As a Professional Air Purification Manufacturer, How to Recommend Air Filters Suitable for Customers? There Are Four Basic Points to Consider:
When recommending the appropriate efficiency of air filters, it's important to first identify the industry the customer operates in. If we recommend an air filter with efficiency that is too high, the customer might find that the air volume is insufficient, as not enough air will pass through the filter. Conversely, if we recommend a HEPA filter with efficiency below the industry standard, the result may be inadequate cleanliness, leading to failed acceptance tests and an unqualified status. Therefore, when recommending the efficiency of filters to customers, it's crucial to consider the following:
1. The Purification Level of Clean Rooms:
For clean rooms with purification levels of 300,000, 100,000, 10,000, and 1,000, it is recommended to adopt a three-stage filtration system: a pre-air filter (coarse air filter) rated G3-G4, a medium-efficiency air filter rated F6-F8, and a HEPA air filter rated H13. This setup is suitable for facilities such as pharmaceutical workshops, food workshops, cosmetics workshops, and photoelectric workshops. For dust-free workshops with a 1,000 or 100 clean level, a three- to four-stage filtration system is recommended, with the addition of a sub-high-efficiency filter. For these environments, an H14 efficiency HEPA air filter is recommended.
In hospitals, biological pharmaceutical facilities, disease control centers, and blood centers-where high air quality control is essential-four-stage filtration is recommended (pre-air filter, medium air filter, sub-HEPA filter, HEPA filter). These units require stringent pollution control. Since changing air filters can introduce environmental pollution, it is crucial to control pollution sources carefully. Adding a sub-efficiency HEPA filter, typically made of fiberglass with high dust-holding capacity, can protect the terminal HEPA filters and reduce the frequency of their replacement, thereby minimizing pollution risks.
2. Air Volume Demands:
Most dust-free workshops with electric exhaust units require very large air volumes, such as those in car coating, cosmetics shell coating, plastic shell coating, nameplate decoration, and glasses spraying industries. These industries need large air volumes, and the amount of air being supplied must be greater than the air output. Because the air supply system is equipped with at least three levels of filtration, there is at least three layers of resistance, while no resistance equipment is set at the air outlet window. The higher resistance of the three-stage air filter screens leads to a reduction in air supply volume, which can cause the workshop to become negatively pressurized, allowing dust to enter the cleanroom. Therefore, the HEPA filter efficiency in such workshops should not be too high, with H10-H12 sub-HEPA filters recommended to ensure the required air volume in the dust-free coating workshop.
3. Air Conditioning Systems in Four-Star Hotels, Airports, Senior Clubs, and Office Buildings:
For air conditioning systems (HVAC systems) in these environments, it is recommended to use primary and secondary filtration. This approach can reduce the frequency of air conditioning duct cleaning. The cost of cleaning the ducts equals five years' worth of changing all stages of air filters. Although adding a pre-filter and a medium-efficiency air filter (Medium and fine filters: M5-F9) may increase air conditioning load costs, it will save costs in the long term.
4. HEPA Filter Loading Recommendations:
We recommend users load HEPA filters at about 60% of the maximum rated air flow when configuring the terminal box (air handling unit/ceiling air flow box/air supply outlet unit). This practice can extend the service life of the air filter and reduce energy consumption. For example, a 48448422 high-efficiency air filter with a rated air flow of 1000 m³/h will improve to 99.999% efficiency when used at 600 m³/h, and its service life will be longer.
For instance, the maximum rated air flow for a 484484220 HEPA filter is 1000 m³/h. Under a 600 m³/h air volume, the resistance will be 60%, meaning that 220 Pa * 60% = 132 Pa. This is why AAF labels the initial resistance as 110 Pa on the 117057069 mini-pleated HEPA filter. Its maximum rated air flow reaches 1800 m³/h at a velocity of 0.45 m/s, and when under 1000 m³/h, the initial resistance must be 110 Pa. This setup is beneficial for users, so why not choose it?
F8-F9 sub-high efficiency V-type hepa air filter