Ozone (chemical formula O3), also known as triatomic oxygen, is named after its fish-like odor.
The chemical properties of ozone are extremely active. When it is free, its energy produces powerful oxidation in an instant, and performs sterilization, disinfection, and detoxification work.
When the content of ozone in the air is within one part per million, it is very beneficial to the human body, because trace amounts of ozone can stimulate the central nervous system, accelerate blood circulation, increase the amount of active oxygen in the blood, and activate cells. However, High concentrations of ozone can make people feel uncomfortable and even cause reversible damage to the human body.
But the existence time of ozone is very short (about 30 seconds) because excess ozone can quickly decompose into oxygen.
The air contains about 0.02PPm of ozone. Under normal circumstances, 1PPm of ozone in the air is 2.14mg/m 3 and 1PPm of ozone in the water is 1mg/L. Long-term breathing of >0.1PPm ozone is harmful to the human body. When the ozone concentration is 0.02PPm, people with a keen sense of smell can feel it, which is called the "sense critical point"; when 0.15PPm, ordinary people can smell it, which is called the "olfactory critical value" (also the health standard point); 1-10PPm is the "irritation point" "range"; above 10PPm is the "poisoning range".
Ozone is a strong oxidant. The ozone sterilization process is a biochemical oxidation reaction. There are three ways to sterilize O 3: Ozone can oxidize and decompose the enzyme necessary to oxidize glucose inside the bacteria, killing the bacteria. Living death. Directly interacts with bacteria and viruses, destroying their cell walls, DNA and RNA. The metabolism of bacteria is damaged, leading to death. (DNA - ribonucleic acid; RNA - deoxyribonucleic acid. Viruses are macromolecules with a type of nucleic acid wrapped in protein; viruses contain only one type of nucleic acid. Excerpted from "Basics of Microbiology", Chemical Industry Press, 1994 edition). Penetrates the cell membrane tissue, invades the cell membrane, and acts on the lipoproteins in the outer membrane and the lipopolysaccharide inside, causing the bacteria to undergo permeability distortion, dissolve and die
Ozone has oxidative properties on objects, mainly natural rubber or Natural rubber products and copper products (when moisture is present) are subject to certain corrosion.
There are many ways to generate negative ions, and the most commonly used method is the corona discharge method (as shown in the picture). It uses a non-uniform electric field between a needle electrode and a flat electrode under the action of high voltage to ionize the flowing air. In the picture, a negative high-voltage pulse is applied to the thin metal wire to ionize the air next to the thin wire. Positive ions are absorbed on the thin wires, while negative ions move toward the metal mesh electrodes. Under the action of wind, the negative ions are taken away from the metal mesh holes. The amount of ions generated is related to the wind speed. The usually used wind speed is less than 10m/s, the pulse voltage is generally 50kV, and the pulse frequency is 50Hz. When the input power is 50W, the number of ions generated is about 5x1010-5x1011/s.
Air ions have a certain impact on human health. Ions in the atmosphere can be divided into three major categories: (1) Light ions - they are a single-charged aggregate composed of several neutral molecules. Negatively charged light ions are usually called negative ions; positively charged light ions are called positive ions. (2) Medium ion: It is also a small charged particle, containing about 100 gas molecules. (3) Heavy ion: It is a larger charged particle, about 1000 times larger than light ions.
Heavy ions in the air are easy to collect and eliminate, and the number is very small after air purification treatment. Of significance to air conditioning engineering are light ions and medium ions. Because there are generally a small number of light ions in the outdoor air, and in cities due to air pollution, light ions are often lacking, making medium ions the main component in the air. Air-conditioned rooms generally require a small number of light ions, especially negative ions. Because negative ions can have a calming effect on the human body's nervous system, promote the elimination of fatigue, inhibit asthma, and lower blood pressure. The life of light ions is very short. During the air heating, cooling and filtration processes, light ions will disappear quickly after contact with the metal surface. Therefore, if no measures are taken, the light ion density in the air-conditioned room will be reduced by half that of the outdoor air.
In order to improve sanitary conditions, a negative ion generator should be installed in the air-conditioned room.
There are many ways to generate negative ions, and the most commonly used method is the corona discharge method (as shown in the picture). It uses a non-uniform electric field between a needle electrode and a flat electrode under the action of high voltage to ionize the flowing air. In the picture, a negative high-voltage pulse is applied to the thin metal wire to ionize the air next to the thin wire. Positive ions are absorbed on the thin wires, while negative ions move toward the metal mesh electrodes. Under the action of wind, the negative ions are taken away from the metal mesh holes. The amount of ions generated is related to the wind speed. The usually used wind speed is less than 10m/s, the pulse voltage is generally 50kV, and the pulse frequency is 50Hz. When the input power is 50W, the number of ions generated is about 5x1010-5x1011/s.
The world's leading high-purity air negative ion technology is the "ion converter" technology invented by the Japanese scientist Noboru Horiguchi, MD, known as the "first person in negative ions". It is manufactured using the earth's natural resources. Patented technology equivalent to natural air negative ions. The negative air ions produced by it are no different from those produced by nature. They are very suitable for regulating human body functions and play a significant role in improving physical fitness and maintaining health.
The introduction of this technology will bring the world's most advanced environmental improvement equipment to Chinese customers, which will be able to meet the needs and tastes of China's most discerning building owners, families and car owners. With the release of the Salumi series of products, the definitions of top-notch central air-conditioning environment improvement equipment and negative ion devices for homes and cars have been updated again.
*So are ozone and negative ions useful?
Ozone technology and negative ion technology have been used in indoor air purification and management. A certain concentration of ozone and negative ions are beneficial to disinfection and sterilization and the human body. The reason why it was eliminated is because the sterilization and disinfection function of ozone is a "double-edged sword". It kills viruses indoors and harms the human body at the same time. If the amount of ozone released is reduced, it will not have the sterilization and disinfection effect. Furniture and wall and floor surfaces near the ozone machine will also suffer. Under certain humidity conditions, ozone is slightly corrosive to metal surfaces, rubber materials, paint materials, and wood products.
The negative ion generator also uses the high-voltage electrode corona principle to generate negative ions, and it will also produce a certain amount of ozone. Since negative ions exist in the air for a shorter time than ozone, the release of ozone is out of control while producing negative ions for a long time.
Most people will be misled by the functions of these two. They rely on "robbing" indoor oxygen to create ozone, which is also used to sterilize and decompose harmful oxidative substances. Then the amount of indoor oxygen will decrease. Since the sterilization effect of ozone is slightly higher than that of ultraviolet light, ozone technology is generally used in water treatment, and it must go through a filtration process after sterilization, because bacterial corpses are also a breeding ground for bacterial viruses.
According to a report in the American "Live Science" magazine on May 10, a latest study led by Sergei Nizkorodov, a professor in the Department of Chemistry at the University of California, Irvine, proved that when using In a room with an air purifier, the ozone concentration can easily exceed the standard.
Nizkorodov and his colleagues tested homes, offices and cars using various air purifiers and found that ozone concentrations in these locations exceeded California's basic safety standards. If outdoors, this concentration would trigger a Level 2 smoke pollution alarm.
In recent years, indoor pollution has attracted much attention, making air purification devices popular. Manufacturers generally claim that they can filter dust, eliminate odors and harmful gases, and that their chemical reactions will only produce by-products such as carbon dioxide, ozone, and water that are harmless to health. The U.S. Environmental Protection Agency said in a report: “In fact, the merchants’ propaganda is misleading consumers and is an irresponsible behavior.
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In the interview, researcher Cui Jiusi from the Environmental Health Monitoring Institute of the Chinese Academy of Preventive Medicine introduced the working principle of the ionic air purifier to reporters: first charging the air pollution particles, and then adsorbing them to the metal electrodes In this process called "ionization," air purifiers emit ozone as a by-product, especially in small rooms with poor ventilation.
According to the American "Air and Waste Management Association Magazine", when ozone is in the upper atmosphere, it can block ultraviolet rays and protect earth organisms; but close to the ground, it is a dangerous pollutant that can It can harm people's lungs, causing shortness of breath, throat inflammation, asthma attacks, etc.
Researcher Cui Jiusi said that controlling indoor pollution cannot rely entirely on air purification equipment, but must focus on the sources of pollution in the home and decorate it. When purchasing new furniture, you should control the content of pollutants to a minimum and open windows frequently for ventilation.
Introduction: A collection of opinions and evaluations of ozone by famous domestic experts.
“The principle of ozone being used for disinfection is that people are not in the condition. When the concentration of ozone in the air is 0.04~0.09mg/m3, people can smell it. The "Industrial Hygiene Standards" formulated by the Ministry of Health of my country stipulates that the safety standard for ozone is 0.32mg/m3, and the standard of the International Ozone Association is 0.21 mg/ Work under m3 for 8 to 10 hours. Even at this concentration, people will have a slight mouthfeel. Most people will experience dry mouth and discomfort when exposed to 1.12-2.1 mg/m3 for 15 hours; coughing and fatigue after 1 hour of exposure to 2.1-4.3 mg/m3; 45-minute exposure to 4.3-6 mg/m3 can cause severe coughing; 10.7-21.4 mg/m3, it can cause rapid pulse, fatigue and headache. Emphysema and even death can occur after 1 hour of exposure. …. There have been reports in China of cases of allergies to low-concentration ozone, manifesting as symptoms such as cough, chest tightness, shortness of breath, difficulty breathing, and rapid pulse. "——"Modern Disinfection" P359, Xue Guangbo. Professor of Epidemiology and Disinfection at the Second Military Medical University
"The toxicity of ozone mainly comes from the oxidation of proteins and fatty acids, thereby damaging body tissues. Animal tests show that the starting point concentration of toxicity is 0.3ppm (0.6mg/m3), while the human olfactory sensing concentration of ozone in the air is 0.02~0.04ppm (0.04~0.08mg/m3). Exposure to 0.5~1.0ppm ozone for 1.5 hours can cause dry mouth and cough; high concentration and long exposure time can cause strong respiratory symptoms. Ozone gas can cause harm to the human body and is significantly irritating to the respiratory mucosa, especially the lung tissue. my country stipulates that the maximum allowable concentration of ozone in the atmosphere is 0.2 mg/m3. ——"Modern Hospital Disinfection" P94, Yang Huaming. Researcher at the Chinese People's Liberation Army Academy of Military Medical Sciences and Disinfection Expert
"When using ozone for air disinfection, in accordance with the requirements of the "Disinfection Technical Specifications", ozone Maintain a higher concentration. Of course, the disinfection effect is very good at such a high concentration, but personnel must leave the site at this time. ”
The Ozone Industry Association sets health standards: International Ozone Association: 0.1. ppm, exposure for 10 hours; United States: 0.1ppm, exposure for 8 hours; Germany, France, Japan and other countries: 0.1ppm, exposure for 10 hours; China: 0.15ppm, exposure for 8 hours.
"Literature reports show that when the ozone concentration is 0.02ppm, people with a sensitive sense of smell can detect it, which is called the sensory threshold value. When the concentration is 0.15ppm, it is the olfactory critical value. Most people can smell it, which is also hygienic. Standard point. When the concentration reaches 1-10ppm, it is called the irritation range, and when it is above 10ppm, it is the poisoning limit."
"The use of ozone in the room is not recommended internationally.
The country now has standards for outdoor ozone, with a maximum concentration of 200 micrograms/cubic meter, but indoor ozone standards have not yet been officially announced. If ozone cannot be controlled to a mild concentration for use in homes, it will have negative impacts. Some data show that the ozone concentration emitted by some ozone generators is 50-100 times that of household disinfection cabinets. Moreover, ordinary consumers do not have the ability to monitor. The harm caused by excessive ozone concentration has a certain process and cannot be seen in a short period of time. By the time there is a reaction, it may be too late. What should be pointed out now is that some businesses have seized on the fact that ordinary consumers do not understand this feature and exaggerated product functions in their advertisements, while brushing off the negative impacts of high concentrations of ozone. In the end, people spend money on environmental protection, but what they get is pollution. ” ——Professor Chen Chengzhang (former Dean of the School of Health, Sun Yat-sen Medical College)
Ozone can disinfect, but excessive ozone is an invisible killer!
▲ It strongly stimulates the human respiratory tract , causing sore throat, chest tightness and cough, bronchitis and emphysema;
▲ Ozone can cause human neurotoxicity, dizziness and headache, vision loss, and memory loss;
▲ Ozone will destroy vitamin E in human skin, causing wrinkles and dark spots on human skin;
▲ Ozone can also destroy the human body’s immune function, induce chromosomal lesions in lymphocytes, and accelerate aging. , causing pregnant women to give birth to deformed babies;
▲ The ozone and organic waste gas generated by the heat of the toner in the copy machine are strong carcinogens, which can cause various types of cancer and cardiovascular diseases.
Therefore, people must pay close attention to the harm caused by ozone and organic waste gas.
Our reporter investigated the ozone generators sold in Guangzhou stores and found that the products are mostly imported from abroad and the packaging labels are unclear; There are no identification words from relevant departments in the instructions; although some indicate "special precautions", if the user does not read them carefully, they are often easily ignored; some machine group offices are also equipped with a variety of domestically produced ozone and negative ion generators. etc. Users reported that due to poor quality, they broke down after a short period of use (Note: Experts point out that some negative ion generators also produce a large amount of ozone while generating negative ions, because the working principle is roughly the same, and the energy is absorbed by high-voltage discharge oxygen molecules. and release). ——"Pearl River Environmental News" Issue 295
"Ozone itself is a strong oxidant and has a disinfecting effect, but it needs to be in a closed state. High concentrations of ozone are a pollutant to humans, which can cause skin cancer and emphysema, reduce crop yields, and cause building materials to corrode due to oxidation. The current ozone concentration in Guangzhou is so high that some medical and health cleaning units use ozone for disinfection, which has increased the ozone content in the air. If household ozone generators are used in large quantities, it will inevitably aggravate man-made ozone pollution and increase the ozone concentration in urban areas, which is harmful to The environment poses a threat. As for emitting ozone into occupied rooms and closets, this is misleading. It is certain that ozone disinfection technology is very advanced internationally. The key is how to use it. We are currently conducting research on the rise of ozone in local areas and its causes. In the past, it was thought that it was mainly caused by the action of nitrogen oxides. Now it seems that it is mainly related to local (regional) volatile organic compounds. The concentrations of some compounds are not high, but It is very polluting. Ozone is too high in some areas, reducing crop yields by more than 10%. It is also harmful to vegetation and poses a threat to human health. ——Academician Fujia Mo (Guangzhou Institute of Geochemistry, Chinese Academy of Sciences)