participate in regional efforts to require airlines to use quieter aircraft. Also, the City will work with airport officials and surrounding jurisdictions to restore instrument approach patterns (as opposed to visual approach) into the airport. Finally, the City will continue to register noise complaints with the airport s Noise Abatement Office to ensure airport officials are made aware of any noise problems. Military aircraft operations generally affect the eastern portion of the City. The City will continue to work with military officials at the Los Alamitos U.S. Army Airfield to minimize overflights over Orange and to direct any necessary overflights along established transportation or open space corridors. Deleted: Naval Air Station Deleted: and at El Toro ORANGE GENERAL PLAN N-15 E-24

Chapter 8.24 - NOISE CONTROL [2] Sections: Footnotes: --- (2) --- City of Orange Municipal Code Editor's note Ord. No. 1-14, I, adopted August 12, 2014, repealed the former Ch. 8.24, 8.24.010 8.24.110 and enacted a new Ch. 8.24 as set out herein. The former Ch. 8.24 pertained to similar subject matter and derived from Prior Code 9500.1 9500.16; Ord. Nos. 49-74, 17-74, 1-80, and 26-96. 8.24.010 - Policy. A. In order to control unnecessary, excessive and annoying sounds emanating from the City, it is the policy of the City to regulate such sounds generated from all sources as specified in this chapter. The intent of this chapter is to protect residential land uses from unnecessary, excessive and annoying sounds. B. It is determined that certain sound levels are detrimental to the public health, welfare and safety, and contrary to public interest. (Ord. No. 1-14, I, 8-12-14) 8.24.020 - Definitions. The following words, phrases and terms as used in this chapter shall have the meaning as indicated below: A. "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. B. "Adjusted ambient noise level" means the measured ambient noise level plus 3 db (A). Three (3) db (A) is the industry-accepted threshold of human perceptibility for a change in the noise environment. C. "Decibel (db)" means a unit which denotes the ratio between two quantities which are proportional to power: the number of decibels corresponding to the ratio of two amounts of power is ten times the logarithm to the base ten of this ratio. D. "Emergency machinery, vehicle or work" means any machinery, vehicle or work used, employed or performed in an effort to protect, provide or restore safe conditions in the community or for the citizenry, or work by private or public utilities when restoring utility service. E. "Fixed noise source" means a stationary noise source which creates sounds while fixed or motionless, including but not limited to construction equipment, industrial and commercial machinery and equipment, pumps, fans, compressors, generators, air conditioners and refrigeration equipment. F. "Grading" means any excavating or filling of earth material or any combination thereof conducted to prepare a site for construction or other improvements thereon. E-25 Page 1

G. "Hourly Average" (L eq ) means the energy mean or average sound level over a one (1) hour period of time. H. "Impact noise" means the noise produced by the collision of one mass in motion with a second mass which may be either in motion or at rest. I. "Mobile noise source" means any noise source other than a fixed noise source. J. "Noise level" means the "A" weighted sound pressure level in decibels obtained by using a sound level meter at slow response with a reference pressure of twenty (20) micronewtons per square meter. The unit of measurement shall be designated as db(a). K. "Person" means a person, firm, association, co-partnership, joint venture, corporation or any entity, public or private in nature. L. "Recurring impulsive noise" means a noise of short duration, usually less than one (1) second, with an abrupt onset and rapid decay, which occurs repeatedly or in a cyclical manner. Examples include jack hammering, pile driving, or operational noise from a generator or other mechanical equipment that is cyclical in nature. M. "Residential property" means a parcel of real property which is developed and used either in part or in whole for residential purposes, other than transient uses such as hotels and motels. N. "Simple tone noise" means a noise characterized by a predominant frequency or frequencies so that other frequencies cannot be readily distinguished. O. "Sound level meter" means an instrument meeting American National Standard Institute's Standard Sl.4-1983 for Type 1 sound level meters or an instrument and the associated recording and analyzing equipment which will provide equivalent data. P. "Sound pressure level" of a sound, in decibels, means twenty times the logarithm to the base ten of the ratio of the pressure of the sound to a reference pressure, which reference pressure shall be explicitly stated. (Ord. No. 1-14, I, 8-12-14) 8.24.030 - Noise Level Measurement Criteria. Any noise level measurements made pursuant to the provisions of this chapter shall be performed using a sound level meter as defined in Section 8.24.020P. (Ord. No. 1-14, I, 8-12-14) 8.24.040 - Exterior Standards. A. The following noise standards for fixed noise sources, unless otherwise specifically indicated, shall apply to all residential property: Table 8.24.040 Exterior Noise Standards Noise Level Time Period Hourly Average (L eq ) 55 db (A) 7:00 a.m. 10:00 p.m. 50 db (A) 10:00 p.m. 7:00 a.m. Page 2 E-26

Maximum Level 70 db (A) 7:00 a.m. 10:00 p.m. 65 db (A) 10:00 p.m. 7:00 a.m. B. It is unlawful for any person at any location within the City to create any noise, or to allow the creation of any noise on property owned, leased, occupied or otherwise controlled by such person, which causes the noise level when measured on any other residential property to exceed the noise standards identified in Table 8.24.040. For multi-family residential or mixed use developments located within the City's Urban Mixed Use, Neighborhood Mixed Use, Old Towne Mixed Use or Medium Density Residential General Plan land use districts, exterior noise standards shall apply to common recreation areas only and shall not apply to private exterior space (such as a private yard, patio, or balcony). C. In the event the ambient noise level exceeds the noise standards identified in Table 8.24.040 of this section, the "adjusted ambient noise level" shall be applied as the noise standard. In cases where the noise standard is adjusted due to a high ambient noise level, the noise standard shall not exceed the "adjusted ambient noise level", or 70 db (A), whichever is less. In cases where the ambient noise level is already greater than 70 db (A), the ambient noise level shall be applied as the noise standard. D. Each of the noise limits specified in Table 8.24.040 shall be reduced by 5 db(a) for impact or simple tone noises, recurring impulsive noises, or for noises consisting of speech or music. (Ord. No. 1-14, I, 8-12-14) 8.24.050 - Exemptions from Chapter Provisions. The following activities shall be exempted from the provisions of this chapter: A. School bands, school athletic and school entertainment events; B. Outdoor gatherings, public dances, shows, and sporting and entertainment events provided such events are conducted pursuant to any permit requirements established by the City; C. Activities conducted on public parks, public playgrounds, and public or private school grounds; D. Any mechanical device, apparatus or equipment used, related to or connected with emergency machinery, vehicle or work; E. Noise sources associated with construction, repair, remodeling, or grading of any real property, provided said activities take place between the hours of 7:00 a.m. and 8:00 p.m. on any day except for Sunday or a Federal holiday, or between the hours of 9:00 a.m. and 8:00 p.m. on Sunday or a Federal holiday. Noise generated outside of the hours specified are subject to the noise standards identified in Table 8.24.040; F. All mechanical devices, apparatus or equipment which are utilized for the protection or salvage of agricultural crops during periods of potential or actual frost damage or other adverse weather conditions; G. Noise sources associated with agricultural operations provided such operations take place between the hours of 7:00 a.m. and 8:00 p.m. on any day except Sunday or a Federal holiday, or between the hours of 9:00 a.m. and 8:00 p.m. on Sunday or a Federal holiday; E-27 Page 3

H. Noise sources associated with agricultural pest control through pesticide application, provided that the application is made in accordance with restricted material permits issued by or regulations enforced by the Agricultural Commissioner; I. Noise sources associated with the maintenance of real property, provided such activities take place between the hours of 7:00 a.m. and 8:00 p.m. on any day except Sunday or a Federal holiday, or between the hours of 9:00 a.m. and 8:00 p.m. on Sunday or a Federal holiday. Operation of leaf blowers are regulated under OMC Chapter 8.26; J. Industrial or commercial noise affecting residential units, when the residential unit is associated with said industrial or commercial use (e.g. caretaker's dwellings); K. Any maintenance or construction activity undertaken by a public agency or utility within street right of way; L. Mobile noise sources including but not limited to operational noise from trains, or automobiles or trucks traveling on roadways. Transportation noise as related to noise/land use compatibility is subject to the City's General Plan Noise Element; M. Any activity to the extent regulation thereof has been preempted by State or Federal Law. (Ord. No. 1-14, I, 8-12-14) 8.24.060 - Special Provisions for Schools, Hospitals and Churches. It is unlawful for any person to create any noise which causes the noise level at any school, hospital or church, while the same is in use, to exceed the noise limits as specified in Section 8.24.040, or which noise level unreasonably interferes with the use of such institutions. (Ord. No. 1-14, I, 8-12-14) 8.24.070 - Measurement of Noise Levels. The location selected for measuring exterior noise levels shall be the point closest to the noise source along the perimeter of the outdoor activity area (such as a private yard, patio, balcony, or common recreation area, as applicable pursuant to Section 8.24.040B. of this chapter) of the affected residential receiving property. If the location of the outdoor activity area is unknown or unclear, the noise standard shall be applied at the point closest to the noise source along the property line of the affected residential receiving property. (Ord. No. 1-14, I, 8-12-14) 8.24.080 - Enforcement Authority. A. The Chief Building Official or his/her designee are directed to enforce the provisions of this chapter. The Chief Building Official or his/her designee are authorized, pursuant to Penal Code Section 836.5, to arrest any person without a warrant when they have reasonable cause to believe that such person has committed a misdemeanor in their presence. B. No person shall interfere with, oppose or resist any authorized person charged with the enforcement of this chapter while such person is engaged in the performance of his duty. (Ord. No. 1-14, I, 8-12-14) 8.24.090 - Violation Public Nuisance. E-28 Page 4