In the days when the fog is obscured by the sun, we all hope that a heavy rain will clean the sky, so that we can see the sunshine, the blue sky and white clouds, and we can breathe the fresh air deeply. The smell that makes us feel refreshed is ozone.
Ozone is an allotrope of oxygen composed of three oxygen atoms. Under normal temperature and pressure, it is a gas with a peculiar smell, and is very unstable and easily decomposed into oxygen, with a half-life of 20-30 minutes. In nature, ozone is mainly distributed in the stratosphere 15-50 kilometers away from the earth's surface. The ozone layer can absorb most of the sun's ultraviolet rays, protecting everything on the earth from ultraviolet rays.
Ozone has a very strong oxidizing property, which can quickly kill almost all kinds of bacteria, viruses, molds, fungi, protozoa, and oocysts in a short time. The disinfection efficiency is 300-600 times that of chlorine and 3000 times that of ultraviolet rays. For the odor in nature, the main components are ammonia, hydrogen sulfide, methyl mercaptan, dimethyl sulfide, dimethyl disulfide, etc. Ozone can decompose it into non-toxic and odorless substances. For organic volatiles, such as formaldehyde, benzene, etc., ozone also has a certain purification effect. Therefore, ozone is widely used in disinfection of water, air, and surface of objects, as well as environmental deodorization and odor removal.
But also because of the strong oxidizing properties of ozone, it can strongly stimulate the body's mucosal tissues, cause inflammation and even edema of the human respiratory system, and reduce human immunity, which can even be fatal. For some metal surfaces, it is also very corrosive. Therefore, many people talk about ozone discoloration, and even regard ozone as air pollution equivalent to PM2.5. Indeed, in the modern lifestyle, due to the increase in cars, car exhaust pollution produces a lot of ozone under the action of outdoor light; indoors, laser printers, electrostatic copiers, etc. all produce ozone. If ozone is continuously produced, the concentration of ozone in the air increases, that is to say, the amount of ozone produced per unit time is greater than or equal to the amount of decomposition of ozone, which will have a great impact on the air in the human settlement environment.
Usually the ozone concentration is safe below 0.1mg/m3. my country’s AQI requires that the ozone concentration is ≤0.16mg/m3. Under normal circumstances, if the concentration exceeds 0.043 mg/m3, we can smell it. If you can’t smell it, it is safe of. Because of the instability and smell of ozone, everyone will avoid it when smelling it, and ozone poisoning is rare.
Knowing these characteristics of ozone, we can reasonably use ozone to disinfect and remove formaldehyde and other odors. Generally, when ozone is used for disinfection and deodorization, the concentration is relatively high, and humans and animals have to leave. After two to thirty minutes, there is basically no residual ozone. If it is used for air purification in a human settlement environment, as long as the ozone concentration is lower than the national standard, it is safe. If you can't smell the ozone, then don't worry.
Why is there so much criticism in the media about ozone generator air purifiers? In fact, many commercial factors are involved. Businesses of different technology products are mutually exclusive, which magnifies the harm of ozone. In fact, the application of each technology will have its advantages and disadvantages, the key is how to use it rationally. There are many ways to purify air, and the way to achieve it is also different. The main reason is to look at the main pollutants in the ambient air and use appropriate methods for treatment.