Hospital high-efficiency filter is a device used in hospital ventilation and air conditioning systems (HVAC) to efficiently filter pollutants such as small particles, bacteria, viruses, etc. in the air, providing a safer and cleaner air environment and ensuring the air quality of medical environments. The following provides a detailed introduction from the aspects of structural materials, working principles, performance parameters, application scenarios, and maintenance:
-* * Structural material**
-* * Filter material * *: Ultra fine glass fiber filter paper or polypropylene (PP) fiber filter paper are usually used, which have the characteristics of fine fiber diameter, large specific surface area, and high porosity, and can effectively intercept small particles.
-* * Framework * *: Generally made of metal (such as aluminum alloy, galvanized steel plate) or plastic, its function is to support the filter material, ensure the overall structural stability of the filter, and facilitate installation and fixation. -Sealing material: Used to prevent unfiltered air from leaking from the edge of the filter. Common sealing materials include rubber, polyurethane, etc. -Working principle: mainly based on various mechanisms such as screening, inertial collision, diffusion effect, electrostatic adsorption, etc. When dusty air passes through a high-efficiency filter, particles larger than the pore size of the filter paper are directly intercepted; Smaller particles, due to inertia, will deviate from the direction of the airflow and collide with the filter fibers, resulting in their capture; Smaller particles diffuse to the fiber surface and adhere through Brownian motion; Some filters also utilize electrostatic forces to enhance their ability to adsorb particles. -* * Performance parameters**
-* * Filtration efficiency * *: This is a key indicator for measuring the performance of high-efficiency filters, usually expressed as the filtration efficiency for specific particle sizes. For example, the filtration efficiency for particles with a particle size of ≥ 0.3 μ m reaches 99.97% or above (HEPA standard), and the filtration efficiency for particles with a particle size of ≥ 0.1 μ m reaches 99.995% or above (ULPA standard).
-Airflow: Refers to the volume of air passing through a filter per unit time, measured in cubic meters per hour (m ³/h). The air volume determines the amount of air that the filter can handle within a certain period of time, and should be selected according to actual usage scenarios and needs.
-Resistance: The pressure loss caused by air passing through a filter, measured in pascals (Pa). The magnitude of resistance affects the energy consumption and operational efficiency of the ventilation system. New high-efficiency filters generally have lower resistance, but as the usage time increases and dust accumulates, the resistance will gradually increase.
-Dust Capacity: The total amount of dust that a filter can hold, measured in grams (g). The dust holding capacity reflects the service life of the filter. When the dust holding capacity of the filter reaches a certain level, its filtration efficiency and resistance will undergo significant changes and need to be replaced. -* * Application scenarios**
-Operating Room: It is necessary to strictly control the concentration of bacteria and dust particles in the air to provide a sterile environment for surgery and reduce the risk of surgical infections.
-Intensive Care Unit (ICU): Patients have weakened immune systems and are susceptible to infections. Efficient filters can filter out bacteria in the air, protecting patients from external pollution. -Infectious Disease Ward: To prevent the spread of viruses, bacteria, and other pollutants in the ward to other areas of the hospital, avoid cross infection, and ensure clean air in the ward, which helps patients recover. -* * Laboratory * *: Various testing and research laboratories in hospitals have high requirements for environmental cleanliness. High efficiency filters can provide a stable and clean air environment for experiments, ensuring the accuracy of experimental results. -* * Maintenance and upkeep**
-* * Regular inspection * *: Regularly inspect the appearance of the filter to see if there is any damage, deformation, or other issues; Simultaneously monitor the resistance and filtration efficiency of the filter to determine if its performance has decreased.
-Cleaning and Replacement: Generally, high-efficiency filters do not need to be cleaned. When the resistance reaches about twice the initial resistance or the usage time reaches the specified period (usually 1-2 years), a new filter should be replaced in a timely manner.
-Pre filtration protection: Setting initial and intermediate filters at the front end of the high-efficiency filter to pre filter the air can effectively reduce the amount of dust entering the high-efficiency filter and extend its service life.
