Read below to get to know more abut noise pollution
Berlin is a city with a population of more than three million. With the development of urbanization,
urban noise has also become a factor affecting people's quality of life. In a big city like Berlin,
there are many noise factors, such as the construction of new facilities, or the sound people bring
in the night life and so on. The project “The Heard City” by lab:prepare uses voice and interactive
maps to illustrate the noise pollution in Berlin.
Through this project, people can better understand the factors that affect urban noise and their
characteristics. This project takes the student status as the starting point to explore the impact
of urban noise in the city of Berlin on the student population.
1.1 What is dB?
The decibel is a sound pressure level unit, but in fact it is not a unit, it is dimensionless, usually
people record it as dB. Used to indicate the size of the sound.
In the field of acoustics, dB is often used to characterize the sound pressure level. The unit of
sound pressure is Pascal, Pa, and the reference value of sound pressure is 20μPa. This value represents
the average audible threshold of the human ear at 1000 Hz. In other words, the smallest sound pressure
that humans can perceive is 20μPa.
The sound is the sound pressure fluctuation superimposed on the atmospheric pressure, the atmospheric
pressure is 1.01325×10^5Pa. Compared with atmospheric pressure, the amplitude of sound pressure fluctuates
very little. The audible sound pressure amplitude of the human ear fluctuates from 20μPa to 20Pa. This sound
pressure amplitude fluctuates in a large range, and the ratio of the two reaches 10^6. In order to easily reflect
the amplitude of this fluctuation, people introduced the concept of sound pressure level expressed in dB:
Lp= 20log10(p/p0) [dB]
Where p0 is the reference sound pressure, which is usually 20μPa in the air.
As we mentioned earlier, the audible sound pressure amplitude of the human ear
fluctuates from 20μPa to 20Pa, which can be calculated by (formula). The amplitude
dB represents the corresponding decibel number as 0~120dB. Therefore, when expressed
in decibels The size of the sound pressure level is more convenient to characterize,
and we can also feel the "size" of the sound more intuitively. 
1 decibel is about the sound that humans can hear. It is generally believed that 30-40 decibels is a relatively
quiet and normal environment; more than 50 decibels will affect sleep and rest. Interference with conversations
above 70 decibels will affect work efficiency and even accidents; long-term work or living in a noise environment
above 90 decibels will seriously affect hearing and cause other diseases.
1.2 Noise pollution in cities
There is no doubt that noise pollution is one of the major problems that humans need to face, because long-term
high-decibel noise can cause irreversible damage to the human body, which will be mentioned in 1.3. In the European
Union, about 80 million people continue to experience unacceptable noise levels (usually greater than 65 decibels),
and more than 170 million people are regularly exposed to noise levels of 55 to 65 decibels.  This article will
explore the noise of the city of Berlin. We collect from the perspective of students and draw the final conclusion
through multi-dimensional analysis.
There is no doubt that noise pollution is one of the major problems that humans need to face, because long-term
high-decibel noise can cause irreversible damage to the human body, which will be mentioned in part 1.3. In the
European Union, about 80 million people continue to experience unacceptable noise levels (usually greater than 65 decibels),
and more than 170 million people are regularly exposed to noise levels of 55 to 65 decibels.
This article will explore the noise of the city of Berlin. We collect from the perspective of students and draw the final
conclusion through multi-dimensional analysis.
The term "noise nuisance" describes the response of affected people to noise, which was recorded as a conscious
judgment during the survey. In Germany, there are federal, state and local laws regarding noise and its control.
In certain specific time periods, humans cannot make too much noise: 
Sunday and German holidays all day
Monday to Saturday (September to April) 8:00pm to 7:00am
Monday to Saturday (May to August) 9:00 pm to 7:00 am
Mowing is prohibited from 7:00 a.m. to 9:00 a.m. and after 5:00 p.m.
1:00-3:00 pm every day (Hesse; now abolished)
However, such laws usually exist in the autonomous behavior of human beings at the supervisory level. The laws and
regulations just described do not provide for the compilation of the total noise level. The German Environmental Advisory
Committee’s Document No. 490 stated that “only by comprehensively considering various noise sources can the impact of
noise pollution on the population be successfully reduced.”
The city of Berlin regularly conducts surveys on traffic noise. In the latest survey from 2017, the government surveyed the area
covering the entire Berlin state (total area of 892 square kilometers). The survey covered the noise load of 3,606,316 residents’
exposure level.  It analyzes the impact of road traffic, tram and subway traffic, air traffic, and Industry and Commerce on nearby
residents and buildings. The survey results show that road traffic is the main source of noise pollution. According to the previous
definition of "continuously suffering from unacceptable noise levels" (65dB), 40.7% of the covered population received a continuous
impact from traffic noise. Noise from air traffic and Industry and Commerce has relatively little impact on people.
1.3 Bad effects on noise pollution
Noise pollution can cause a lot of harm in all aspects. For the human body, traffic noise can cause physical and cognitive changes,
sleep disorders, and social and psychological stress. Sorensen et al. found in 2012 that for every 10 decibel increase in road traffic
noise, the risk of heart attack increased by 12%. ,  Even if noise is not enough to cause medical or psychological symptoms, it can
have a major impact on the quality of life.
As for the economy, environmental noise has attracted more and more attention as the cause of economic losses, because its cost accounts for about
0.2-2% of the GDP of developed European countries.  Therefore, it is very important to analyze urban noise to reduce its impact on humans and the economy.
2 Analysis of the noises
On the map in gehoertestadt.labpresent.de, we recorded a total of 50 time periods in different locations. These sounds correspond to the noise recorded by the students participating
in the project at different times of the day. Through the noise analysis of these times, we can roughly analyze the impact of urban noise on humans in Berlin.
According to the analysis of these 50 time points, there are indeed some different types of noise in addition to the sounds produced by normal human life. These noises mainly come from the following aspects:
1. Traffic noise
2. Life noise
3. Other noises
So next, we will focus on these three points to analyze the generation of noise and its impact.
2.2 Where do they come from ——Traffic noise?
In our records, traffic noise is the main source of urban noise. A typical example can be achieved by clicking the icon on the map: if you move the mouse to the voice recorded by Navid in Freidrichstraße,
you will clearly hear the noisy sound of SBahn on the ground. Due to the special location of Freidrichstraße station, Berlin Traffic S3, S5, S7, S9 will all stop here, so that every two or three minutes
there is a train coming from the same direction. This makes the length of the noise continuous. According to the Berlin transport operation plan, the departure interval of each train of each type of S Bahn
during peak hours is only five minutes. Generally speaking, from Sunday to Thursday, Sbahn does not operate at 1:00-4:00 at night. But on weekends, these trains will operate 24 hours a day.
This means that people living next to this station will be exposed to traffic noise 24 hours a day on weekends.
An interesting thing is that we found that traffic noise is mainly concentrated in some traffic hubs. For example, the Freidrichstraße mentioned above, or Zoologischer Garten, Ostbahnhof and so on.
It is undeniable that there is the subjectivity of choosing the place where we record the sound, which makes a relatively subjective judgment. But generally speaking, these traffic hubs will inevitably
produce continuous traffic noise. This is why there are fewer residential areas near these transportation hubs, such as Zoologischer Garten and Potsdamer Platz, because a large amount of continuous noise
is not suitable for people to live nearby for a long time. However, there are a lot of hotels near these locations. For example, near Zoologischer Garten mentioned above, there are Motel1, Waldorf and other
hotels, and there are also a lot of hotels near Potsdamer Platz and Hauptbahnhof. The same is for people to live in. Why are hotels willing to build in these places? There are two main reasons for this: one
is because of the convenience of transportation. Some tourists from other places live in these places, so they can better transfer in the city and improve tourism efficiency. The second reason is that these
hotels were constructed in a relatively new year, and the soundproofing measures of the hotels are much better than the usual residential houses in Berlin. Closing the windows can almost block the noise.
Therefore, we can make a summary of traffic noise here. From the perspective of regional division, traffic noise is mainly concentrated in the traffic hub. Relatively speaking, there are relatively few
residential buildings near these transportation hubs, mainly commercial buildings, hotels or office buildings. From a time point of view, traffic noise in Berlin exists throughout the day, because the noisy
S bahn will operate 24 hours a day from Friday to Sunday. This also proves why there are relatively few houses used by residents near these places.
2.3 Where do they come from ——Life noise?
Life noise mainly exists in our living environment. A typical example comes from the sound recorded by Stefania. You can select those time points near U Karl-Marx-Str. on the map. Those recorded sounds
are all from her. Among them, she recorded the sounds made by herself getting up at home, cooking, taking a bath, etc., and she also recorded the sounds of the WG corridor where she was. This sound is what
we call the noise of life. We can hear her roommate using things outside the door. Relatively speaking, this sound is not particularly loud. But in some special circumstances, this voice may still have some
negative effects on her (for example, she is taking an exam at home).
Generally speaking, life noise can not only be made by other people, but sometimes oneself can also make life noise that affects oneself. An example here comes from a sound of his cooking recorded by Youyou
in Spandauer Damm. Wanting to make chicken nuggets very quickly, he replaced the oven with an air fryer, which greatly shortened the cooking time. But through the recorded sound, it can be found that the air
fryer makes a lot of continuous noise: this is because of the operating mechanism of the air fryer. The air fryer is equipped with a fan to easily push small items around the cooking box, in addition to that,
it produces sound when it rotates to circulate hot air. Sometimes this noise can be as high as about 65 decibels. As we mentioned earlier, 70 decibels of noise will affect work efficiency and even accidents.
Therefore, the life noise produced by the air fryer can easily affect people. This also confirms the saying that "things have two sides''. Although the air fryer shortens the cooking time, it intensifies the noise of life.
2.4 Where do they come from ——Other noises?
In addition to traffic noise and life noise, we also found other fragmentary noises. For example, Jonas recorded the voice in Volkspark Fhain, where he apparently had a party. Or maybe it is the noise made
by the background music next to Youyou when you are working out in the gym on Tauentzienstraße. Generally speaking, these noises are short-term and controllable. Once stopped or left, these noises can be
controlled artificially. Therefore, the prevention of these noises is relatively easy. For example, wear noise-cancelling headphones when exercising, or stay away from the park to avoid the interruption of
Techno music. Therefore, I won't go into details about this kind of noise here.
2.5 Other discoveries
Before analyzing how to avoid noise and suggesting improvement measures, there are some special examples that need to be analyzed, such as a voice recorded by Jonas when he was shopping in Späti. In
this voice, there are traffic noises and life noises at the same time. We can hear from the sound recorded at night, there are the sounds of transportation and the sounds of people drinking at night.
It is worth noting that loud noises from life are not allowed to be emitted at ten o'clock in the evening. But in this sound, the traffic noise and noise from life at night must have a great impact on
the nearby residents (unless they are also making noise among the drinking crowd).
Next, we will mainly discuss how to find solutions to traffic noise and life noise.
Here, we mainly analyze the impact of traffic noise and life noise and some reasonable solutions, because these two kinds of noise can most affect the daily life of ordinary people.
3.2 Traffic noises
It can be seen from the first part and the second part that traffic noise is one of the main noises affecting human life. This is particularly reflected in the noise recorded in the central area of the city. The EU considers
the impact on health from road noise as second only to that from poor air quality. Traffic noise directly and indirectly affects people’s health. It affects our nervous and hormonal systems, thereby increasing the risk of cardiovascular
disease and impairing cognitive function. Health problems include sleep disorders, tinnitus, heart disease and increased blood pressure, as well as learning and memory disorders (especially in children).
In 2014, the European Commission passed stricter noise emission standards to encourage automakers to produce significantly quieter cars. Subsequent legislation means that from 2016 to 2026, noise limits for passenger cars, trucks, buses, buses,
and trucks will be tightened by another 3 to 4 dB(A). The new restrictions will be implemented in phases in July 2016, 2022 and 2026. The EU estimates that these measures will reduce vehicle noise by 25%.
In Paris, France, in order to reduce the noise of motorbikes such as motorcycles that are too noisy at night, the local government is trying a new system that can identify noisy vehicles, determine their location, and automatically issue fines for them.
However, this approach is still controversial, and the government needs to invest additional police force to deal with such behavior.
But overall, even if more regulations are enacted, the self-consciousness of car owners is still the most important factor.
3.3 Life noises
In addition to life noise, traffic noise may be more closely related to students' lives. Especially in the Corona period, most of the time we stayed in our own apartment, so the surrounding noise will greatly affect our lives. In student apartments, there are usually
parties that open until dawn every weekend. Many students who need a break complain about it. However, under the gloom of the epidemic, as long as there is a large-scale queue in the room, neighbors will always warn them in the notification group. After all, the epidemic
is a major topic at the moment.
For this kind of life noise caused by activities such as parties, listening to music, and practicing piano, there are the following regulations in Germany:
The so-called quiet time (German: Ruhezeit) is from 8 pm to 7 am and all day on Sundays and holidays. Light snoring is allowed, but household and gardening utensils and machinery are prohibited. No laundry at midnight or mowing on Sunday afternoon.
The state of Hessen in southern Germany used to have a quiet time between 1 pm and 3 pm every day stipulated by law. It was abolished last year, but many people will still ask you to keep it during this period. Of course, you have every right to ignore such requests. 
If you make too much noise, your neighbor has the right to call the police. Usually it starts with a warning and fines in case of repetition. For night noise, the fine is usually within three digits. However, according to the Administrative Crimes Act, the upper limit is 5,000 Euros.
 Therefore, it is best to keep quiet at night. Or if you want to listen to music loudly, please make sure you have a neighbor who is sensitive to hearing.
Noise affects our lives all the time. Our project attempts to analyze whether there is any connection between them by recording the noise in the city of Berlin. Although there are still many shortcomings. If we have an instrument that can measure decibels, it will be more helpful
for us to analyze the absolute magnitude of noise. Such a measurement method is also mentioned in the first part of the Berlin government's method of noise measurement. Of course, instruments such as AppleWatch can better measure the decibel value. In addition, the number of samples
for this project is limited. Therefore, we limited the survey subjects to students to record the impact of noise on students living in Berlin.
In order to prevent noise, apart from the government using laws to restrict it, we can also prevent it to a certain extent. For the noise of life at night, humans can prevent the noise from entering by wearing earplugs. Another example is the Apple Watch mentioned above. When the
decibel value of a person’s environment continues to exceed 90dB, the watch will warn the wearer to prevent the individual from being in a high-decibel environment for a long time, thereby preventing noise from being affected by humans. Physical injury.
In short, we need to control the excessive spread of urban noise through the efforts of the government and individuals, through laws or personal actions, so as to reduce the harm of noise to the human body.
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 ARAG, So vermeiden Sie Ärger durch Ruhestörung