What is noise-induced hearing loss?
Every day, we experience sound in our environment. Normally, these sounds are at safe levels that don’t damage our hearing. But sounds can be harmful when they are too loud, even for a brief time period, or when they are both loud and long-lasting. These sounds can damage sensitive structures in the inner ear and cause noise-induced hearing loss (NIHL).
Noise-induced hearing loss (NIHL) can be immediate or it can take a long time to be noticeable. It can cause temporary or permanent hearing loss, and it can affect one ear or both ears. The good news is that noise-induced hearing loss is 100% preventable.
What causes NIHL?
Recreational activities that can put you at risk for NIHL include target shooting and hunting, motorcycle riding, listening to MP3 players at a high volume through insert earphones or headphones, playing in a band, and attending loud concerts. Harmful noises at home may come from sources including lawnmowers, leaf blowers, and power tools. Sound is measured in units called decibels. Sounds of less than 75 decibels, even after long exposure, are unlikely to cause hearing loss. However, long and repeated exposure to sounds at or above 85 decibels can cause permanent hearing loss. The louder the sound, the shorter the amount of time it takes to cause noise-induced hearing loss.
What are the effects and signs of NIHL?
When you are exposed to noise at or above 85dB for 8 hours or more, you may be at risk to slowly start to lose your hearing. Due to the fact that damage from noise exposure is usually gradual, you might not notice a difference, or you might ignore the signs of hearing loss until they become more pronounced. Over time, sounds may become distorted or muffled, and you might find it difficult to understand other people when they talk or have to turn up the volume on the television. The damage from NIHL, combined with aging, can lead to a hearing loss that will need to be treated with hearing aids to amplify speech and the sounds around you. Hearing aids will help you hear, communicate, and participate more fully in daily activities, but it will never restore your hearing.
NIHL can also be caused by extremely loud bursts of sound, such as gunshots or explosions, which can rupture the eardrum or damage the bones in the middle ear. This kind of NIHL can be immediate and permanent.
Loud noise exposure can also cause tinnitus—a ringing, buzzing, or roaring in the ears. Tinnitus may subside over time, but can sometimes continue constantly or occasionally throughout a person’s life. Hearing loss and tinnitus can occur in one or both ears. Sometimes exposure to impulse or continuous loud noise causes a temporary hearing loss that disappears 16 to 48 hours later.