Hearing Loss Prevention

Noise Exposure & Hearing Loss Prevention


Noise exposure is one of the most common, and most preventable, causes of hearing loss. Hearing loss due to noise exposure can be sudden if the sound is loud enough (e.g. a shotgun at close range), but more often it is gradual due to prolonged exposure to moderately loud noises (e.g. factory machinery).

Excessive noise exposure damages the hair cells in the cochlea, causing sensorineural hearing loss. Sensorineural hearing loss is usually permanent and cannot be treated medically or surgically. Once hair cells have been damaged, there is no way to replace or repair them. Damage to hair cells can also lead to tinnitus (ringing/buzzing in your ears).

Dangerous levels of noise can come from recreational activities such as noisy pubs/clubs, firecrackers, concerts, firearms, streaming loud music with earbuds or headphones, movie theatres, sporting events, woodworking, snowmobiles, motorcycles, and loud car stereos.

Certain occupations are at particular risk for noise-related hearing loss, including firefighters, construction workers, police officers, military personnel, factory workers, musicians, disc jockeys, and farmers. If you work in an at-risk occupation, check with your employer to ensure your hearing is protected according to national regulatory standards.

How Loud is Too Loud

A noise’s potential to damage hearing depends on the intensity of the sound (measured in decibels, dB) and the duration of the sound.

In general, the louder the sound in dB, the shorter the time you can be exposed to that sound before damage occurs. With every 5 dB increase in intensity, the amount of time you can be safely exposed to the sound is cut in half.

For example, a person without hearing protection can safely be exposed to an 85 dB sound for 8 hours, a 90 dB sound for 4 hours, a 95 dB sound for 2 hours, and so on. At 120 dB, the average sound intensity of a rock concert, a person can be safely exposed for only 7½ minutes.

A “safe” noise level is approximately 75 dB or less. According to The National Institute for Occupational Health and Safety (NIOSH), individuals can be exposed to sounds of 85 dB for no more than 8 hours. Individuals exposed to sounds above 85 dB should use appropriate, properly fitted hearing protection.

The graphs to the right indicate the noise levels of various activities, along with the amount of time before damage is likely to occur.

As a general rule, a noise is hazardous if you experience any of the following:

  • pain, ringing or buzzing in your ears after noise exposure
  • a feeling of fullness or pressure in your ears after you leave a noisy area
  • you have to shout over the noise to hear someone within an arm’s length away
  • other people’s speech sounds muffled or mumbled after noise exposure
  • 140 DECIBELS: Immediate danger to hearing (Gunshot, Jet engine at take-off)
  • 125 DECIBELS: Pain threshold (Air raid siren, Firecracker)
  • 120 DECIBELS: Risk of hearing damage in 7.5 min. (Rock concert, Sandblasting)
  • 115 DECIBELS: Risk of hearing damage in 15 min. (Baby's cry, Stadium sport game)
  • 110 DECIBELS: Risk of hearing damage in 30 min. (Snowmobile from driver's seat)
  • 105 DECIBELS: Risk of hearing damage in 1 hr. (Jackhammer, Helicopter)
  • 100 DECIBELS: Risk of hearing damage in 2 hrs. (Chainsaw, Stereo headphones)
  • 95 DECIBELS: Risk of hearing damage in 4 hrs. (Motorcycle, Power saw)
  • 90 DECIBELS: Risk of hearing damage in 8 hrs. (Lawn mower, Truck traffic)
  • 85 DECIBELS: Beginning of OSHA regulations
  • 30 DECIBELS: Faint sound, Whisper

Protect Yourself From Noise

The following strategies are recommended to protect you from hazardous noise:

Avoid excessive noise exposure

  • Stay away from noisy pubs, clubs, or recreational activities
  • In noisy workplace conditions, check with your employer for ways to reduce or eliminate noise at the source

Reduce the time of noise exposure

  • Limit your time in very noisy environments
  • Take 10-minute breaks from noise every half hour
  • Where possible, schedule work rotations between noisy and quiet job stations

Reduce the intensity of noise exposure

  • Use ear protection (e.g. earplugs, earmuffs)
  • Turn down the volume on music devices