1. What are G3 and G4?
G3 and G4 belong to the primary filtration levels in the traditional European air filter classification system. It should be noted that with the development of air filtration standards, the ISO 16890 system is often used in current engineering projects to evaluate filter performance.
Therefore, when purchasing G3 or G4 filters, it is not recommended to only confirm "G3" or "G4". You should also further confirm the corresponding test standards, filtration efficiency, air volume, resistance and other parameters.
2. The main differences between G3 and G4
1. Different filtration efficiency
Generally speaking, G4 has a higher filtration capacity than G3 and can intercept more particles in the air.
G3 is mainly used for preliminary filtration of coarser particles, while G4 is usually used in pre-filtration scenarios that require slightly higher air cleanliness.
It should be noted that under different testing standards and testing methods, G3 and G4 cannot simply correspond to the actual particle filtration efficiency. Therefore, the actual testing data provided by the supplier should prevail when purchasing.
2. Different initial resistance
Under the same size and air volume conditions, G4 with higher filtration efficiency may usually have a relatively higher initial resistance.
However, the actual resistance is also related to the filter material, filter area, pleat structure and air volume, so the final resistance cannot be judged based only on the G3 or G4 grade.
3. Service life and dust holding capacity
The service life of the filter depends not only on the G3 or G4 grade, but also on the filter material area, air pollution level, air volume and operating time.
If there is a lot of dust in the air, you can choose a product with a larger filter area and higher dust holding capacity to reduce the frequency of filter replacement.
3. How to choose between G3 and G4?
What scenarios is G3 suitable for?
G3 can be used in scenarios with lower requirements for preliminary air filtration, such as:
General ventilation system;
Front-end pre-filtration of air conditioning system;
Primary filtration of fresh air system;
Preliminary interception of large particle dust.
If the system backend is also configured with G4, medium efficiency or HEPA filter, G3 can undertake the first stage of coarse filtering tasks.
What scenarios is G4 suitable for?
G4 is usually suitable for scenarios that require higher pre-filtering effects, such as:
Commercial building HVAC systems;
Industrial plant ventilation systems;
Clean room front-end pre-filtration;
Medical building air conditioning systems;
Food processing plant air handling systems;
HEPA filter front-end protection.
For systems with HEPA filters installed at the back end, proper configuration of G4 or other suitable pre-filters can reduce the load of particulate matter entering the high-efficiency filter.
4. Can G3 and G4 be directly interchanged?
We cannot simply assume that G4 can directly replace G3.
Although G4 usually has higher filtration capacity, you need to confirm when replacing the filter:
Whether the filter sizes are consistent;
Whether the rated air volume meets the requirements;
Whether the initial resistance is suitable for the fan;
Whether the installation frame matches;
Whether the system pressure difference is allowed;
Whether the back-end filter needs to be adjusted.
If the resistance of G4 is significantly higher than that of the original G3, and the residual pressure of the fan is insufficient, the system air volume may decrease.
Therefore, the filtration efficiency, air volume and resistance should be checked at the same time before replacing the filter.
5. What should you pay attention to when purchasing G3 and G4?
For projects and bulk purchases, it is not recommended to only write: G3 Air Filter / G4 Air Filter in the inquiry form
More reasonable purchase specifications should include:
Filter Class: G3 / G4;
Filter Dimensions;
Rated Airflow;
Initial Pressure Drop;
Filter Media;
Frame Material;
Dust Holding Capacity;
Test Standard;
Operating Conditions;
Packaging Requirements.
If the project adopts the ISO 16890 standard, the supplier should also be required to provide corresponding ISO 16890 performance data to avoid selection errors caused by simple comparisons between different standards.
6. Jiangsu Yueboyang primary-efficiency filter product supporting capabilities
Jiangsu Yueboyang Purification Equipment Co., Ltd. can provide G3, G4 and other primary-efficiency air filters, and can conduct product selection and customization according to the customer's filtration efficiency, design air volume, installation size, filter material and frame requirements.
The product can be used in front-end pre-filtration of HVAC systems, fresh air systems, industrial plants, food processing, medical buildings and clean rooms to provide front-end protection for medium-efficiency and HEPA high-efficiency filters.
7. Summary
Both G3 and G4 are primary filters. The core difference lies in filtration performance and applicable working conditions. Generally, the filtration capacity of G4 is higher than that of G3, but the actual selection should not only look at the filtration level, but also need to comprehensively consider the air volume, initial resistance, dust holding capacity, filter material, filtration area and back-end filtration equipment.
For general ventilation and coarse particle pre-filtration, G3 can be selected according to actual needs; for applications such as HVAC, clean rooms and HEPA front-end protection, G4 usually has wider applicability. The final selection should be based on the project design requirements and the supplier's actual testing data.
