Hearing loss caused by loud noises is called noise-induced hearing loss (acoustic trauma). It is more common for gradual hearing loss to occur from long-term (chronic) exposure to loud noise than from a sudden (acute) loud burst of sound. Hearing loss may be temporary or permanent. Long-term exposure to loud noises can cause permanent hearing loss.

Common causes of acoustic trauma include:

• Loud music, such as live musical performances and home, auto, or portable stereo systems. Hearing loss is usually temporary but can be permanent.
• Industrial sounds, such as traffic, sirens, jet engines, power tools, chain saws, jackhammers, or hydraulic machinery.
• Physical injury to the ear. Severe injury can rupture the eardrum. Physical injury can be caused by:
  • A blow to the side of the head.
  • An explosive burst of sound close to the ear, such as when an air bag is set off during a motor vehicle accident.
  • Rapid changes in environmental pressure, such as from underwater diving or descending in an airplane.

Most people stop hearing high-frequency sounds, such as bells and chimes, first. Later, it becomes harder to hear lower-frequency sounds, such as voices.