Acute acoustic trauma (AAT) is a serious ear injury that can occur in less than a second, but its effects can last a lifetime. This condition is caused by a sudden and extremely loud noise, such as an explosion. Unlike noise-induced hearing loss, which typically develops gradually over time, acute acoustic trauma happens instantly.
In this guide, we provide a complete overview of acute acoustic trauma, including common symptoms, causes, and treatments.
Jump Ahead:
What Is Acute Acoustic Trauma? (AAT)
Acute acoustic trauma (AAT) is an injury to the inner ear that results in sudden hearing loss that is often permanent. It occurs when the delicate structures of the inner ear are injured by an intense sound event typically exceeding 140 decibels (dB) and lasting for less than 0.2 seconds.1
When sound waves enter the ear, the tiny hair cells in the cochlea convert them into electrical signals that the brain translates into sound. An extremely loud blast of noise—such as an explosion or a gunshot at close range—can instantly damage or destroy these delicate cells.
Because these auditory structures do not regenerate, this damage often results in permanent hearing loss.
Acute Acoustic Trauma Symptoms
The signs of acute acoustic trauma usually appear immediately or shortly after exposure to an intense sound. They can vary depending on the intensity of the noise and the extent of inner ear damage, but common symptoms include:
- Ear pain
- Sound sensitivity
- Dizziness or vertigo
- Sudden hearing loss in one or both ears
- Feeling of fullness or pressure in the ear
- Ringing, buzzing, or hissing in the ear (tinnitus)
These symptoms can last a short time or become permanent, depending on the severity of the damage. If you experience sudden changes in hearing, it’s important to seek medical care as soon as possible. Prompt evaluation by a specialist can help determine the extent of the injury and guide treatment.
Acute Acoustic Trauma vs. Noise-Induced Hearing Loss
While both acute acoustic trauma (AAT) and noise-induced hearing loss (NIHL) involve damage to the inner ear from loud sounds, the way they occur and progress is very different.
Onset:
- AAT happens suddenly, often after a single loud event such as an explosion.
- NIHL develops gradually from repeated exposure to loud sounds, like years of working with noisy machinery or in loud environments.
Symptoms:
- AAT usually causes an immediate change in hearing and/or feeling of pain or pressure.
- NIHL starts subtly and gradually becomes more severe over time, often going unnoticed for years.
Understanding the difference between these two conditions is important because it shapes both treatment and prevention strategies. AAT often requires urgent medical attention, while NIHL highlights the importance of lifelong hearing health care.
Acute Acoustic Trauma Causes
Acute acoustic trauma is caused by exposure to sudden, high-intensity noise, typically 140 decibels (dB) and louder.1 For reference, 140 dB is roughly as loud as a jet engine during takeoff.
While some causes are linked to occupational risks, others occur in everyday situations. Understanding the most common triggers can help you take steps to protect your hearing.
Below are some of the most common causes of acute acoustic trauma:
Explosions and Blasts
Explosions are one of the most common and severe causes of acute acoustic trauma. Blast waves from explosives generate intense sound pressure that can instantly damage the inner ear. This sudden force can rupture the eardrum, damage the tiny ossicular bones in the middle ear, and/or destroy the inner ear hair cells responsible for hearing.
People most at risk include military service members, first responders, and demolition or mining workers. Research shows that deployed military personnel are at a 49% higher risk of hearing loss due to blast events.2 Over 60% of wounded-in-action service members have hearing loss or eardrum injuries due to AAT.3
Gunfire
Gunfire, especially at close range and without hearing protection, is another leading cause of acute acoustic trauma. Depending on the firearm, gunshot sound levels can range from 140 dB to 190+ dB. This means military personnel, law enforcement officers, and hunters are at particular risk of AAT.
Studies show that people who use firearms frequently are at a much higher risk of hearing damage. An estimated 37.1% of firearms users have high-frequency hearing loss, while 17.3% have speech-frequency hearing loss.4
Industrial or Construction Accidents
Worksites such as factories, shipyards, and construction zones often involve heavy machinery, power tools, and other sources of high noise levels. While long-term exposure to these environments can cause gradual noise-induced hearing loss, acute acoustic trauma is also possible.
Common causes include the explosive release of compressed air, a sudden machinery malfunction, large metal-on-metal impacts, and more. Workers caught off guard are especially vulnerable if they are not wearing hearing protection at the time.
Airbag Deployment
Airbags are designed to save lives in the event of a car crash, but their rapid deployment can create an intense acoustic event. When an airbag inflates, it releases a burst of gas and pressure in a fraction of a second. This can result in potentially harmful noise levels, loud enough to cause acute acoustic trauma.
Because this occurs inside the enclosed space of a vehicle, the sound is amplified and can cause immediate inner ear damage. In some cases, eardrum injuries and permanent hearing loss have been documented following collisions with airbag deployment. Even the crash itself can reach an estimated 145 dB on average, which can result in lasting hearing damage.5
Sudden Pressure Changes
In some situations, acute acoustic trauma is not caused by noise alone but by a combination of loud sound and rapid pressure changes. Events such as diving accidents, explosions, or blasts in confined spaces (like tunnels or mines) can create sudden shifts in air or water pressure that place extra stress on the ear.
These abrupt changes can rupture the eardrum, damage the tiny ossicular bones in the middle ear, or cause inner ear damage. People who work in diving, aviation, tunneling, or military environments face a higher risk of this type of injury.
Acute Acoustic Trauma Treatments
Treatment for acute acoustic trauma focuses on restoring as much hearing as possible, managing symptoms, and preventing further injury. The specific approach depends on the severity of hearing loss and how soon the individual receives care.
Treatment options for acute acoustic trauma can include:
- Hearing Aids: For individuals with permanent hearing loss, prescription hearing aids can help restore functional hearing and improve quality of life.
- Tinnitus Management: Persistent ringing or buzzing in the ears (tinnitus) can be addressed with sound therapy or specialized hearing devices to make daily life more comfortable.
- Hearing Protection: Hearing protection devices (HPDs) like earplugs and earmuffs reduce the risk of further damage.
If you experience acute acoustic trauma, prompt evaluation and care are critical. While hearing damage is often permanent, early intervention can help reduce the severity of symptoms and improve recovery.
Acute Acoustic Trauma Prevention
While treatments exist, the best strategy is to prevent acute acoustic trauma from occurring in the first place. Using hearing protection in high-risk environments, limiting exposure to loud noises, and following safety protocols are all critical steps in preserving long-term hearing health.
Safeguard Your Hearing Health with Audibel
Acute acoustic trauma (AAT) happens in a fraction of a second, but the effects can last a lifetime. By understanding the causes, prioritizing hearing protection, and attending routine hearing exams, it is possible to minimize risks and protect your hearing health long-term.
Don’t wait until the damage is already done. The hearing care specialists at Audible are here to help you safeguard your hearing health. Find a clinic near you today.
References
- Ghazaryan, V., Sutton, A. E., & De Jong, R. (2024, November 13). Acute acoustic trauma. StatPearls – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK609092/
- Joseph, A. R., Shaw, J. L., Clouser, M. C., MacGregor, A. J., & Galarneau, M. R. (n.d.). Impact of Blast Injury on Hearing in a Screened Male Military Population. American Journal of Epidemiology, 187(1), 7–15. https://doi.org/10.1093/aje/kwx199
- Cho, S., Gao, S. S., Xia, A., Wang, R., Salles, F. T., Raphael, P. D., Abaya, H., Wachtel, J., Baek, J., Jacobs, D., Rasband, M. N., & Oghalai, J. S. (2013). Mechanisms of Hearing Loss after Blast Injury to the Ear. PLoS ONE, 8(7), e67618. https://doi.org/10.1371/journal.pone.0067618
- Finan, D., Flamme, G., Murphy, W., Stewart, M., Lankford, J., Tasko, S., & Meinke, D. (2017). Prevention of Noise-Induced Hearing Loss from Recreational Firearms. Seminars in Hearing, 38(04), 267–281. https://doi.org/10.1055/s-0037-1606323
- Banglmaier, R. F., & Rouhana, S. W. (n.d.). Investigation into the noise associated with airbag deployment: part III – sound pressure level and auditory risk as a function of inflatable device. PubMed, 47, 25–50. https://pmc.ncbi.nlm.nih.gov/articles/PMC3217582/
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