A. Any noise measurement made pursuant to the provisions of this chapter shall be made with a sound level meter using the “A” weighted network (scale) at slow meter response. Fast meter response shall be used for impulsive type sounds. Calibration of the measurement equipment utilizing an acoustical calibrator certified by its manufacturer to be in compliance with National Bureau of Standards (NBS) reference calibration levels shall be performed immediately prior to recording noise level data.
B. Exterior noise levels shall be measured within fifty (50) feet of the affected residence, school, hospital, church or public library. Where practical, the microphone shall be positioned three to five feet above the ground and away from reflective surfaces.
C. Interior noise levels shall be measured within the affected dwelling unit, at points at least four feet from the wall, ceiling or floor nearest the noise source, with windows in the normal seasonal configuration. Reported interior noise levels shall be determined by taking the arithmetic average of the readings taken at the various microphone locations. (Prior code § 5090.3)