Vanderburgh County, IN Noise Ordinances: Vehicle Noise (2026)

40, Vehicle Noise Restrictions, applies to any "motor vehicle," a term the code defines to include automobiles, motorcycles, mopeds, trucks, and recreational vehicles, operating on a "public way," defined by example to include streets, alleys, and sidewalks. 010(B) sets the operative limit: no person may allow a motor vehicle on a public way to emit a sound pressure level above 85 dbA measured at 50 feet, regardless of what part of the vehicle produces the sound, whether engine, exhaust, tires, or stereo. The code carves out one exception: a vehicle accelerating from a full stop may emit up to 90 dbA measured at the same 50-foot distance, recognizing that acceleration naturally produces more noise than steady cruising.

Subsection (C) addresses modified exhaust systems directly, permitting owners to modify an exhaust system only if the modified system still includes baffles or other noise-suppressing devices; a straight-piped or baffle-free exhaust that exceeds the dbA limits is not shielded by the fact that it was a deliberate modification. Because the definitions and limit apply county-wide to any public way, the rule reaches both county highways and, through the joint city-county traffic framework referenced elsewhere in Title 10, streets that fall under shared jurisdiction. The chapter does not create a decibel table by time of day or a separate stereo-specific rule; the 85/90 dbA thresholds are the sole numeric standard, applied uniformly regardless of the sound's source.