(a) Generally. Under this article, this method allows compliance with the aircraft noise reduction criteria specified in section 22-425 to be verified by actual sound level measurement.

(b) Noise level reduction requirements. All structures shall be designed and constructed so that the exterior shell of the structure (windows closed) provides measured noise level reduction equal to or greater than the minimum values listed in section 22-425. Noise attenuation for remodeling purposes need only be met pursuant to section 146-801(B).

(c) Testing. Sound level measurements shall be conducted in accordance with ASTM E 966 (current revision at time of plans submittal), "Field Measurement of Airborne Sound Insulation of Building Facades and Facade Elements,". The OITL shall be calculated using ASTM E 1332 (current revision at time of plans submittal), "Classification for Determination of Outdoor-Indoor Transmission Class".

The field test report shall be certified by an acoustical engineer, licensed as a professional engineer in the State of Colorado, whom is also a practicing acoustical engineer. (Ord. No. 2011-07, § 6, 4-11-2011)