Noise: health effects

Noise is part of everyday life, especially in cities, and almost everyone is bothered by loud noises now and again. At the same time, exposure to noise can cause stress, especially if it is persistent. Research conducted over the last decade shows that noise is one of the primary environmental risks to physical and mental health.

Many people are affected by persistent noise: 75 percent of people in Germany are bothered or annoyed by the noise of road traffic in the area where they live, 60 percent by the volume of their neighbors, 42 percent by aircraft noise and 35 percent by rail traffic noise.

All noise spreads as sound waves. The strength of these sound waves – the sound pressure level or volume – is expressed in decibels (dB). The hearing threshold is one decibel, i.e. this is the volume of the quietest sounds that people can hear. If a noise is 10 decibels louder, it is perceived as twice as loud.

Noise at night is generally perceived as more bothersome and annoying than during the day. For example, the noise of airplanes can bother people and damage their health from an average of 40 decibels at night but about 45 decibels during the day.

Loud noises can not only directly damage hearing but also be indirectly harmful to physical and mental health.

Direct effects on hearing

The hearing can be damaged by short, very loud sound pulses over 130 decibels – for example very close thunder – or long-lasting loud noises. For instance, the hearing can be restricted and muffled after a concert (about 90 to 120 decibels). Buzzing or whistling noises may temporarily affect the ears or lead to tinnitus. This is when a person hears a constant whistling or humming without any external reason.

If very loud sounds damage the hair cells in the inner ear, certain sound waves are no longer transmitted to the brain. In particular, high tones (with a high sound frequency) often damage these hair cells. Such noises include explosions or shots near the ear, for example caused by fireworks on New Year’s Eve. They can rupture the eardrum, the thin piece of skin that separates the ear canal and the middle ear, although this usually grows back together again. As damaged hair cells do not recover, however, permanent hearing damage may ensue, i.e. hearing impairment.

In addition to the above, impaired hearing can also be caused by a permanently high level of exposure to noise, for example at work. People with certain jobs, e.g. on building sites, are exposed to high volumes at work.

Indirect health effects

Environmental noise does not usually directly damage the hearing. Nevertheless, persistent noise from airplanes and cars in particular can lead to chronic stress reactions and increase the risk of a number of health issues including sleep disorders, cardiovascular diseases and strong feelings of noise-induced anger. The noise-induced stress reactions also occur when people are sleeping and in people who believe that they have become accustomed to noise.

There are various forms of general noise protection. For example, to reduce the annoyance of traffic noise, more 30 km/h speed zones and quiet zones are being introduced in cities, noise barriers are being installed and quieter materials are being developed for car and motorcycle tires. The increase in the use of electromobility and the promotion of other environmentally friendly transport means like bicycles also play an important role. In many cases, it is also possible for people to individually protect themselves against noise.

Hearing protection

Wear certified hearing protection during loud activities or at loud events, for example when mowing the lawn, at concerts or on New Year’s Eve. Ear plugs may help at night.

Pay attention to your environment

Check every now and again if you find the noises in your everyday environment pleasant or bothersome. Do they bother you? Then do something about them. Are you still enjoying listening to the music in the background or could you turn that off too? Do you find the ticking of the clock or the loud humming of the refrigerator annoying?

Ask for quiet

If you share a room with other people and they are too loud, ask them to be quieter. If nearby colleagues persistently talk loudly on the phone, this can be annoying and stressful.

Find quiet places

If you live in the city, try to choose routes along smaller roads or through parks when going for a walk or heading to work. Spend more of your free time in quiet places, such as forests.

Noise can be differently perceived and cause people different levels of stress. Some people are also exposed to more noise pollution than others due to where they live, for example on busy roads.

Noise perception

In many cases, whether loud noises bother people depends on how they are perceived. A group of young people is having a great time listening to loud music. A neighbor hears the same music much more quietly from next door. However, she gets annoyed because she cannot sleep and has to be up early for work the next day. One and the same noise can be perceived by one person as annoying and another as desired.

Noise sensitivity

Sensitivity to noise varies from person to person. People who are more sensitive to noise find that it causes them more stress. In the long term, being subjected to noise can do these people more damage than those who respond less sensitively to it.