What Noises Cause Hearing Loss?
Noise is a significant source of hearing loss, but you can protect your hearing. An important first step is to understand how noise causes hearing loss.
Hearing loss can result from a single loud sound (like firecrackers) near your ear. Or, more often, hearing loss can result over time from damage caused by repeated exposures to loud sounds. The louder the sound, the shorter the amount of time it takes for hearing loss to occur. The longer the exposure, the greater the risk for hearing loss (especially when hearing protection is not used or there is not enough time for the ears to rest between exposures).
Here are some sources of loud noise that you may be exposed to. If you are repeatedly exposed to them over time, they can cause hearing loss.
- Music from smartphones and personal listening devices, particularly when the volume is set close to the maximum
- Fitness classes
- Children’s toys
- Concerts, restaurants, and bars
- Sporting events, such as football, hockey, and soccer games
- Motorized sporting events, such as monster truck shows, stock car or road races, and snowmobiling
- Movie theaters
- Power tools
- Gas-powered lawnmowers and leaf blowers
Sound is measured in decibels (dB). A whisper is about 30 dB, normal conversation is about 60 dB, and a motorcycle engine running is about 95 dB. Noise above 70 dB over a prolonged period of time may start to damage your hearing. Loud noise above 120 dB can cause immediate harm to your ears.
The table below shows dB levels and how noise from everyday sources can affect your hearing.
|Everyday Sounds and Noises
|Average Sound Level (measured in decibels)
|Typical Response (after routine or repeated exposure)
|Softest sound that can be heard
Sounds at these dB levels typically don’t cause any hearing damage.
|Normal conversation, air conditioner
|Washing machine, dishwasher
|You may feel annoyed by the noise
|City traffic (inside the car)
|You may feel very annoyed
|Gas-powered lawnmowers and leaf blowers
|Damage to hearing possible after 2 hours of exposure
|Damage to hearing possible after about 50 minutes of exposure
|Approaching subway train, car horn at 16 feet (5 meters), and sporting events (such as hockey playoffs and football games)
|Hearing loss possible after 15 minutes
|The maximum volume level for personal listening devices; a very loud radio, stereo, or television; and loud entertainment venues (such as nightclubs, bars, and rock concerts)
|Hearing loss possible in less than 5 minutes
|Shouting or barking in the ear
|Hearing loss possible in less than 2 minutes
|Standing beside or near sirens
|Pain and ear injury
|Pain and ear injury
The time estimates listed in the “Typical Response” column are based on the NIOSH exchange rate of 3 dB. For more information, visit NIOSH’s website.
How loud something sounds to you is not the same as the actual intensity of that sound. Sound intensity is the amount of sound energy in a confined space. It is measured in decibels (dB). The decibel scale is logarithmic, which means that loudness is not directly proportional to sound intensity. Instead, the intensity of a sound grows very fast. This means that a sound at 20 dB is 10 times more intense than a sound at 10 dB. Also, the intensity of a sound at 100 dB is one billion times more powerful compared to a sound at 10 dB.
Two sounds that have equal intensity are not necessarily equally loud. Loudness refers to how you perceive audible sounds. A sound that seems loud in a quiet room might not be noticeable when you are on a street corner with heavy traffic, even though the sound intensity is the same. In general, to measure loudness, a sound must be increased by 10 dB to be perceived as twice as loud. For example, ten violins would sound only twice as loud as one violin.
The risk of damaging your hearing from noise increases with the sound intensity, not the loudness of the sound. If you need to raise your voice to be heard at an arm’s length, the noise level in the environment is likely above 85 dB in sound intensity and could damage your hearing over time.
The effect of lower noise levels over long periods is the same as louder noise levels over a shorter period. You can use a sound level meter (SLM) to measure noise around you. Free SLMs developed as smartphone apps are available. Some of these apps can predict your maximum allowable daily noise dose, like the NIOSH SLM app developed for iOS devices to help promote better hearing health and prevention efforts. The U.S. Environmental Protection Agency (EPA) and the World Health Organization (WHO) recommend maintaining environmental noises below 70 dBA over 24-hours (75 dBA over 8-hours) to prevent noise-induced hearing loss. The EPA also specified limits for speech interference and annoyance at 55 dBA for outdoors activities and 45 dBA for indoor activities. More details about this topic can be found on the NIOSH Science Blog — Understanding Noise Exposure Limits: Occupational vs. General Environmental Noise.
If you are looking for data on noise levels from published studies and noise level tests, visit