We are in danger every day but Without consciousness

 Heating, ventilation, and air conditioning (HVAC) systems are currently a major focus of interest. This is because serious problems such as the so-called “sick building syndrome” can be directly attributed to poorly maintained and insanitary HVAC systems. Fine particles not only stay suspended longer in the air, they also are more easily trapped deep within the lungs.

Why we afraid PM2.5?

Particles less than 2.5 micrometers in diameter are called "fine" particles. These particles are so small they can be detected only with an electron microscope. Sources of fine particles include all types of combustion, including motor vehicles, power plants, residential wood burning, forest fires, agricultural burning, and some industrial processes.

Firstly, particulate enters the body through respiratory system, directly affecting the lungs.PM2.5 is harmful because it can be sucked into the lungs. What's more, small particles can even enter into blood and other organs directly. The person breathes about 10,000 liters of air a day, and when the air contains pollutants,  health is inevitably compromised.

Secondly, the type of harm is determined by what PM2.5 absorbs. What PM2.5 adsorbs determine what harm it does. If this area mainly adsorb heavy metals, it may produce more heavy metal poisoning in this area; If the adsorption is a carcinogen such as benzo and pyrene, cancer may be widespread ; If adsorption of PM2.5 in this region is mostly persistent organic pollutants, then it may harm for fertility. Different regions, the concentration of the same haze, or the concentration of pollutants, the harm to health is not same, may be the key is the composition. While current scientific studies have shown a correlation between haze and certain diseases, they have not revealed a definitive cause-and-effect relationship. Therefore, it is true that haze harms health, and scientists need to further study the causal relationship.

Meteorologists and medical experts believe that harm caused by haze is more than by sandstorms. Particles larger than 10 microns can be blocked out of a person's nose. Particles with particle sizes ranging from 2.5 to 10 microns can enter the upper respiratory tract, but some of them can be excreted through sputum. In addition, they also can be blocked by the villi inside the nasal cavity, causing relatively small harm to human health. Fine particles smaller than 2.5 micrometers, diameter is one-tenth of hair, are not easily blocked. When inhaled, they go directly into the bronchi, interfering with gas exchange in the lungs and causing illnesses including asthma, bronchitis and cardiovascular disease.

We inhale about 10,000 liters of air per day, and the dust that enters the alveoli can be absorbed quickly and directly into the blood circulation and distributed throughout the body without going through the liver for detoxification. At the same time, it impairs hemoglobin's ability to transport oxygen and loses blood. For patients with anemia and impaired circulation, this can have serious consequences. For example, it can worsen respiratory problems and even cause congestive heart failure and coronary artery disease.In short, these particles can also enter the blood through the bronchi and alveoli, in which the harmful gases, heavy metals and other dissolved in the blood, the greater harm to human health.The physiological structure of the human body determines that there is no filtering and blocking ability of PM2.5, while the harm of PM2.5 to human health has gradually exposed its horrible side with the progress of medical technology.

In the European Union, PM2.5 reduces life expectancy by 8.6 months. PM2.5 can also become a carrier of viruses and bacteria, contributing to the spread of respiratory infections. Currently, major developed countries in the world, as well as Japan, Thailand and India in Asia, have included PM2.5 in their air quality standards.

Srilan filter media for HVAC can solve this problem well.The efficiency which filter 0.3 microns can reach  more than 99%. HVAC has the function of filtering the polluted components in the indoor and outdoor air. The fresh air system will filter the outdoor air into the room, and meanwhile discharge the indoor dirty air out of the room. The whole process realizes air replacement, increases the concentration of oxygen in the room, and makes the indoor air fresh and clean.