I hear this sentence too often. It reveals a firmly rooted belief: we get used to noise. However, it has long been proven that noise impacts us.
Indeed, as we will see later, the effects of noise on health are considerable. Even if we feel like we are getting used to it, our brain constantly perceives surrounding sounds.
When we no longer perceive a constant noise, it is not because it has disappeared, but because our brain filters it unconsciously. It plays the role of an "earplug" by attenuating some of the sounds to allow us to focus on other stimuli.
But the impact of ambient noise is very real.
Every year, an ADEME study evaluates the cost of noise in France.
In 2021, its estimate stands at 147,1 billion per year !
This exorbitant cost is divided as follows:
The table below, taken from the 2021 ADEME report, illustrates the scale of the problem linked to road noise.
LDEN = 24 hour average
LN = average from 22 p.m. to 6 a.m. (night noise)
source: ADEME's Social Cost of Noise in France 2021
Unlike a linear scale, where each increment represents a constant increase, the decibel scale reflects the way our ears perceive sounds. Physics tells us that if we let's increase by 3 dB a sound, it's like the noise source is doubled !
For example, if a fan emits 50 dB and we add another one, the second fan will emit 3 dB, making a total of 53 dB for the two fans! As a result, a sound of 70 dB is perceived much louder than a sound of 60 dB….
For everyday life, the WHO recommends not to exceed an ambient noise level of 53 dB (A) during the day to avoid significant inconvenience. and 45 dB (A) at night to ensure quality sleep. These recommendations are based on studies showing that Cardiovascular risks increase from 50 dB of prolonged exposure (WHO, 2018).
Yet we can read it on the table above, 61.3% of the population is exposed to road noise of more than 55 dB(A) during the day and 58 % are exposed to more than 45dB(A) at night…
When we talk about noise, we first think of the effects on hearing. It is true that intense noises, even of short duration, can cause a hearing loss, even a hearing loss, hyperacusis (hypersensitivity to sounds, disabling in daily life) or tinnitus (persistent whistling or buzzing noises).
But the effects of noise go far beyond hearing.
Prolonged exposure to noise pollution can lead to:
The infographic below, taken from the ADEME study, summarizes the impacts of transport noise on health in France.
Fortunately, the state of knowledge on the effects of noise on health is improving, both in France and internationally. Through studies and numerical demonstrations, the consideration of noise is evolving, including in the media.
In particular, WHO has revised upwards its 2018 recommendations on environmental noise for the European region.
At the national level, the collection and structuring of data has also improved significantly, thanks to the creation of a database of populations exposed to noise, managed by the CEREMA (Center for studies and expertise on risks, the environment, mobility and planning) based on information communicated by large urban areas and the services of the departmental territorial directorates, responsible for approving strategic noise maps.
Awareness is growing and some cities are taking specific measures to limit exposure to noise:
Reducing the impact of noise on health also requires collective awareness:
However, in the current organization of society, it is difficult to quickly reduce certain sources of noise, such as transport or construction sites. This is why the development of high-performance insulating materials is essential.
Good sound insulation of the buildings (housing, schools, offices) can protect the population from the harmful effects of noise. By integrating these solutions into urban planning and architecture, we can mitigate noise pollution and its consequences on health.
Our job at Impulsion Acoustique is to help manufacturers of insulation materials optimize the acoustic performance of their products. Because we know how much noise disrupts our lives!
Noise is an invisible scourge, whose impacts on health are still underestimated. However, it affects millions of people on a daily basis, increasing stress, fatigue and the risk of chronic diseases.
Fortunately, solutions exist: rethought urban planning, stricter regulations, innovation in insulating materials... But it is also a collective awareness that will make the difference. After all, Silence is not a luxury, but a necessity for our well-being.
