Why does the fresh air system need to be equipped with a HEPA filter?

The role of fresh air system in air purification

With the acceleration of urbanization, air pollution has become increasingly serious, especially the threat of fine particles such as PM2.5 and PM10 to human health has become increasingly prominent. Especially in a closed indoor environment, the decline in air quality is more harmful to the human body. The emergence of the fresh air system solves this problem. By continuously introducing fresh air from the outside, it can reduce the indoor carbon dioxide concentration and reduce the accumulation of harmful substances in the air, thereby ensuring the health and comfort of the indoor environment.
Pollutants in the external air, such as dust, pollen, bacteria, smoke, etc., may also be introduced into the room with the fresh air system. These particles not only affect the indoor air quality, but may also cause allergic symptoms or respiratory diseases. In order to ensure that the introduced air is both fresh and harmless, it is crucial to equip it with an efficient HEPA filter. As a key air filtration component, the HEPA filter can effectively filter tiny particles in the air, thereby greatly improving the air purification effect of the fresh air system.

Air filtration mechanism of fresh air system

One of the core functions of fresh air system is to purify indoor air through air filtration. In order to efficiently remove various pollutants, fresh air system usually adopts multi-level filtration scheme, using different types of filter materials to work together to achieve efficient purification.
Multi-level filtration scheme: The air filtration mechanism of fresh air system usually includes multiple levels such as pre-filter, activated carbon filter, HEPA filter, etc. The pre-filter can remove larger particles, the activated carbon filter is responsible for adsorbing harmful gases and odors in the air, and the HEPA filter is specifically for filtering tiny particles (such as PM2.5, allergens, bacteria, etc.). Through multi-level combination, these filters can cooperate with each other to purify the air to the maximum extent.
Particle interception: The main function of HEPA filter is to intercept tiny particles in the air, especially dust, pollen, smoke and bacteria. The fiber gap of HEPA filter is extremely small, which can effectively capture most micron-level particles and ensure that pollutants in the air are filtered out to the greatest extent.
Balance between wind resistance and air circulation: While filtering efficiently, too high wind resistance will affect the air supply efficiency of the fresh air system, and thus affect the circulation of indoor air. When designing a fresh air system, the structure of the filter is usually optimized to maintain good air circulation while ensuring that the air purification effect is not compromised.

High-efficiency filtration principle of HEPA filter

HEPA filter (high-efficiency particulate air filter) is a high-efficiency filter material commonly used for air purification. Its working principle combines multiple physical mechanisms to effectively remove various tiny particles in the air.
Multiple interception mechanisms: HEPA filter mainly captures particles through diffusion, inertial collision, interception and electrostatic adsorption.
Diffusion: Smaller particles (such as fine aerosol particles) will collide with air molecules due to Brownian motion, change their trajectory, and thus be captured by the filter fibers.
Inertial collision: Large particles in fast-flowing air will not be able to follow the curved path of the airflow due to inertia, hit the filter fibers and be captured.
Interception: When particles come into contact with the filter fibers, the particles will be directly intercepted on the filter surface.
Electrostatic adsorption: Some fibers of the HEPA filter carry static charges and can adsorb charged particles in the air.
Microstructure: The fibers of the HEPA filter usually have a mesh structure with extremely fine gaps, which can capture micron-level and smaller particles. HEPA filters have a very high filtering effect on PM2.5 (particles with a diameter less than 2.5 microns) and other tiny pollutants.
Filter standard analysis: HEPA filters are divided into different levels according to their filtration efficiency, usually H10 to H14. Specifically:
H10 filter: can filter out about 85% of particles.
H13 filter: The filtration efficiency reaches 99.97%, which can filter out extremely fine particles.
H14 filter: The filtration efficiency can reach 99.995%, which is suitable for places with extremely high air quality requirements (such as hospitals, laboratories, etc.).

Core advantages of fresh air system equipped with HEPA filter

Fresh air system equipped with HEPA filter can provide many advantages that cannot be ignored:
Efficient removal of fine particles: HEPA filter can effectively remove tiny particles such as PM2.5 and PM1.0 to ensure fresh and healthy indoor air. The filtering effect on harmful substances such as allergens, bacteria, viruses, etc. makes it an ideal choice for homes, offices and public places.
Reducing airborne pollutants: Fine particles such as allergens and germs are easily transmitted through the air. HEPA filter can reduce the content of these substances in the air and reduce the risk of allergies and respiratory diseases.
Ensure long-term stable operation of equipment: Particles accumulate inside the fresh air system, which may cause equipment failure or reduced efficiency. The efficient filtering effect of HEPA filter can reduce these problems and extend the service life of the fresh air system.
Adapt to different scene requirements: According to different usage scenarios (such as home, office, medical institutions, etc.), HEPA filter can provide targeted air purification solutions to meet the needs of different users.

The value of HEPA filters in different application scenarios

The value of HEPA filters in different application scenarios is particularly prominent:
Family and residence: For people with children, the elderly or allergic constitutions, HEPA filters can effectively remove allergens, dust, pollen, etc. in the air, improve indoor air quality, and provide a healthier living environment.
Commercial and office buildings: In commercial office environments, HEPA filters can remove suspended particles and harmful substances in the air, improve the working comfort of office workers, improve air quality, and thus improve work efficiency.
Medical institutions and laboratories: In places with high cleanliness requirements such as hospitals, clinics or laboratories, HEPA filters can effectively remove pathogens and pollutants in the air, ensure a clean environment, and reduce the risk of cross-infection.
Industrial and special environments: In some production environments with high cleanliness requirements, such as electronics factories and pharmaceutical factories, HEPA filters can filter out tiny particles in the air to ensure the cleanliness of the production environment and avoid pollution sources.

How to choose a suitable HEPA filter for the fresh air system?

The following factors need to be considered when choosing a suitable HEPA filter for the fresh air system:
HEPA filter level: Different scenarios have different requirements for air quality, so it is necessary to choose a suitable HEPA filter level. For example, HEPA filters for home use can choose lower levels (such as H10), while medical institutions require high-efficiency H13 or H14 filters.
Balance between wind resistance and filtration efficiency: High-efficiency HEPA filters usually increase wind resistance, which will affect the air supply efficiency of the fresh air system. When choosing a suitable filter, ensure that air circulation is not affected too much while maintaining a high filtration efficiency.
Filter replacement and maintenance: HEPA filters need to be checked and replaced regularly. Generally speaking, they need to be replaced every 6 months to a year to ensure consistent filtration results. Cleaning and maintenance of the filter is also the key to maintaining long-term and efficient operation of the fresh air system.

The necessity of HEPA filters in fresh air systems

As an indispensable part of fresh air systems, HEPA filters provide users with clean and healthy air through their efficient particle filtration function. Whether in home, office, medical or industrial environments, HEPA filters can play an important role and meet the air purification needs of different scenarios. By properly selecting and maintaining HEPA filters, the long-term stable operation of the fresh air system can be ensured, the indoor air quality can be improved, and a fresher living and working environment can be created.