Did you know that you could develop hearing loss simply from the noises you are exposed to on a daily basis? The world is a really loud place. In order for us to protect ourselves from noise induced hearing loss, we need to know what these sounds are, and how long we can listen to them without damaging our hearing.
What is Noise Induced Hearing Loss?
Noise induced hearing loss is a completely preventable type of hearing loss that – once developed – is permanent and irreversible. One can develop noise induced hearing loss from a one-time exposure to an extremely loud noise (i.e. being very near to an airplane takeoff without hearing protection). More often, however, noise induced hearing loss occurs due to exposure to noises over a longer period of time, usually hours at a time, for years or decades. It is important to know the risks for noise induced hearing loss and whether you are exposed to them. Because hearing loss typically develops over a period of time, it is never too late to start protecting your hearing.
Noise Exposure in the Workplace
The National Institute for Occupational Safety and Health (NIOSH), created limits for noise exposure on-the-job in 1998. These recommended exposure limits or RELs are based on the best available research and science and are measured using globally recognized sound measurements called decibels or dBA. NIOSH set the workplace REL to 85 dBA for an eight-hour workday, five days a week, over the span of a person’s career. 85 dBA is about as loud as a noisy urban area during the day or a garbage disposal when standing three feet away (http://www.dot.ca.gov/dist2/projects/sixer/loud.pdf).
While 85 dBA is the recommended limit, louder noises at work are often unavoidable. Each time a noise increases by 3 dBA, the allowable exposure time is cut in half.
Hours to Meet Maximum Daily Dose at 100%
85 dBA – 8 hours
88 dBA – 4 hours
91 dBA – 2 hours
94 dBA – 1 hour
97 dBA – 30 minutes
100 dBA – 15 minutes
For a person working at 85 dBA for eight hours, five days a week – he or she will reach 100% of their daily sound limit. This model does not allow for any noise exposure outside of the workplace, such as attending a concert or riding a motorcycle. It is recommended that those who are exposed to sounds this loud at work should wear hearing protection.
Noise Exposure in the Environment
We understand that noises certainly do not stay at work. Noisy environments are everywhere: at restaurants, in traffic, at music/sporting venues, in the theatre and even in schools. NIOSH specified that the aforementioned noise limits were strictly for the workplace, and should not be used as a rule for the general public. In 1974, the US Environmental Protection Agency (EPA) did issue a report that recommended an exposure limit of 70 dBA over the course of a 24-hour period or 75 dBA over the course of an 8-hour period, however, they were also clear that these guidelines should not be used as a regulation.
The difference between the occupational guidelines and these general guidelines is that the general guidelines aim to protect against annoying noises as well as dangerous ones. The general guidelines also account for 365 days of exposure versus the 250 days a typical American works per year.
Clear as mud, right?
We understand this can all seem very confusing and overwhelming – and it can be hard to determine whether or not you are protecting your hearing. As a general rule, if you are having difficulty having a conversation with someone three feet away from you, you are in a noisy environment and should either reduce exposure or wear hearing protection. It is also possible to download an app for your phone that helps to measure noises around you, and alert you if you are approaching 100% of your daily exposure (https://blogs.cdc.gov/niosh-science-blog/2014/04/09/sound-apps/).
Get Your Hearing Assessed
If you are worried about your exposure to noise or think you might already be experiencing some of the signs of noise induced hearing loss, it is important to reach out to us at Hearing Health as soon as possible to schedule a comprehensive hearing exam. This quick and painless exam will look at your unique hearing profile, and will be able to determine which treatment path is the best fit for you. Reach out to us today. Our friendly team is looking forward to hearing from you.