What is the difference between G4 and F7 filters?

G4 and F7 are classifications of air filters based on their filtration efficiency and particle size capture capability. The main differences between G4 and F7 filters are as follows:

1. Filtration Efficiency:
G4 Filters: These are considered medium-efficiency filters. They typically capture larger particles, such as dust, pollen, and some mold spores. G4 filters have an efficiency rating of about 60-70% for particles larger than 10 microns.
F7 Filters: These are high-efficiency filters, often used in environments requiring better air quality. F7 filters can capture smaller particles, including fine dust and airborne pollutants, with an efficiency of 80-90% for particles in the 0.3 to 1 micron range.
2. Application:
G4 Filters: Generally used in pre-filtration systems, such as HVAC units, to remove larger contaminants before finer filtration stages. These filters are often employed in commercial buildings and homes where basic air quality is required.
F7 Filters: Commonly used in environments where higher air purity is essential, such as hospitals, laboratories, and offices. F7 filters are often utilized in combination with other filters in ventilation systems to ensure cleaner air.
3. Particle Size:
G4 Filters: Designed to capture coarse particles such as hair, fibers, and larger dust particles. Their focus is on removing visible debris.
F7 Filters: Target fine particles, including smoke, bacteria, and allergens, making them suitable for environments requiring high levels of air cleanliness.
4. Pressure Drop:
G4 Filters: These filters generally have a lower pressure drop, meaning they allow air to pass through more easily, resulting in lower energy consumption for fans.
F7 Filters: Due to their denser structure and higher filtration efficiency, F7 filters typically have a higher pressure drop, which can lead to increased energy consumption in the air system.