Why some noise ordinances aren’t enough
Do you know what’s in your city’s noise ordinance? Does it get enforced? When was it last updated? A typical local noise ordinance might cover the hours of day/night, traffic noise, mechanical equipment, outdoor amplifiers, and barking dogs. Some might specify a measurement (in decibels) for maximum daytime and nighttime noise levels. But how comprehensive are noise ordinances?
Plainly audible versus decibels and frequency
In some cases, noise ordinances don’t specify enough clear guidelines on today’s impactful noise issues. These can include: leaf blowers, modified (amplified) exhaust systems on vehicles, subwoofers in multi-unit dwellings, data centers, pickleball courts, and more. And many noise ordinances don’t yet account for low-frequency noise, which can be extremely disruptive to human health. Some cite decibel readings, but not low frequency (in Hertz). Typically, low frequency is under 150 Hz.
On the Soundproofist YouTube channel, we show an example of how loudness and frequency are different, yet both are important. A low-frequency noise doesn’t need to be loud (in decibels) to cause annoyance or disruption. Low-frequency noise comes from HVAC, trucks and motorcycles, gas-powered leaf blowers, data centers, and subwoofers. For comparison, pickleball noise is typically mid-frequency noise, which might be picked up with dBA measurements. Low-frequency measurements require different measurement standards, such as dBC (versus dBA) or octave-band measurements, which display frequency bands across the spectrum in segments from low frequency to high.
Noise ordinances are typically regional. There isn’t a single nationwide or global noise ordinance, so most cities and counties create their own. Soundproofist collects and publishes a sampling of noise ordinances from around the world, and we looked at some of these ordinances to see how they cover modern noise concerns.
See the video (with decibel/frequency tests)
Some municipalities are actively keeping up
We discovered some U.S. municipalities that try to keep up with noise concerns and measurement standards. A good example is Chicago. Like some other cities, they cite dBA explicitly: 55 dBA/70 dBA, depending on the distance. However, for industrial/manufacturing areas, they also use octave-band decibel levels. This is genuine frequency-specific analysis, not just an A-weighted (dBA) number.
Denver cites explicit dBA limits (55 day/50 night residential). But they also began a revision process in 2024–2025, which could move them away from decibel measurements towards a “plainly audible” standard that’s enforced with time-stamped video. This is because Denver’s Department of Public Health and Environment found that decibel measurements alone were hard to enforce consistently in the field. But “plainly audible” could also go both ways, because it’s more subjective.
Cheyenne, Wyoming considered and rejected a fixed 80 dB noise maximum in 2025. After deliberation, they settled instead on “unreasonable noise,” as determined by a police officer.
Portland, Oregon is moving in the opposite direction in 2026. Instead of using a “plainly audible” (more subjective) guideline, which local officials felt targeted certain businesses and musicians, they’ll use a decibel measurement. In Title 18, they explicitly define “narrow band sound” and “octave band,” and they’re reducing the allowable limit by an additional 5 dBA, specifically to address narrow-band/steady (tonal, droning) sounds and also nighttime noise.
Seattle’s “Seattle Municipal Code Chapter 25.08 Noise Control” specifies a 5 dBA reduction. Under the code’s modifications, if a sound source contains what they call a “pure tone component,” the maximum (allowable) exterior sound-level limits get lowered by 5. The definition of a pure tone component is “a single-frequency sine wave that acts as a basic building block of a complex sound.”
Prince William County, Virginia updated its noise ordinance in May, 2026 to address low-frequency noise from data centers. Data facilities were creating a nuisance but didn’t exceed the noise ordinance’s stated dBA limits. Described now as “low tonal noise,” such as from HVAC and other mechanical equipment, this new addition includes C-weighting and octave bands. A step in the right direction!
Loudoun County, Virginia contains one of the largest concentrations of data centers in the world. And based on complaints, public officials realized that they need additional specifications in their ordinance. Their industrial noise limit is 55 dBA. And during the past few months, one data center received at least 12 noise complaints, even though it didn’t exceed the stated decibel limit. Clearly, using dBA measurements alone doesn’t address the noise issue. And their 26-year-old zoning regulations treat data centers like office space. Regional officials are still discussing this issue, and there’s a moratorium on approving new data centers until September 2026.
What Soundproofist found in many local noise ordinances
The following numbers don’t represent every noise ordinance in the world, or even in the USA. They come from a subset of global ordinances that Soundproofist links to from our site. Below is a quick review of standards for noise ordinances in 20 different US cities and counties.
Our classifications / definitions (divided into tiers):
- Tier 1 — Subjective: such as “unreasonably loud/excessive,” no number, no defined threshold
- Tier 2 — Single-weighted dBA: an explicit decibel number, A-weighted only
- Tier 3/3+ — Dual-weighted or better: dBA and dBC (or an equivalent composite like Leq/Lden), typically with an ANSI-spec meter requirement
- Mixed (split) — Subjective (Tier 1) for general noise, numeric (Tier 2) for one narrow case
The results for 20 U.S. cities:
Tier 1 (pure subjective):
2 cities (Memphis, Cheyenne)
Tier 2 (single-weighted dBA):
7 cities (Boston, Denver, Houston, Austin, Loudoun, NYC, Baltimore)
Tier 3 / 3+ (dual-weighted or better):
8 cities (Charlotte, Chicago, Pittsburgh, SF, Prince William, San Antonio, Portland, Seattle)
Mixed Tier:
3 cities (Louisville, Miami-Dade County, Nashville)
The takeaway
Local noise ordinances need to be reviewed periodically and updated, because today’s noise issues are different from 20 years ago. Subwoofers, extra-loud Bluetooth speakers, thunderous vehicles and delivery trucks, sightseeing helicopters overhead, data centers, and a lack of general awareness / empathy indicate that real noise-level guidelines need to be defined and enforced.
Learn more:
- Quiet Communities: “Quiet Communities wins landmark noise pollution ruling against the EPA”
- BBC: “A humming annoyance or jobs boom? Life next to 199 data centres” (on Loudoun County, VA)
- Cap City News: “Cheyenne council advances new vehicle noise ordinance after hearing from the public”
- Oregon State University: “Study documents unhealthy noise in Portland, provides research framework for other cities”