Monthly Archives: January 2015

Noise: Adapting to a Pollution

A jumbo jet rumbles across the Seattle sky.  A garbage truck screeches to a halt outside.  And a neighbor slips on ear muffs, ignites a gassed up leaf blower and sends any unprotected eardrums into a fleeing panic.

In some instances, noise vibrations can cause the ear to bleed.  Exposure to loud rock music through blasting earbuds or concert hall speakers can lead to permanent hearing loss. Unmuffled motorcycles revving down residential streets can spike tempers and heart rates. Consistent screeches, pops and clack-clack-clacks from nearby construction projects can pump a person tight with stress.

Noise pollution is an unwanted or harmful sound from man-made things like automobiles, airplanes and industrial workplaces, expanding to sirens and horns, boats, trains, and lawn care machines.  Finding acoustic reprieve can be difficult.

Annoyance from noise is not just the reaction of an overly-sensitive person, but a symptom of an unhealthy environment.  In urban areas, daily immersion in waves of unwanted sound diminishes health, sleep and lifestyle quality.  The effects of noise on the human body range from hearing loss to heart disease and spikes in heart rate and blood pressure, to instigating the sympathetic nervous system (fight or flight) which can lead to sleeping disorders, stress and hypertension.

“People in noisy environments experience a subjective habituation to noise, but their cardiovascular system does not habituate…”, claims a February 2014 article published in Environmental Health Perspectives.  So, while we think we are getting used to the ever present urban sounds, the rationalization may just be in our minds and not translated to our organs and health needs.

When the blood begins to bubble, can we turn off the noise, control it in some way or leave the polluted space?  And if escape is not an option?  Maybe we’ll just adapt.

In urban habitats, animals have developed strategies to adapt to increasing noise pollution.  Research studies released in the past few years indicate that birds, for example, sing louder and at a higher pitch to separate their song from the low frequency traffic hum.  Besides loud-talkers yelling at cell phones and pedestrian voices raised to clear the thick haze of downtown traffic, human city dwellers have adapted in additional ways to compete with escalated sound levels.

Noise canceling headphones have become a popular fashion.  White noise generators mask the cacophony outside and provide a constant sound of wind, rain, or ocean waves for focusing, relaxing or sleeping.  Apps assist urbanites in the search for quiet spaces in cities.  Installing sound-dampening fiberglass insulation, double or triple pane windows and thick carpeting throughout a house increases acoustic comfort.  Even biologically, the human brain filters unwanted noise to focus on a desired sound.  In this process of auditory cognition, more immediate sounds take priority and others fade unnoticed, or are masked until consciously heard.

Over 40 years ago, the Environmental Protection Agency (EPA) recognized the impact of noise levels and in response, established a national policy under the Noise Control Act of 1972 to “…promote an environment for all Americans free from noise that jeopardizes their health and welfare.”  The EPA no longer directly monitors and manages noise pollution.  Since the early 1980‘s, individual states and cities have shouldered the responsibility.

State and local laws have adapted to address the swell of excessive noise.  In Washington State, the Department of Ecology asserts that “Any loud noise that occurs between 10:00 p.m. and 7:00 a.m. could be considered noise pollution…The zoning of your location also determines if a noise is considered “pollution”.”   Noise Abatement Coordinators in the city of Seattle hear questions regarding the Noise Code that addresses sound levels for commercial and construction projects, while Police Officers enforce the Municipal Code sections that cover noise disturbances ranging from barking dogs and human voices to motors and music.

The state has attempted to control the effects of a chronic noise sprawl, but in at least one instance, the sound waves would not be stopped.  In 2010, contractor crews for the Washington State Department of Transportation finished installing 700 noise-absorbing ceiling panels above the express lanes on Interstate 5’s Ship Canal Bridge.  The project started in reaction to the escalated traffic noise vibrating from the interstate throughout the Seattle neighborhoods below.  After monitoring the project results for a couple of years, officials determined that the finished construction did not significantly impact the noise levels from the stretch of road.  In part, the adaptations could not control all of the noise diffractions and reflections.

Daily exposure to the chronic jumble of noise is part of the Seattle city scene.  Bus routes have been cut due to budget issues potentially creating more traffic on the roads, and drones (unmanned aircraft) are said to be loud and on the horizon for package deliveries and potentially for law enforcement use.  While quieter hybrid and electric cars are commonly seen on the roads, legislation in the United States requires them to emit warning sounds for the safety of pedestrians.  Maybe urban noise pollution has reached a threshold where less noisy things are too ‘quiet’ and have become a potential threat.

An article in the August 2013 issue of Men’s Health Magazine stated that out of 100 U.S. cities, with number 1 (Durham, North Carolina), as the quietest and 100 (Houston, Texas) as the loudest, Seattle ranked number 26.  But since Seattle’s population grew by 2.8 percent (almost 18,000 residents) in 2013, becoming the nation’s 21st biggest city, should a noise swell be expected?  And what adaptations will be made?

There are always earplugs.  Until they aren’t enough.

© M.R.Collier, A Way of Your Own, 2015