PM2.5 refers to dust particulate matter with an aerodynamic equivalent diameter less than or equal to 2.5μm. This type of particulate matter can remain suspended in the air for a long time. If inhaled into the lungs, it will affect human health. The higher the content of PM2.5 in the air, the higher the concentration, and the more serious the air pollution.

Sources of PM2.5 Generation:

① Natural sources, including soil dust, plant pollen, spores, bacteria, etc.

② Anthropogenic sources, including coal combustion, gas combustion, fuel oil, automobile exhaust emissions, second-hand smoke, household dust, and other soot.

The regions with the highest fine particulate matter in the world are North Africa and the whole of North China, East China, and Central China. The World Health Organization (WHO) considers a PM2.5 value less than 10 to be safe, while these regions in China are all higher than 50 and close to 80, much higher than the Sahara Desert.

Hazards and impacts of PM2.5:

Although PM2.5 accounts for very little content in the atmosphere, it has a serious impact on air quality. Compared with larger atmospheric particles, PM2.5 has a smaller particle size, is rich in a large amount of toxic and harmful substances, stays in the atmosphere for a long time, and travels long distances, thus having a greater impact on human health and atmospheric environmental quality. Luftmy editor noticed that related studies show that the smaller the particles, the greater the harm to human health. Fine particles can float to far away places, so the impact range is large.

Fine particulate matter is more harmful to human health because the smaller the diameter, the deeper it enters the respiratory tract. Particles with a diameter of 10μm are usually deposited in the upper respiratory tract, while those below 2μm can penetrate deep into the bronchioles and alveoli, so PM2.5 is also known as "lung-penetrable particles." After PM2.5 enters the human body and reaches the alveoli, it directly affects the ventilation function of the lungs, making the body prone to a state of hypoxia.

On October 17, 2013, the International Agency for Research on Cancer under the World Health Organization released a report for the first time identifying air pollution as carcinogenic to humans and regarding it as a widespread and major environmental carcinogen. On November 12, 2013, the Chinese Academy of Social Sciences and the China Meteorological Administration jointly released the "Green Book on Climate Change." The report stated that haze weather affects health, and in addition to well-known consequences like worsening respiratory and heart system diseases, it also affects reproductive capacity.

With the improvement of people's living standards, the concern for air quality and requirements for air quality are also increasing. For example, more and more families choose to use air purifier equipment to purify PM2.5 and other dust particulate matter in indoor air. Detecting PM2.5 concentration data in air purifiers requires a PM2.5 sensor. The Luftmy laser PM2.5 dust sensor is a high-precision particulate matter concentration sensor based on Laser Mie scattering theory. The PM2.5 dust laser sensor LD11 can be embedded in various instruments or environmental improvement equipment related to the concentration of suspended particulate matter in the air, providing timely and accurate concentration data.