(SAN DIEGO) The human body is remarkably good at getting used to the environment around it. You’ve probably experienced this if you’ve ever gone to a matinee and emerged from the dark theater into sunshine. Your eyes sting, so you squint and shield your face until they adjust to the bright sunlight.
In the same way, the body can grow accustomed to constant noise. With repeated exposure to traffic, leaf blowers, construction, loud music, crowded restaurants, fitness classes and sporting events, you can become accustomed to loud environments. Over time, what once seemed unusually loud may barely register.
But what feels normal isn’t necessarily safe. Noise is an important but often overlooked environmental health hazard, with effects ranging from hearing loss to cardiovascular disease.
I think about noise constantly because I’m an audiologist and hearing scientist with expertise in occupational exposures. But hazardous noise isn’t limited to the workplace. You likely encounter noise every day without knowing when it poses a risk. The good news is that many of the harmful effects of noise are preventable – once you know what to listen for.
Noise affects more than your ears
The most obvious consequence of excessive noise is hearing damage. Loud sounds can damage delicate sensory cells in the inner ear, leading to permanent hearing loss. Tinnitus, or ringing in the ears, is another common consequence of noise exposure.
But hearing damage is only part of the story. Chronic environmental noise can affect health through other pathways, too. Noise acts as a stressor, activating the autonomic nervous and endocrine systems and affecting heart rate, blood pressure and other physiological processes. It can also disturb sleep, triggering stress responses even without fully waking us.
Over months or years, these repeated effects can take a toll on the body. Long-term traffic noise exposure has been linked to hypertension, coronary artery disease, stroke and Type 2 diabetes.
Workplace noise recommendations are primarily designed to protect workers from hearing loss. In contrast, the World Health Organization’s environmental noise guidelines recommend lower levels because they consider longer exposure periods and broader effects on health.
How loud is too loud?
The risk from noise depends on how loud it is, how long you’re exposed and how close you are to the source. Extremely loud sounds, such as fireworks or gunshots, can damage hearing almost instantly, especially at close range. Other sounds, such as power tools, loud music or heavy traffic, can pose a risk more gradually, as exposure adds up over time.
The National Institute for Occupational Safety and Health recommends limiting occupational noise exposure to 85 A-weighted decibels, or dBA, averaged over an eight-hour workday. A-weighting adjusts the measurement to better reflect how the human ear responds to sound. For every 3 dBA increase, the recommended exposure time is cut in half.
Similar benchmarks are used elsewhere: Australia limits workplace exposure to 85 dBA over 8 hours, while the European Union and Great Britain require protective measures beginning at 80 dBA and additional measures at 85 dBA, and both prohibit exposure above 87 dBA after accounting for hearing protection. Though regulatory details differ, 85 dBA averaged over eight hours is a widely used international benchmark for occupational noise.
And you don’t get a fresh start each time you leave a noisy environment. Rather, noise exposure adds up over the course of a day. Spending four hours at 88 dBA uses the same maximum recommended daily noise dose as eight hours at 85 dBA. Time spent around loud traffic, using power tools, attending a sporting event or listening to loud music can all contribute to that daily dose.
How to protect yourself from too much noise
Protecting your hearing doesn’t necessarily mean avoiding sound altogether. The goal is to manage your daily noise dose.
It helps to start by learning your baseline daily exposure. The National Institute for Occupational Safety and Health offers a free app called the NIOSH sound level meter that can estimate the noise level around you.
When you have a choice, select quieter equipment and environments. When driving, keep your car windows closed in heavy traffic. When you go out to eat, try to choose a table away from noise sources in a loud restaurant.
But if you find yourself in a noisy environment, it’s helpful to take breaks and wear hearing protection whenever possible. Filtered earplugs reduce sound levels while still allowing you to enjoy music or participate in conversation.
Whenever possible, it’s a good idea to turn down the volume on your headphones. Most smartphones allow you to set an upper limit on audio volume so that you aren’t turning up the volume on your music or podcast to unsafe levels. As the ambient sound increases, noise-canceling headphones can help keep the volume at a safe level.
Increasing your distance from the noise source can also make a significant difference. At concerts and sporting events, move away from speakers. If you’re at a loud event for several hours, step outside or find a quieter area periodically to give your ears a break. When using power tools, lawn equipment or other machinery, wear properly fitted earplugs or earmuffs from the start, rather than waiting until the noise becomes uncomfortable.
To help create a quieter environment at home, consider battery-powered lawn tools, which are often quieter – and produce fewer emissions – than gas-powered models. When purchasing household appliances such as dishwashers, compare their noise ratings and choose quieter models when possible.
Noise exposure is a public health problem
Individual behaviors are important, but noise pollution won’t be solved one pair of earplugs at a time. Most people cannot control the noise they are exposed to. A farmer cannot turn down the noise on a tractor. A child cannot reroute the highway outside their bedroom. A restaurant employee may spend an entire shift around a live band and rowdy patrons, without the option to retreat to a quieter environment.
Although each of us can take steps to reduce the noise around us, individual actions only go so far without broader changes. Protecting public health also requires manufacturers to buy or design quieter equipment, architects and builders to consider acoustics in the design of buildings, city planners to reduce transportation noise and create quieter public spaces, and employers to implement workplace controls to reduce noise at its source.
This article is republished from The Conversation, a nonprofit, independent news organization bringing you facts and trustworthy analysis to help you make sense of our complex world. It was written by: Laura Coco, San Diego State University
Read more:
- Urban noise pollution is worst in poor and minority neighborhoods and segregated cities
- What can cities do to correct racism and help all communities live longer? It starts with city planning
- After a delay, New York City is moving ahead with congestion pricing to improve traffic, air quality and public transit
Laura Coco receives research funding from the National Institutes of Health (NIH). The views expressed in this article are those of the author and do not necessarily reflect the official views of the NIH.
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