The hepa filter efficiency is generally tested by the manufacturer, and the filter efficiency report sheet and certificate of compliance are attached when leaving the factory. For enterprises, hepa filter leakage test refers to on-site leakage test after the installation of hepa filters and their systems. It mainly checks for small pinholes and other damage in filter material, such as frame seals, gasket seals, and filter leakage in structure, etc.
The purpose of leakage test is to promptly discover defects in hepa filter itself and its installation by checking the sealing of the hepa filter and its connection with the installation frame, and take corresponding remedial measures to ensure the cleanliness of the clean area.
The purpose of hepa filter leakage test:
1. The material of the hepa air filter is not damaged;
2. Install properly.
Methods for leakage test in hepa filters:
Hepa filter leakage test basically involves placing challenge particles upstream of the hepa filter, and then using particle detection instruments on the surface and frame of the hepa filter to search for leakage. There are several different methods of leakage test, suitable for different situations.
Test methods include:
1. Aerosol photometer test method
2. Particle counter test method
3. Full efficiency test method
4. External air test method
Test instrument:
The instruments used are aerosol photometer and particle generator. The aerosol photometer has two display versions: analog and digital, which must be calibrated once a year. There are two types of particle generators, one is an ordinary particle generator, which only requires high-pressure air, and the other is a heated particle generator, which requires high-pressure air and power. The particle generator does not require calibration.
Precautions:
1. Any continuity reading exceeding 0.01% is considered as leakage. Each hepa air filter must not leak after testing and replacement, and the frame must not leak.
2. The repair area of each hepa air filter shall not be bigger than 3% of the area of the hepa air filter.
3. The length of any repair shall not exceed 38mm.
Post time: Dec-06-2023