Peoria, IL Noise Ordinances: Vehicle Noise (2026)

Sec. 15-68's decibel table uses A-weighted sound level meters meeting the Z24.3-1944 standard (now ANSI S1.4 successor), measured from the right rear wheel of the vehicle in motion as it passes the meter. The graduated chart (95.5 dBA at 15 ft / 93 dBA at 20 ft / 91 dBA at 25 ft / 89.5 dBA at 30 ft / 88 dBA at 35 ft / 87 dBA at 40 ft / 86 dBA at 45 ft / 85 dBA at 50 ft) provides a sound-pressure curve consistent with hemispheric propagation; an officer with a calibrated meter measures at any of these distances and a reading above the chart value is prima facie evidence of excessive or unusual noise. Sec. 15-67 separately prohibits the discharge of any steam-engine, stationary internal-combustion-engine, motorboat, or motor vehicle exhaust 'into the open air' except through a muffler that effectively prevents loud or explosive noise — covering modified exhaust, cutouts, and bypass systems. Sec. 15-66 covers air horns, train horns, exhaust whistles, and unnecessary horn use in traffic. Sec. 15-75 (mobile sound amplification) and Sec. 15-77 (vehicle seizure with $250/$500 escalating penalty plus towing/storage) handle stereo and PA systems on the public way. The Illinois Vehicle Code 625 ILCS 5/12-602 sets the statewide minimum muffler requirement; Peoria as a home rule city imposes the stricter decibel chart.