Ontario Municipal Code Art. 1 General

(a) “CNEL” means community noise equivalent level.

(b) “dB” means decibel.

(c) “dB(A)” means (A) weighted decibel.

(d) “STC” means sound transmission class.

(e) “Group R” means any residential land use, plus any other use generally considered incompatible with airport operations, such as churches, schools and hospitals.

(§ 2, Ord. 2616, eff. June 20, 1996)

(a) The purpose of these sections is to safeguard life, health, property and public welfare by establishing minimum requirements regulating the design, construction and modification of buildings in the vicinity of Ontario International Airport. These sections are not intended to abridge any safety or health requirements required under any other applicable codes or ordinances.

(b) These sections define the procedures for implementing the sound insulation requirements set forth in the State Division of Aeronautics Noise Standards (California Code of Regulations, Title 21, Subchapter 6) and the State Building Code (California Code of Regulations, Title 24, § 3501). Based on these documents, acoustic insulation shall be provided within specified community noise equivalent level (CNEL) contours to ensure an interior CNEL (due to exterior noise) of forty-five (45) dB or less in all habitable rooms in both single and multifamily residential dwellings and in specified noise-sensitive nonresidential buildings.

(§ 2, Ord. 2616, eff. June 20, 1996)

The provisions of this chapter shall apply to all Group R buildings (single and multifamily residential dwellings), as defined by the Uniform Building Code, within the most recent fourth quarter sixty (60) CNEL noise contour map of Ontario International Airport published by the City of Los Angeles Department of Airports and to specified nonresidential buildings within the sixty-five (65) CNEL of the airport. Group R buildings are not allowed to be constructed in the seventy-five (75) CNEL or greater noise contour on the latest annual map. This chapter is intended to supplement the provisions of the Uniform Building Code and in the case of conflict between this chapter and any other applicable codes, the more restrictive requirements shall be met.

(§ 2, Ord. 2616, eff. June 20, 1996)

(a) Prescriptive design/construction standards are provided for the sound insulation of new construction or modification of Group R buildings located within the most recent fourth quarter sixty-five (65) annual CNEL contour. Within the most recent fourth quarter sixty (60) CNEL to the sixty-five (65) CNEL zone, Group R buildings that are proposed for construction or modification are not required to comply with the prescriptive sound insulation standards; however, a certified acoustical engineer must provide certification that planned building modification and construction will achieve at least the forty-five (45) CNEL standard for all habitable rooms.

(b) Prescriptive design/construction standards are not provided for noise-sensitive nonresidential buildings (schools, churches and hospitals) that constitute incompatible land use within the sixty-five (65) CNEL contour; however, a certified acoustical engineer must provide certification that the planned construction or modifications will achieve the required noise environment.

(c) Deviations from the specified building requirements (i.e., standards, materials and construction assemblies) provided in the building requirements herein are permissible only if all deviations are certified to comply with and achieve the forty-five (45) CNEL standard for every habitable room constructed or modified. All deviations require approval by the Building Official and certification by a certified acoustical engineer. Acoustic measurements will be conducted by a certified acoustical engineer to verify that the forty-five (45) CNEL standard is not exceeded for all habitable rooms incorporating deviations from the building requirements.

(d) All new and modified residential construction within the sixty-five (65) CNEL contour is subject to post-construction/pre-occupancy acoustic measurement at the discretion of the Building Official. Occupation of all habitable rooms not achieving the required CNEL rating may be precluded until such time as acoustic modification of that room achieves at least the forty-five (45) CNEL standard.

(§ 2, Ord. 2616, eff. June 20, 1996)

Addition or alteration of floor area may be made to existing Group R buildings within the sixty (60) CNEL noise contour but outside the seventy-five (75) CNEL contour without making the entire building comply with all the requirements of this chapter for new construction unless the cost of improvements is seventy-five (75) percent or more of the total assessed value of the structure, in which case the entire building shall be made to comply. No addition of habitable space shall be made to existing Group R buildings inside the seventy-five (75) CNEL contour unless the entire building is made to comply. All additions of separable habitable rooms, and all separable habitable rooms or areas that result from an expansion of the building, including both the newly expanded area and the pre-existing room or area, shall fully comply with the design and construction procedures and standards set forth in this Code.

(§ 2, Ord. 2616, eff. June 20, 1996)

(a) Nonresidential noise-sensitive buildings within the most recent fourth quarter sixty-five (65) CNEL contour that are incompatible land uses under the State Noise Standards and described as schools, hospitals, and convalescent homes, churches, synagogues, temples, and other places of worship, and are proposed to be constructed or modified, shall be designed to provide an interior CNEL due to aircraft noise of forty-five (45) dB or less.

(b) Additions to the buildings described in subsection (a) of this section shall comply with the requirements of § 8-15.105.

(§ 2, Ord. 2616, eff. June 20, 1996)