Even if the noise is only 85 decibels, 10% people will be deaf; 120~ 130 db noise can make people feel ear pain; Strong noise will damage the hearing organs. In the nervous system, strong noise can cause headache, dizziness, burnout, insomnia, emotional anxiety, memory loss, increased EEG slow waves, autonomic nervous system dysfunction and other symptoms. In the cardiovascular system, strong noise will cause changes in pulse and heart rate, elevated blood pressure, arrhythmia, conduction block, changes in peripheral blood flow and so on. In the endocrine system, strong noise will cause hyperthyroidism, adrenal cortex function enhancement, basal metabolic rate increase, sexual dysfunction, menstrual disorder and so on; In the digestive system, strong noise will cause digestive dysfunction, gastric dysfunction, gastric acid reduction, loss of appetite and so on. In a word, strong noise will lead to a series of physiological and pathological changes in human body. 202 people working in the environment with noise as high as 95 decibels were investigated. The results showed that dizziness accounted for 39%, insomnia for 32%, headache for 27%, stomachache for 27%, palpitation for 27%, memory loss for 27%, upset for 22%, poor appetite for 18% and hypertension for 18%. Therefore, we should not take strong noise for granted, and take measures to prevent it. Of course, people are sensitive to noise, and there are great differences among individuals. Some people are sensitive to noise, and some people have strong adaptability to noise, which is also related to psychological factors such as people's needs and emotions. No matter how different people are, strong noise always needs to be prevented.
Long-term exposure of pregnant women to noise exceeding 50 decibels will lead to endocrine gland dysfunction, mental stress and endocrine system disorder. Serious will raise blood pressure, fetal hypoxia and ischemia, leading to fetal malformation, and even abortion. Moreover, high decibel noise will damage the fetal hearing organs, causing some areas to be affected. It affects the development of the brain and leads to mental retardation in children.
The malignant stimulation of noise seriously affects our sleep quality, which will lead to neurasthenia symptoms such as dizziness, headache, insomnia, dreaminess, memory loss, inattention, and digestive tract symptoms such as nausea, vomiting, stomachache, bloating and loss of appetite. Nutritionists have found that noise can also increase the consumption of vitamins, amino acids, glutamic acid, lysine and other trace elements in the human body, affecting health; Noise increases adrenal gland secretion, heart rate and blood pressure, which easily leads to heart attack; At the same time, noise can reduce the secretion of saliva, gastric juice and gastric acid, thus suffering from gastric ulcer and duodenal ulcer.
It affects people's nervous system and makes them irritable.
Affect sleep and cause fatigue.
In order to prevent noise, Professor Ma, a famous Chinese acoustics scientist, summarized and studied the hazards and standards of various noises at home and abroad, and put forward three suggestions: (1) In order to protect people's hearing and health, the allowable value of noise is 75~90 dB.
(2) Ensure conversation and communication, and the allowable value of environmental noise is 45~60 decibels.
(3) It is recommended to sleep at 35~50 decibels.
The impact and harm of noise on people are directly related to the intensity of noise. In buildings, the measures to reduce noise are mainly sound insulation and sound absorption. Sound insulation is to isolate the sound source and prevent the noise generated by the sound source from spreading indoors. Planting trees on both sides of the road can insulate the houses on both sides. The sandwich structure made of porous materials and dense materials will also have good sound insulation effect. In order to eliminate noise, commonly used sound-absorbing materials are mainly porous sound-absorbing materials, such as glass wool, mineral wool, expanded perlite, perforated sound-absorbing board and so on. The sound absorption performance of materials depends on its roughness, flexibility, porosity and other factors. In addition, lawns and trees around buildings are also good sound-absorbing materials, so we plant flowers and trees, which not only beautify our living and learning environment, but also prevent noise from polluting the environment.
Psychologists in China believe that besides human factors, economic and technical feasibility should also be considered in controlling noise environment. Adequate noise control must consider the whole system composed of noise source, sound propagation mode and sound receiver. Noise control measures can be aimed at the above three parts or any of them. The contents of noise control include: (1) reducing sound source noise. Industry and transportation industry can choose low-noise production equipment and improve production technology, or change the motion mode of noise source (such as reducing the vibration of solid sound generator through damping and vibration isolation). (2) Reduce the noise in the sound propagation path, control the noise propagation, change the noise propagation path that has been emitted by the sound source, such as taking measures such as sound absorption, sound insulation, sound barrier and vibration isolation, and rationally plan the layout of cities and buildings. (3) When the noise protection of the receiver or the receiver fails to take measures in terms of sound source and transmission route, or the acoustic measures still fail to achieve the expected effect, it is necessary to take protective measures for the receiver or the receiver. For example, workers who have been exposed to occupational noise for a long time can wear ear protectors such as earplugs, earmuffs or helmets.
Although noise control is technically mature now, many enterprises and places adopt noise control because of the large scale of modern industry and transportation. Therefore, in the aspect of noise prevention, we must make a comprehensive balance from the aspects of technology, economy and effect. Of course, specific problems should be analyzed in detail. In outdoor, design room, workshop or places where employees work for a long time, the noise intensity should be low; Warehouses or workshops with few people or open places are slightly noisy. In a word, the treatment of noise should be different at different time, place, nature and duration.
(1) Strengthen the prevention and control of traffic noise pollution, and fully implement the technical policy for the prevention and control of ground traffic noise pollution. In the elevated roads, expressways, expressways, urban rail and other roads concentrated in noise-sensitive structures (hereinafter referred to as "sensitive areas"), sound barriers will be built, and measures such as no ringing, current restriction and speed limit will be strictly implemented. Accelerate the construction of urban railway crossings to interchanges, and gradually cancel the urban grade crossing. Control the noise pollution of urban high-speed rail operation. Strengthen the prevention and control of noise pollution around the airport and reduce disputes over aviation noise disturbing people.
(2) Strengthen the prevention and control of construction noise pollution, strictly enforce the boundary noise limit of construction sites, and investigate and deal with the excessive emission of construction noise. Strengthen the management of construction noise emission declaration and implement the environmental protection announcement system for urban construction. The people's government of the city shall limit the construction time according to law and strictly limit the construction work that produces noise pollution in sensitive areas at night. Implement the examination and approval management of urban night construction, popularize the automatic noise monitoring system to supervise construction in real time, and encourage the use of low-noise construction equipment and technology.
(three) to promote the prevention and control of noise pollution in social life, strictly implement the community noise emission standards, and prohibit commercial activities from using audio equipment outdoors to attract customers. Strictly control the noise pollution of processing, maintenance, catering, entertainment, fitness, supermarkets and other commercial services, effectively control the noise pollution of cooling towers, elevators, water pump rooms, air conditioners and other supporting service facilities, and strictly manage cultural and sports activities and indoor entertainment activities in sensitive areas. Actively promote the urban indoor comprehensive market and ban the open-air or road market that disturbs people. Strict management of indoor decoration, clearly limit the operation time, and strictly control the decoration operation of noise generated by completed residential buildings. Strengthen the green nursing work during the national examinations such as the senior high school entrance examination and create a good examination environment for candidates.
(4) Deepen the prevention and control of noise pollution in industrial enterprises, implement environmental noise emission standards at the boundary of industrial enterprises, and investigate and deal with noise exceeding the standard to disturb people. Intensify efforts to close pollution sources with excessive noise in sensitive areas. Cities should shut down, relocate and control a number of enterprises with serious noise pollution every year, and realize the noise emission standard of industrial enterprises in sensitive areas before the end of 20 15. Strengthen the prevention and control of noise pollution in industrial parks and prohibit high-noise pollution projects from entering the park. Carry out noise pollution prevention and control in rural industrial enterprises.