In the US, local and state noise ordinances have been protecting citizens against sound and vibration disturbances for over 70 years. An ideal noise ordinance would be easy to understand and easy to enforce, but due to the technical jargon contained in these documents and the equipment needed to accurately measure sound levels, this is often not the case. Read on to learn more about the ins and outs of our favorite group of laws.
For a vast stretch of human history, human generated noise wasn’t very problematic; prior to the Industrial Revolution, the loudest sounds were aperiodic and of short duration. Advances in technology like the steam engine and electricity and the push for faster, stronger, and bigger machines – and the proliferation of those machines – created environments that were objectionably loud and sometimes dangerous. After years of movements to reduce the cacophony of the post-industrial world, Chicago enacted the first quantitative noise ordinance in 1950.
Noise ordinances typically fall under one or more of three categories: qualitative, referential, and absolute. A qualitative noise ordinance, on the surface, seems simple: if a sound is deemed objectionable by a “reasonable” person or is “audible” at some given distance, that sound is not in compliance. How then do we define reasonable? Audible? At best, ordinances in this category include definitions of these vague terms although many do not. In these cases, we must come up with clever ways to assign quantitative criteria to these subjective terms.
Well-crafted noise ordinances include quantitative criteria, which can be referential, absolute, or both. A referential noise ordinance, such as the City of Philadelphia’s, sets the upper limit of compliance based on a measured background sound level in the area of interest. An absolute noise ordinance, like the one the State of New Jersey enforces, simply sets a decibel limit, and if sound generated by a source of interest exceeds that limit, that sound source violates the noise ordinance. Other municipalities, including New York City, combine both types: hard upper limits apply where background sound levels are sufficiently low, but once the background sound level exceeds those upper limits, a referential aspect comes into play.
Quantitative ordinances also differ in the metrics they require; A-weighted decibels (dBA) are a common single-number rating that can be measured with a low cost device or app, but sounds that nominally comply with a dBA limit can have vastly different tonal characteristics. Sound level limits defined in octave bands help to reduce the likelihood of annoying tonal sounds or sources of low-frequency sound slipping through the net, but require more advanced equipment that is more expensive and more difficult to use properly (hint: we have it and know how to use it!).
While each municipality or state has their own definition of what sounds are permissible, rest assured that we can guide you through what is “reasonable”, audible, or – hopefully – quantifiable. Whether the issue is a noisy bar across the street or determining whether your new generator will make the cut, you know you can always turn to your local noise ordinance…and us!