Indoor environmental pollution caused by decoration and its prevention-indoor harmful gas pollution and prevention-indoor harmful gas pollution and prevention Abstract: Indoor decoration and decoration have seriously threatened human life and health. It is urgent to carry out real-time and accurate detection and effective control and treatment of pollution sources. Here, the sources and causes of indoor harmful gas pollution caused by decoration are expounded in detail. Harmful gas pollution; According to statistics, modern people spend more than 80% of their time indoors [1], 2.8 million people in the world died directly or indirectly from decoration pollution, and about 4% of the diseases in the world are related to the indoor environment [2]. Decoration pollution has been listed as one of the five major environmental problems that endanger public health. With the improvement of people's living standards, room decoration has become a hot spot of consumption. However, the quality of decoration materials in the market is uneven, and the content of harmful substances in some decoration and repair materials seriously exceeds the standard, which brings pollution to indoor air, and various diseases caused by it seriously affect people's physical and mental health [3]. Many indoor air pollutants are irritating gases, such as sulfur dioxide and formaldehyde, which will irritate eyes, nose, throat and skin and cause symptoms such as tears, cough and sneezing. What's more, living in polluted air for a long time will also lead to the decline of respiratory function and the aggravation of respiratory symptoms, and some will also lead to chronic bronchitis, bronchial asthma, emphysema and other diseases, and the incidence of lung cancer and nasopharyngeal carcinoma will also increase. Knowing the source and harm of indoor pollutants is helpful for us to choose green building materials reasonably and control the existing indoor pollutants. Sources of Indoor Harmful Gases and Harmful Sources of Indoor Harmful Gases At present, the main pollution sources of indoor environment in China come from buildings, decoration and furniture. With the improvement of people's living standards, more and more people begin to pay attention to home decoration, and toxic substances in home decoration materials are an important cause of indoor pollution. The five major pollution sources of indoor decoration are formaldehyde, benzene, ammonia and radon. Total volatile organic compounds (TVOC)[4]. The sources and hazards of the five major pollution sources are mainly introduced as follows: (1) formaldehyde. Formaldehyde (HCHO) is an organic compound with strong pungent smell, which is easily soluble in water, alcohol and ether. Its 40% aqueous solution is called "formalin", which is recognized as an effective disinfectant and is very useful as a chemical substance. At present, formalin is still used as a preservative in medicine. Formaldehyde has strong adhesion, which can prevent insects, prevent corrosion and enhance the hardness of plates. Formaldehyde in indoor air mainly comes from plywood, blockboard, fiberboard, particleboard and wood furniture made of man-made board. Other decorative materials, such as chemical fiber carpets, paints, wallpapers and plastic foams, paints and some organic materials also contain a certain amount of formaldehyde. However, if people often come into contact with this volatile organic compound, it will do harm to human health. Formaldehyde is mainly harmful to the respiratory system and has been identified as a suspected carcinogen or substance by the World Health Organization. Benzene and benzene series (2) Benzene and benzene series, which are colorless and transparent liquids, have a special aromatic smell, are less dense than water, are insoluble in water, and are often used as organic solvents. Benzene series include benzene, toluene and xylene. Benzene exists in paints, adhesives, coatings and putty. Benzene and benzene series are also identified as carcinogens by the World Health Organization. People who inhale high concentrations of toluene and xylene in a short time will have symptoms of central nervous system anesthesia, ranging from dizziness, nausea, chest tightness and fatigue to coma, leading to respiratory failure and death. Benzene is mainly harmful to skin and irritating to eyes and upper respiratory tract. People who have been exposed to benzene mixtures for a long time have a high incidence of aplastic anemia, which can cause leukemia. Inhaling a large amount of toluene in pregnant women may lead to fetal malformation, central nervous system dysfunction, growth retardation and other defects [5]. (3) Ammonia, a colorless volatile alkaline gas, has strong irritation, is lighter than air and has high solubility. It mainly comes from concrete additives used in construction, such as antifreeze and expansion agent. Adhesives, coating additives and brighteners in building decoration materials. Ammonia is highly soluble and easily soluble in water in the upper respiratory tract, so only a small part can reach lung tissue after inhalation. It will cause irritation to eyes, respiratory tract and skin and damage the nervous system, reproductive system and respiratory system. Long-term severe exposure can lead to lung cancer. (4) Radon, a colorless and odorless radioactive odor, can be dissolved in water and some organic solvents. It is the product of uranium decay in rocks and soil. Mainly from inorganic materials (granite, marble, gypsum, cement, sand, etc. ) products mainly made of natural stone, slag and industrial waste residue. Radon will enter people's respiratory system, causing radiation damage and inducing lung cancer. It will also affect people's nervous system, making people feel sluggish and sleepy. Exposure to high concentrations of radon and its decay products will increase the chance of inducing lung cancer. Under the action of high dose radiation, it may cause skin cancer and leukemia [6]. TVOC (5), Total Volatile Organic Compounds (TVOC) is a general term for compounds that are composed of one or more carbon atoms and are easily evaporated at normal temperature and pressure. They are colorless gases existing in indoor environment, which are emitted from building materials, detergents, cosmetics, wax products, carpets, furniture, laser printers, copiers, adhesives and indoor coatings, and have toxic effects on central nervous system, liver, kidneys and blood. Short-term contact can make eyes uncomfortable: burning, dryness, foreign body sensation and edema; Sore throat: dry throat; Respiratory system problems: shortness of breath, asthma, headache, anemia, dizziness, fatigue, irritability, etc. Third, the prevention and control of harmful gases in home decoration should be green, not absolutely pollution-free, but try to reduce pollution. Any decoration will cause pollution, but as long as the pollution level does not exceed the standard range stipulated by the state, it will not cause harm to the human body. First of all, the design of home decoration should be simple and practical, and indoor air circulation should be considered when designing. If the room design is closed and the ventilation is not smooth, it will not be conducive to the elimination of harmful substances. When selecting materials, we should also strictly choose safe and environmentally friendly materials, be sure to pay attention to whether there are green signs of environmentally friendly products, and try to choose materials with less irritating smell. In the construction, we should also pay attention to the choice of non-toxic, less toxic, pollution-free and less polluting construction technology, and should choose a regular decoration company for construction. Ensure green safety in the construction process. Secondly, if air pollution is found after renovation, control measures should be taken in time. Common control methods include physical adsorption, chemical adsorption and photocatalyst. Physical adsorption is to absorb harmful gases by using the porous and microporous adsorption of inorganic substances such as activated carbon, porous aluminosilicate and alumina. It has a certain effect. However, physical adsorption method is often only effective for specific substances and is greatly affected by the environment. Chemical adsorption uses specific chemical reactions to convert harmful gases into other substances. The main products sold in China's market are formaldehyde scavenger, ammonia deodorizer and benzene eliminator, which can purify formaldehyde, ammonia and benzene respectively. However, it should be noted that although these chemicals can play a certain role, they may also produce secondary pollution. Or the harmful gas will rebound again if it is not completely removed. Under the irradiation of light, the photocatalyst centered on nano titanium dioxide will produce a photocatalytic reaction similar to photosynthesis, producing free hydroxyl and active oxygen with strong oxidation ability, which can oxidize and decompose various organic compounds and decompose organic pollutants into pollution-free water and carbon dioxide. At the same time, it is a good way to remove decoration pollution, and there is no problem of secondary pollution. Photocatalyst also has the functions of sterilization, deodorization, mildew prevention, self-cleaning and air purification. , can improve indoor air quality in an all-round way. 4. Conclusion Indoor decoration not only brings people beautiful enjoyment, but also brings some pollution. The pollution of harmful gases in indoor environment is closely related to everyone. Recognizing the source and harm of pollutants will help us to prevent pollution and protect our health while enjoying the beauty.